BEGIN LICENSE BLOCK *****
Version: EPL 2.0/GPL 2.0/LGPL 2.1
The contents of this file are subject to the Eclipse Public
License Version 2.0 (the "License"); you may not use this file
except in compliance with the License. You may obtain a copy of
the License at http://www.eclipse.org/legal/epl-v20.html
Software distributed under the License is distributed on an "AS
IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.
Copyright (C) 2002 Jan Arne Petersen 
Copyright (C) 2002-2004 Anders Bengtsson 
Copyright (C) 2004 Stefan Matthias Aust 
Copyright (C) 2004 David Corbin 
Copyright (C) 2004-2005 Thomas E Enebo 
Copyright (C) 2006 Kresten Krab Thorup 
Copyright (C) 2007 William N Dortch 
Alternatively, the contents of this file may be used under the terms of
either of the GNU General Public License Version 2 or later (the "GPL"),
or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
in which case the provisions of the GPL or the LGPL are applicable instead
of those above. If you wish to allow use of your version of this file only
under the terms of either the GPL or the LGPL, and not to allow others to
use your version of this file under the terms of the EPL, indicate your
decision by deleting the provisions above and replace them with the notice
and other provisions required by the GPL or the LGPL. If you do not delete
the provisions above, a recipient may use your version of this file under
the terms of any one of the EPL, the GPL or the LGPL.
END LICENSE BLOCK /***** BEGIN LICENSE BLOCK *****
 * Version: EPL 2.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * License Version 2.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.eclipse.org/legal/epl-v20.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Copyright (C) 2002 Jan Arne Petersen <jpetersen@uni-bonn.de>
 * Copyright (C) 2002-2004 Anders Bengtsson <ndrsbngtssn@yahoo.se>
 * Copyright (C) 2004 Stefan Matthias Aust <sma@3plus4.de>
 * Copyright (C) 2004 David Corbin <dcorbin@users.sourceforge.net>
 * Copyright (C) 2004-2005 Thomas E Enebo <enebo@acm.org>
 * Copyright (C) 2006 Kresten Krab Thorup <krab@gnu.org>
 * Copyright (C) 2007 William N Dortch <bill.dortch@gmail.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the EPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the EPL, the GPL or the LGPL.
 ***** END LICENSE BLOCK *****/

package org.jruby.javasupport;

import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Constructor;
import java.lang.reflect.Member;
import java.util.ArrayList;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Proxy;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

import com.headius.backport9.modules.Modules;
import org.jcodings.Encoding;

import org.jruby.*;
import org.jruby.javasupport.binding.Initializer;
import org.jruby.javasupport.proxy.JavaProxyClass;
import org.jruby.javasupport.proxy.JavaProxyConstructor;
import org.jruby.runtime.Arity;
import org.jruby.runtime.Block;
import org.jruby.runtime.Constants;
import org.jruby.runtime.Helpers;
import org.jruby.runtime.Visibility;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.runtime.load.Library;
import org.jruby.anno.JRubyMethod;
import org.jruby.anno.JRubyModule;
import org.jruby.exceptions.RaiseException;
import org.jruby.internal.runtime.methods.DynamicMethod;
import org.jruby.internal.runtime.methods.JavaMethod.JavaMethodN;
import org.jruby.internal.runtime.methods.JavaMethod.JavaMethodZero;
import org.jruby.java.addons.ArrayJavaAddons;
import org.jruby.java.addons.ClassJavaAddons;
import org.jruby.java.addons.IOJavaAddons;
import org.jruby.java.addons.KernelJavaAddons;
import org.jruby.java.addons.StringJavaAddons;
import org.jruby.java.codegen.RealClassGenerator;
import org.jruby.java.dispatch.CallableSelector;
import org.jruby.java.proxies.ArrayJavaProxy;
import org.jruby.java.proxies.ArrayJavaProxyCreator;
import org.jruby.java.proxies.ConcreteJavaProxy;
import org.jruby.java.proxies.MapJavaProxy;
import org.jruby.java.proxies.InterfaceJavaProxy;
import org.jruby.java.proxies.JavaInterfaceTemplate;
import org.jruby.java.proxies.JavaProxy;
import org.jruby.java.proxies.RubyObjectHolderProxy;
import org.jruby.java.util.SystemPropertiesMap;
import org.jruby.javasupport.proxy.JavaProxyClassFactory;
import org.jruby.util.*;
import org.jruby.util.cli.Options;
import org.jruby.util.collections.NonBlockingHashMapLong;

import static org.jruby.java.invokers.RubyToJavaInvoker.convertArguments;
import static org.jruby.runtime.Visibility.*;

@JRubyModule(name = "Java")
public class Java implements Library {
    public static final boolean NEW_STYLE_EXTENSION = Options.JI_NEWSTYLEEXTENSION.load();
    public static final boolean OBJECT_PROXY_CACHE = Options.JI_OBJECTPROXYCACHE.load();

    @Override
    public void load(Ruby runtime, boolean wrap) {
        final RubyModule Java = createJavaModule(runtime);

        JavaPackage.createJavaPackageClass(runtime, Java);

        org.jruby.javasupport.ext.Kernel.define(runtime);

        org.jruby.javasupport.ext.JavaLang.define(runtime);
        org.jruby.javasupport.ext.JavaLangReflect.define(runtime);
        org.jruby.javasupport.ext.JavaUtil.define(runtime);
        org.jruby.javasupport.ext.JavaUtilRegex.define(runtime);
        org.jruby.javasupport.ext.JavaIo.define(runtime);
        org.jruby.javasupport.ext.JavaNet.define(runtime);
        org.jruby.javasupport.ext.JavaMath.define(runtime);
        org.jruby.javasupport.ext.JavaTime.define(runtime);

        // load Ruby parts of the 'java' library
        runtime.getLoadService().load("jruby/java.rb", false);

        // rewire ArrayJavaProxy superclass to point at Object, so it inherits Object behaviors
        final RubyClass ArrayJavaProxy = runtime.getClass("ArrayJavaProxy");
        ArrayJavaProxy.setSuperClass(runtime.getJavaSupport().getObjectJavaClass().getProxyClass());
        ArrayJavaProxy.includeModule(runtime.getEnumerable());

        RubyClassPathVariable.createClassPathVariable(runtime);

        runtime.setJavaProxyClassFactory(JavaProxyClassFactory.createFactory());

        // modify ENV_JAVA to be a read/write version
        final Map systemProperties = new SystemPropertiesMap();
        RubyClass proxyClass = (RubyClass) getProxyClass(runtime, SystemPropertiesMap.class);
        runtime.getObject().setConstantQuiet("ENV_JAVA", new MapJavaProxy(runtime, proxyClass, systemProperties));
    }

    @SuppressWarnings("deprecation")
    public static RubyModule createJavaModule(final Ruby runtime) {
        final ThreadContext context = runtime.getCurrentContext();

        final RubyModule Java = runtime.defineModule("Java");

        Java.defineAnnotatedMethods(Java.class);

        final RubyClass _JavaObject = JavaObject.createJavaObjectClass(runtime, Java);
        JavaArray.createJavaArrayClass(runtime, Java, _JavaObject);
        JavaClass.createJavaClassClass(runtime, Java, _JavaObject);
        JavaMethod.createJavaMethodClass(runtime, Java);
        JavaConstructor.createJavaConstructorClass(runtime, Java);
        JavaField.createJavaFieldClass(runtime, Java);

        // set of utility methods for Java-based proxy objects
        JavaProxyMethods.createJavaProxyMethods(context);

        // the proxy (wrapper) type hierarchy
        JavaProxy.createJavaProxy(context);
        ArrayJavaProxyCreator.createArrayJavaProxyCreator(context);
        ConcreteJavaProxy.createConcreteJavaProxy(context);
        InterfaceJavaProxy.createInterfaceJavaProxy(context);
        ArrayJavaProxy.createArrayJavaProxy(context);

        // creates ruby's hash methods' proxy for Map interface
        MapJavaProxy.createMapJavaProxy(runtime);

        // also create the JavaProxy* classes
        JavaProxyClass.createJavaProxyClasses(runtime, Java);

        // The template for interface modules
        JavaInterfaceTemplate.createJavaInterfaceTemplateModule(context);

        runtime.defineModule("JavaUtilities").defineAnnotatedMethods(JavaUtilities.class);

        JavaArrayUtilities.createJavaArrayUtilitiesModule(runtime);

        // Now attach Java-related extras to core classes
        runtime.getArray().defineAnnotatedMethods(ArrayJavaAddons.class);
        runtime.getKernel().defineAnnotatedMethods(KernelJavaAddons.class);
        runtime.getString().defineAnnotatedMethods(StringJavaAddons.class);
        runtime.getIO().defineAnnotatedMethods(IOJavaAddons.class);
        runtime.getClassClass().defineAnnotatedMethods(ClassJavaAddons.class);

        if ( runtime.getObject().isConstantDefined("StringIO") ) {
            ((RubyClass) runtime.getObject().getConstant("StringIO")).defineAnnotatedMethods(IOJavaAddons.AnyIO.class);
        }

        // add all name-to-class mappings
        addNameClassMappings(runtime, runtime.getJavaSupport().getNameClassMap());

        // add some base Java classes everyone will need
        runtime.getJavaSupport().setObjectJavaClass( JavaClass.get(runtime, Object.class) );

        return Java;
    }

    public static class OldStyleExtensionInherited {
        @Deprecated
        public static IRubyObject inherited(IRubyObject self, IRubyObject subclass) {
            return inherited(self.getRuntime().getCurrentContext(), self, subclass);
        }

        @JRubyMethod
        public static IRubyObject inherited(ThreadContext context, IRubyObject self, IRubyObject subclass) {
            return invokeProxyClassInherited(context, self, subclass);
        }
    };

    public static class NewStyleExtensionInherited {
        @Deprecated
        public static IRubyObject inherited(IRubyObject self, IRubyObject subclass) {
            return inherited(self.getRuntime().getCurrentContext(), self, subclass);
        }

        @JRubyMethod
        public static IRubyObject inherited(ThreadContext context, IRubyObject self, IRubyObject subclass) {
            if ( ! ( subclass instanceof RubyClass ) ) {
                throw context.runtime.newTypeError(subclass, context.runtime.getClassClass());
            }
            JavaInterfaceTemplate.addRealImplClassNew((RubyClass) subclass);
            return context.nil;
        }
    };

    
This populates the master map from short-cut names to JavaClass instances for
a number of core Java types.
Params:
runtime – 
nameClassMap – /**
     * This populates the master map from short-cut names to JavaClass instances for
     * a number of core Java types.
     *
     * @param runtime
     * @param nameClassMap
     */
    private static void addNameClassMappings(final Ruby runtime, final Map<String, JavaClass> nameClassMap) {
        JavaClass booleanClass = JavaClass.get(runtime, Boolean.class);
        nameClassMap.put("boolean", JavaClass.get(runtime, Boolean.TYPE));
        nameClassMap.put("Boolean", booleanClass);
        nameClassMap.put("java.lang.Boolean", booleanClass);

        JavaClass byteClass = JavaClass.get(runtime, Byte.class);
        nameClassMap.put("byte", JavaClass.get(runtime, Byte.TYPE));
        nameClassMap.put("Byte", byteClass);
        nameClassMap.put("java.lang.Byte", byteClass);

        JavaClass shortClass = JavaClass.get(runtime, Short.class);
        nameClassMap.put("short", JavaClass.get(runtime, Short.TYPE));
        nameClassMap.put("Short", shortClass);
        nameClassMap.put("java.lang.Short", shortClass);

        JavaClass charClass = JavaClass.get(runtime, Character.class);
        nameClassMap.put("char", JavaClass.get(runtime, Character.TYPE));
        nameClassMap.put("Character", charClass);
        nameClassMap.put("Char", charClass);
        nameClassMap.put("java.lang.Character", charClass);

        JavaClass intClass = JavaClass.get(runtime, Integer.class);
        nameClassMap.put("int", JavaClass.get(runtime, Integer.TYPE));
        nameClassMap.put("Integer", intClass);
        nameClassMap.put("Int", intClass);
        nameClassMap.put("java.lang.Integer", intClass);

        JavaClass longClass = JavaClass.get(runtime, Long.class);
        nameClassMap.put("long", JavaClass.get(runtime, Long.TYPE));
        nameClassMap.put("Long", longClass);
        nameClassMap.put("java.lang.Long", longClass);

        JavaClass floatClass = JavaClass.get(runtime, Float.class);
        nameClassMap.put("float", JavaClass.get(runtime, Float.TYPE));
        nameClassMap.put("Float", floatClass);
        nameClassMap.put("java.lang.Float", floatClass);

        JavaClass doubleClass = JavaClass.get(runtime, Double.class);
        nameClassMap.put("double", JavaClass.get(runtime, Double.TYPE));
        nameClassMap.put("Double", doubleClass);
        nameClassMap.put("java.lang.Double", doubleClass);

        JavaClass bigintClass = JavaClass.get(runtime, BigInteger.class);
        nameClassMap.put("big_int", bigintClass);
        nameClassMap.put("big_integer", bigintClass);
        nameClassMap.put("BigInteger", bigintClass);
        nameClassMap.put("java.math.BigInteger", bigintClass);

        JavaClass bigdecimalClass = JavaClass.get(runtime, BigDecimal.class);
        nameClassMap.put("big_decimal", bigdecimalClass);
        nameClassMap.put("BigDecimal", bigdecimalClass);
        nameClassMap.put("java.math.BigDecimal", bigdecimalClass);

        JavaClass objectClass = JavaClass.get(runtime, Object.class);
        nameClassMap.put("object", objectClass);
        nameClassMap.put("Object", objectClass);
        nameClassMap.put("java.lang.Object", objectClass);

        JavaClass stringClass = JavaClass.get(runtime, String.class);
        nameClassMap.put("string", stringClass);
        nameClassMap.put("String", stringClass);
        nameClassMap.put("java.lang.String", stringClass);

        nameClassMap.put("void", JavaClass.get(runtime, Void.TYPE));
        nameClassMap.put("Void", JavaClass.get(runtime, Void.class));
    }

    public static IRubyObject create_proxy_class(
            IRubyObject self,
            IRubyObject name,
            IRubyObject javaClass,
            IRubyObject module) {
        final Ruby runtime = self.getRuntime();

        if ( ! ( module instanceof RubyModule ) ) {
            throw runtime.newTypeError(module, runtime.getModule());
        }

        final RubyModule proxyClass = get_proxy_class(self, javaClass);
        final String constName = name.asJavaString();
        IRubyObject existing = ((RubyModule) module).getConstantNoConstMissing(constName);

        if ( existing != null && existing != RubyBasicObject.UNDEF && existing != proxyClass ) {
            runtime.getWarnings().warn("replacing " + existing + " with " + proxyClass + " in constant '" + constName + " on class/module " + module);
        }

        ((RubyModule) module).setConstantQuiet(name.asJavaString(), proxyClass);
        return proxyClass;
    }

    public static IRubyObject get_java_class(final IRubyObject self, final IRubyObject name) {
        try {
            return JavaClass.for_name(self, name);
        }
        catch (Exception e) {
            self.getRuntime().getJavaSupport().handleNativeException(e, null);
            return self.getRuntime().getNil();
        }
    }

    
Same as Java#getInstance(runtime, rawJavaObject, false).
/**
     * Same as Java#getInstance(runtime, rawJavaObject, false).
     */
    public static IRubyObject getInstance(Ruby runtime, Object rawJavaObject) {
        return getInstance(runtime, rawJavaObject, false);
    }

    
Returns a new proxy instance of a type corresponding to rawJavaObject's class,
or the cached proxy if we've already seen this object.  Note that primitives
and strings are not coerced to corresponding Ruby types; use
JavaUtil.convertJavaToUsableRubyObject to get coerced types or proxies as
appropriate.
Params:
runtime – the JRuby runtime
rawJavaObject – the object to get a wrapper for
forceCache – whether to force the use of the proxy cache
See Also:
JavaUtil.convertJavaToUsableRubyObject
Returns:
the new (or cached) proxy for the specified Java object/**
     * Returns a new proxy instance of a type corresponding to rawJavaObject's class,
     * or the cached proxy if we've already seen this object.  Note that primitives
     * and strings are <em>not</em> coerced to corresponding Ruby types; use
     * JavaUtil.convertJavaToUsableRubyObject to get coerced types or proxies as
     * appropriate.
     *
     * @param runtime the JRuby runtime
     * @param rawJavaObject the object to get a wrapper for
     * @param forceCache whether to force the use of the proxy cache
     * @return the new (or cached) proxy for the specified Java object
     * @see JavaUtil#convertJavaToUsableRubyObject
     */
    public static IRubyObject getInstance(Ruby runtime, Object rawJavaObject, boolean forceCache) {
        if (rawJavaObject != null) {
            RubyClass proxyClass = (RubyClass) getProxyClass(runtime, rawJavaObject.getClass());

            if (OBJECT_PROXY_CACHE || forceCache || proxyClass.getCacheProxy()) {
                return runtime.getJavaSupport().getObjectProxyCache().getOrCreate(rawJavaObject, proxyClass);
            }
            return allocateProxy(rawJavaObject, proxyClass);
        }
        return runtime.getNil();
    }

    public static RubyModule getInterfaceModule(final Ruby runtime, final JavaClass javaClass) {
        return getInterfaceModule(runtime, javaClass.javaClass());
    }

    public static RubyModule getInterfaceModule(final Ruby runtime, final Class javaClass) {
        return Java.getProxyClass(runtime, javaClass);
    }

    public static RubyModule get_interface_module(final Ruby runtime, IRubyObject javaClassObject) {
        JavaClass javaClass; String javaName;
        if ( javaClassObject instanceof RubyString ) {
            javaClass = JavaClass.forNameVerbose(runtime, javaClassObject.asJavaString());
        }
        else if ( javaClassObject instanceof JavaClass ) {
            javaClass = (JavaClass) javaClassObject;
        }
        else if ( (javaName = unwrapJavaString(javaClassObject)) != null ) {
            javaClass = JavaClass.forNameVerbose(runtime, javaName);
        }
        else {
            throw runtime.newArgumentError("expected JavaClass, got " + javaClassObject);
        }
        return getInterfaceModule(runtime, javaClass);
    }

    public static RubyModule get_proxy_class(final IRubyObject self, final IRubyObject java_class) {
        final Ruby runtime = self.getRuntime();
        final JavaClass javaClass; String javaName;
        if ( java_class instanceof RubyString ) {
            javaClass = JavaClass.for_name(self, java_class);
        }
        else if ( java_class instanceof JavaClass ) {
            javaClass = (JavaClass) java_class;
        }
        else if ( (javaName = unwrapJavaString(java_class)) != null ) {
            javaClass = JavaClass.for_name(self, javaName);
        }
        else {
            throw runtime.newTypeError(java_class, runtime.getJavaSupport().getJavaClassClass());
        }
        return getProxyClass(runtime, javaClass);
    }

    private static String unwrapJavaString(IRubyObject arg) {
        if (arg instanceof JavaProxy) {
            Object str = ((JavaProxy) arg).getObject();
            return str instanceof String ? (String) str : null;
        }
        return null;
    }

    public static RubyClass getProxyClassForObject(Ruby runtime, Object object) {
        return (RubyClass) getProxyClass(runtime, object.getClass());
    }

    public static RubyModule getProxyClass(Ruby runtime, JavaClass javaClass) {
        return getProxyClass(runtime, javaClass.javaClass());
    }

    @SuppressWarnings("deprecation")
    public static RubyModule getProxyClass(final Ruby runtime, final Class<?> clazz) {
        RubyModule proxy = runtime.getJavaSupport().getUnfinishedProxy(clazz);
        if (proxy != null) return proxy;
        return runtime.getJavaSupport().getProxyClassFromCache(clazz);
    }

    @SuppressWarnings("deprecation")
    // Only used by proxy ClassValue calculator in JavaSupport
    static RubyModule createProxyClassForClass(final Ruby runtime, final Class<?> clazz) {
        final JavaSupport javaSupport = runtime.getJavaSupport();

        RubyModule proxy;
        RubyClass superClass = null;
        if (clazz.isInterface()) {
            proxy = (RubyModule) runtime.getJavaSupport().getJavaInterfaceTemplate().dup();
        } else {
            if (clazz.isArray()) {
                superClass = javaSupport.getArrayProxyClass();
            } else if (clazz.isPrimitive()) {
                superClass = javaSupport.getConcreteProxyClass();
                // NOTE: but the class methods such as 'new' will be removed (Initializer.setupProxyClass)
            } else if (clazz == Object.class) {
                superClass = javaSupport.getConcreteProxyClass();
            } else {
                // other java proxy classes added under their superclass' java proxy
                superClass = (RubyClass) getProxyClass(runtime, clazz.getSuperclass());
            }
            proxy = RubyClass.newClass(runtime, superClass);
        }

        // ensure proxy is visible down-thread
        javaSupport.beginProxy(clazz, proxy);
        try {
            if (clazz.isInterface()) {
                generateInterfaceProxy(runtime, clazz, proxy);
            } else {
                generateClassProxy(runtime, clazz, (RubyClass) proxy, superClass);
            }
        } finally {
            javaSupport.endProxy(clazz);
        }

        return proxy;
    }

    private static void generateInterfaceProxy(final Ruby runtime, final Class javaClass, final RubyModule proxy) {
        assert javaClass.isInterface();

        // include any interfaces we extend
        final Class<?>[] extended = javaClass.getInterfaces();
        for (int i = extended.length; --i >= 0; ) {
            RubyModule extModule = getInterfaceModule(runtime, extended[i]);
            proxy.includeModule(extModule);
        }
        Initializer.setupProxyModule(runtime, javaClass, proxy);
        addToJavaPackageModule(proxy);
    }

    private static void generateClassProxy(Ruby runtime, Class<?> clazz, RubyClass proxy, RubyClass superClass) {
        if ( clazz.isArray() ) {
            createProxyClass(runtime, proxy, clazz, superClass, true);

            if ( clazz.getComponentType() == byte.class ) {
                proxy.defineAnnotatedMethods( ByteArrayProxyMethods.class ); // to_s
            }
        }
        else if ( clazz.isPrimitive() ) {
            createProxyClass(runtime, proxy, clazz, superClass, true);
        }
        else if ( clazz == Object.class ) {
            // java.lang.Object is added at root of java proxy classes
            createProxyClass(runtime, proxy, clazz, superClass, true);
            if (NEW_STYLE_EXTENSION) {
                proxy.getMetaClass().defineAnnotatedMethods(NewStyleExtensionInherited.class);
            } else {
                proxy.getMetaClass().defineAnnotatedMethods(OldStyleExtensionInherited.class);
            }
            addToJavaPackageModule(proxy);
        }
        else {
            createProxyClass(runtime, proxy, clazz, superClass, false);
            // include interface modules into the proxy class
            final Class<?>[] interfaces = clazz.getInterfaces();
            for ( int i = interfaces.length; --i >= 0; ) {
                proxy.includeModule(getInterfaceModule(runtime, interfaces[i]));
            }
            if ( Modifier.isPublic(clazz.getModifiers()) ) {
                addToJavaPackageModule(proxy);
            }
        }

        // JRUBY-1000, fail early when attempting to subclass a final Java class;
        // solved here by adding an exception-throwing "inherited"
        if ( Modifier.isFinal(clazz.getModifiers()) ) {
            final String clazzName = clazz.getCanonicalName();
            proxy.getMetaClass().addMethod("inherited", new org.jruby.internal.runtime.methods.JavaMethod(proxy, PUBLIC, "inherited") {
                @Override
                public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name, IRubyObject[] args, Block block) {
                    throw context.runtime.newTypeError("can not extend final Java class: " + clazzName);
                }
            });
        }
    }

    private static RubyClass createProxyClass(final Ruby runtime,
        final RubyClass proxyClass, final Class<?> javaClass,
        final RubyClass superClass, boolean invokeInherited) {

        proxyClass.makeMetaClass( superClass.getMetaClass() );

        if ( Map.class.isAssignableFrom( javaClass ) ) {
            proxyClass.setAllocator( runtime.getJavaSupport().getMapJavaProxyClass().getAllocator() );
            proxyClass.defineAnnotatedMethods( MapJavaProxy.class );
            proxyClass.includeModule( runtime.getEnumerable() );
        }
        else {
            proxyClass.setAllocator( superClass.getAllocator() );
        }
        proxyClass.defineAnnotatedMethods( JavaProxy.ClassMethods.class );

        if ( invokeInherited ) proxyClass.inherit(superClass);

        Initializer.setupProxyClass(runtime, javaClass, proxyClass);

        return proxyClass;
    }

    public static class ByteArrayProxyMethods {

        @JRubyMethod
        public static IRubyObject to_s(ThreadContext context, IRubyObject self) {
            final Encoding ascii8bit = context.runtime.getEncodingService().getAscii8bitEncoding();

            // All bytes can be considered raw strings and forced to particular codings if not 8bitascii
            ByteList bytes = new ByteList((byte[]) ((ArrayJavaProxy) self).getObject(), ascii8bit);
            return RubyString.newStringLight(context.runtime, bytes);
        }

    }

    @Deprecated
    public static IRubyObject concrete_proxy_inherited(final IRubyObject clazz, final IRubyObject subclazz) {
        return invokeProxyClassInherited(clazz.getRuntime().getCurrentContext(), clazz, subclazz);
    }

    private static IRubyObject invokeProxyClassInherited(final ThreadContext context,
        final IRubyObject clazz, final IRubyObject subclazz) {
        final JavaSupport javaSupport = context.runtime.getJavaSupport();
        RubyClass javaProxyClass = javaSupport.getJavaProxyClass().getMetaClass();
        Helpers.invokeAs(context, javaProxyClass, clazz, "inherited", subclazz, Block.NULL_BLOCK);
        if ( ! ( subclazz instanceof RubyClass ) ) {
            throw context.runtime.newTypeError(subclazz, context.runtime.getClassClass());
        }
        setupJavaSubclass(context, (RubyClass) subclazz);
        return context.nil;
    }

    // called for Ruby sub-classes of a Java class
    private static void setupJavaSubclass(final ThreadContext context, final RubyClass subclass) {

        subclass.setInstanceVariable("@java_proxy_class", context.nil);

        // Subclasses of Java classes can safely use ivars, so we set this to silence warnings
        subclass.setCacheProxy(true);

        final RubyClass subclassSingleton = subclass.getSingletonClass();
        subclassSingleton.addReadWriteAttribute(context, "java_proxy_class");
        subclassSingleton.addMethod("java_interfaces", new JavaMethodZero(subclassSingleton, PUBLIC, "java_interfaces") {
            @Override
            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name) {
                IRubyObject javaInterfaces = self.getInstanceVariables().getInstanceVariable("@java_interfaces");
                if (javaInterfaces != null) return javaInterfaces.dup();
                return context.nil;
            }
        });

        subclass.addMethod("__jcreate!", new JCreateMethod(subclassSingleton));
    }

    public static class JCreateMethod extends JavaMethodN implements CallableSelector.CallableCache<JavaProxyConstructor> {

        private final NonBlockingHashMapLong<JavaProxyConstructor> cache = new NonBlockingHashMapLong<>(8);

        JCreateMethod(RubyModule cls) {
            super(cls, PUBLIC, "__jcreate!");
        }

        private static JavaProxyClass getProxyClass(final IRubyObject self) {
            final RubyClass metaClass = self.getMetaClass();
            IRubyObject proxyClass = metaClass.getInstanceVariable("@java_proxy_class");
            if (proxyClass == null || proxyClass.isNil()) { // lazy (proxy) class generation ... on JavaSubClass.new
                proxyClass = JavaProxyClass.getProxyClass(self.getRuntime(), metaClass);
                metaClass.setInstanceVariable("@java_proxy_class", proxyClass);
            }
            return (JavaProxyClass) proxyClass;
        }

        @Override
        public final IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name, Block block) {
            return call(context, self, clazz, name, IRubyObject.NULL_ARRAY);
        }

        @Override
        public final IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name, IRubyObject arg0, Block block) {
            final JavaProxyConstructor[] constructors = getProxyClass(self).getConstructors();

            final JavaProxyConstructor matching;
            switch (constructors.length) {
                case 1: matching = matchConstructor0ArityOne(context, constructors, arg0); break;
                default: matching = matchConstructorArityOne(context, constructors, arg0);
            }

            JavaObject newObject = matching.newInstance(self, arg0);
            return JavaUtilities.set_java_object(self, self, newObject);
        }

        @Override
        public final IRubyObject call(final ThreadContext context, IRubyObject self, RubyModule clazz, String name, IRubyObject[] args) {
            final int arity = args.length;
            final JavaProxyConstructor[] constructors = getProxyClass(self).getConstructors();

            final JavaProxyConstructor matching;
            switch (constructors.length) {
                case 1: matching = matchConstructor0(context, constructors, arity, args); break;
                default: matching = matchConstructor(context, constructors, arity, args);
            }

            JavaObject newObject = matching.newInstance(self, args);
            return JavaUtilities.set_java_object(self, self, newObject);
        }

        // assumes only 1 constructor exists!
        private JavaProxyConstructor matchConstructor0ArityOne(final ThreadContext context,
            final JavaProxyConstructor[] constructors, final IRubyObject arg0) {
            JavaProxyConstructor forArity = checkCallableForArity(1, constructors, 0);

            if ( forArity == null ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }

            final JavaProxyConstructor matching = CallableSelector.matchingCallableArityOne(
                context.runtime, this, new JavaProxyConstructor[] { forArity }, arg0
            );

            if ( matching == null ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }
            return matching;
        }

        // assumes only 1 constructor exists!
        private JavaProxyConstructor matchConstructor0(final ThreadContext context,
            final JavaProxyConstructor[] constructors, final int arity, final IRubyObject[] args) {
            JavaProxyConstructor forArity = checkCallableForArity(arity, constructors, 0);

            if ( forArity == null ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }

            final JavaProxyConstructor matching = CallableSelector.matchingCallableArityN(
                context.runtime, this, new JavaProxyConstructor[] { forArity }, args
            );

            if ( matching == null ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }
            return matching;
        }

        private JavaProxyConstructor matchConstructorArityOne(final ThreadContext context,
            final JavaProxyConstructor[] constructors, final IRubyObject arg0) {
            ArrayList<JavaProxyConstructor> forArity = findCallablesForArity(1, constructors);

            if ( forArity.size() == 0 ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }

            final JavaProxyConstructor matching = CallableSelector.matchingCallableArityOne(
                    context.runtime, this, forArity.toArray(new JavaProxyConstructor[forArity.size()]), arg0
            );

            if ( matching == null ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }
            return matching;
        }

        // generic (slowest) path
        private JavaProxyConstructor matchConstructor(final ThreadContext context,
            final JavaProxyConstructor[] constructors, final int arity, final IRubyObject... args) {
            ArrayList<JavaProxyConstructor> forArity = findCallablesForArity(arity, constructors);

            if ( forArity.size() == 0 ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }

            final JavaProxyConstructor matching = CallableSelector.matchingCallableArityN(
                context.runtime, this, forArity.toArray(new JavaProxyConstructor[forArity.size()]), args
            );

            if ( matching == null ) {
                throw context.runtime.newArgumentError("wrong number of arguments for constructor");
            }
            return matching;
        }

        public final JavaProxyConstructor getSignature(int signatureCode) {
            return cache.get(signatureCode);
        }

        public final void putSignature(int signatureCode, JavaProxyConstructor callable) {
            cache.put(signatureCode, callable);
        }
    }

    static <T extends ParameterTypes> ArrayList<T> findCallablesForArity(final int arity, final T[] callables) {
        final ArrayList<T> forArity = new ArrayList<>(callables.length);
        for ( int i = 0; i < callables.length; i++ ) {
            final T found = checkCallableForArity(arity, callables, i);
            if ( found != null ) forArity.add(found);
        }
        return forArity;
    }

    private static <T extends ParameterTypes> T checkCallableForArity(final int arity, final T[] callables, final int index) {
        final T callable = callables[index];
        final int callableArity = callable.getArity();

        if ( callableArity == arity ) return callable;
        // for arity 2 :
        // - callable arity 1 ([]...) is OK
        // - callable arity 2 (arg1, []...) is OK
        // - callable arity 3 (arg1, arg2, []...) is OK
        if ( callable.isVarArgs() && callableArity - 1 <= arity ) {
            return callable;
        }
        return null;
    }

    // package scheme 2: separate module for each full package name, constructed
    // from the camel-cased package segments: Java::JavaLang::Object,
    private static void addToJavaPackageModule(RubyModule proxyClass) {
        final Ruby runtime = proxyClass.getRuntime();
        final Class<?> clazz = (Class<?>)proxyClass.dataGetStruct();
        final String fullName;
        if ( ( fullName = clazz.getName() ) == null ) return;

        final RubyModule parentModule; final String className;

        if ( fullName.indexOf('$') != -1 ) {
            /*
             We don't want to define an inner class constant here, because it may conflict with static fields.
             Instead, we defer that constant definition to the declaring class's proxy initialization, which will deal
             with naming conflicts appropriately. See GH-6196.
             */
            return;
        }
        else {
            final int endPackage = fullName.lastIndexOf('.');
            String packageString = endPackage < 0 ? "" : fullName.substring(0, endPackage);
            parentModule = getJavaPackageModule(runtime, packageString);
            className = parentModule == null ? fullName : fullName.substring(endPackage + 1);
        }

        if ( parentModule != null && // TODO a Java Ruby class should not validate (as well)
            ( IdUtil.isConstant(className) || parentModule instanceof JavaPackage ) ) {
            if (parentModule.getConstantAt(className) == null) {
                parentModule.setConstant(className, proxyClass);
            }
        }
    }

    public static RubyModule getJavaPackageModule(final Ruby runtime, final Package pkg) {
        return getJavaPackageModule(runtime, pkg == null ? "" : pkg.getName());
    }

    public static RubyModule getJavaPackageModule(final Ruby runtime, final String packageString) {
        final String packageName; final int length;
        if ( ( length = packageString.length() ) == 0 ) {
            packageName = "Default";
        }
        else {
            StringBuilder name = new StringBuilder(length);
            for (int start = 0, offset; start < length; start = offset + 1) {
                offset = packageString.indexOf('.', start);
                if ( offset == -1 ) offset = length;
                name.append( Character.toUpperCase(packageString.charAt(start)) )
                    .append( packageString.substring(start + 1, offset) );
            }
            packageName = name.toString();
        }

        final RubyModule javaModule = runtime.getJavaSupport().getJavaModule();
        final IRubyObject packageModule = javaModule.getConstantAt(packageName);

        if ( packageModule == null ) {
            return createPackageModule(runtime, javaModule, packageName, packageString);
        }
        if ( packageModule instanceof RubyModule ) {
            return (RubyModule) packageModule;
        }
        return null;
    }

    private static RubyModule createPackageModule(final Ruby runtime,
        final RubyModule parentModule, final String name, final String packageString) {

        final RubyModule packageModule = JavaPackage.newPackage(runtime, packageString, parentModule);

        synchronized (parentModule) { // guard initializing in multiple threads
            final IRubyObject packageAlreadySet = parentModule.fetchConstant(name);
            if ( packageAlreadySet != null ) {
                return (RubyModule) packageAlreadySet;
            }
            parentModule.setConstant(name.intern(), packageModule);
            //MetaClass metaClass = (MetaClass) packageModule.getMetaClass();
            //metaClass.setAttached(packageModule);
        }
        return packageModule;
    }

    private static final Pattern CAMEL_CASE_PACKAGE_SPLITTER = Pattern.compile("([a-z0-9_]+)([A-Z])");

    private static RubyModule getPackageModule(final Ruby runtime, final String name) {
        final RubyModule javaModule = runtime.getJavaSupport().getJavaModule();
        final IRubyObject packageModule = javaModule.getConstantAt(name);
        if ( packageModule instanceof RubyModule ) return (RubyModule) packageModule;

        final String packageName;
        if ( "Default".equals(name) ) packageName = "";
        else {
            Matcher match = CAMEL_CASE_PACKAGE_SPLITTER.matcher(name);
            packageName = match.replaceAll("$1.$2").toLowerCase();
        }
        return createPackageModule(runtime, javaModule, name, packageName);
    }

    public static RubyModule get_package_module(final IRubyObject self, final IRubyObject name) {
        return getPackageModule(self.getRuntime(), name.asJavaString());
    }

    public static IRubyObject get_package_module_dot_format(final IRubyObject self,
        final IRubyObject dottedName) {
        final Ruby runtime = self.getRuntime();
        RubyModule module = getJavaPackageModule(runtime, dottedName.asJavaString());
        return module == null ? runtime.getNil() : module;
    }

    static RubyModule getProxyOrPackageUnderPackage(final ThreadContext context,
        final RubyModule parentPackage, final String name, final boolean cacheMethod) {
        final Ruby runtime = context.runtime;

        if ( name.length() == 0 ) {
            throw runtime.newArgumentError("empty class or package name");
        }

        final String fullName = JavaPackage.buildPackageName(parentPackage, name).toString();

        final RubyModule result;

        if ( ! Character.isUpperCase( name.charAt(0) ) ) {
            checkJavaReservedNames(runtime, name, false); // fails on primitives

            // this covers the rare case of lower-case class names (and thus will
            // fail 99.999% of the time). fortunately, we'll only do this once per
            // package name. (and seriously, folks, look into best practices...)
            RubyModule proxyClass = getProxyClassOrNull(runtime, fullName);
            if ( proxyClass != null ) result = proxyClass; /* else not primitive or l-c class */
            else {
                // Haven't found a class, continue on as though it were a package
                final RubyModule packageModule = getJavaPackageModule(runtime, fullName);
                // TODO: decompose getJavaPackageModule so we don't parse fullName
                if ( packageModule == null ) return null;
                result = packageModule;
            }
        }
        else {
            try { // First char is upper case, so assume it's a class name
                final RubyModule javaClass = getProxyClassOrNull(runtime, fullName);
                if ( javaClass != null ) result = javaClass;
                else {
                    if ( allowUppercasePackageNames(runtime) ) {
                        // for those not hip to conventions and best practices,
                        // we'll try as a package
                        result = getJavaPackageModule(runtime, fullName);
                        // NOTE result = getPackageModule(runtime, name);
                        if ( result == null ) {
                            throw runtime.newNameError("missing class (or package) name (`" + fullName + "')", fullName);
                        }
                    }
                    else {
                        throw runtime.newNameError("missing class name (`" + fullName + "')", fullName);
                    }
                }
            }
            catch (RuntimeException e) {
                if ( e instanceof RaiseException ) throw e;
                if (runtime.isDebug()) e.printStackTrace();
                throw runtime.newNameError("missing class or uppercase package name (`" + fullName + "'), caused by " + e.getMessage(), fullName);
            }
        }

        // saves class in singletonized parent, so we don't come back here :
        if ( cacheMethod ) bindJavaPackageOrClassMethod(parentPackage, name, result);

        return result;
    }

    private static boolean allowUppercasePackageNames(final Ruby runtime) {
        return runtime.getInstanceConfig().getAllowUppercasePackageNames();
    }

    private static void checkJavaReservedNames(final Ruby runtime, final String name,
        final boolean allowPrimitives) {
        // TODO: should check against all Java reserved names here, not just primitives
        if ( ! allowPrimitives && JavaClass.isPrimitiveName(name) ) {
            throw runtime.newArgumentError("illegal package name component: " + name);
        }
    }

    private static RubyModule getProxyClassOrNull(final Ruby runtime, final String className) {
        return getProxyClassOrNull(runtime, className, true);
    }

    private static RubyModule getProxyClassOrNull(final Ruby runtime, final String className,
        final boolean initJavaClass) {
        final Class<?> clazz;
        try { // loadJavaClass here to handle things like LinkageError through
            synchronized (Java.class) {
                // a circular load might potentially dead-lock when loading concurrently
                // this path is reached from JavaPackage#relativeJavaClassOrPackage ...
                // another part preventing concurrent proxy initialization dead-locks is :
                // JavaSupportImpl's proxyClassCache = ClassValue.newInstance( ... )
                // ... having synchronized RubyModule computeValue(Class<?>)
                clazz = runtime.getJavaSupport().loadJavaClass(className);
            }
        }
        catch (ExceptionInInitializerError ex) {
            throw runtime.newNameError("cannot initialize Java class " + className + ' ' + '(' + ex + ')', className, ex, false);
        }
        catch (UnsupportedClassVersionError ex) { // LinkageError
            String type = ex.getClass().getName();
            String msg = ex.getLocalizedMessage();
            if ( msg != null ) {
                final String unMajorMinorVersion = "unsupported major.minor version";
                // e.g. "com/sample/FooBar : Unsupported major.minor version 52.0"
                int idx = msg.indexOf(unMajorMinorVersion);
                if (idx > 0) {
                    idx += unMajorMinorVersion.length();
                    idx = mapMajorMinorClassVersionToJavaVersion(msg, idx);
                    if ( idx > 0 ) msg = "needs Java " + idx + " (" + type + ": " + msg + ')';
                    else msg = '(' + type + ": " + msg + ')';
                }
            }
            else msg = '(' + type + ')';
            // cannot link Java class com.sample.FooBar needs Java 8 (java.lang.UnsupportedClassVersionError: com/sample/FooBar : Unsupported major.minor version 52.0)
            throw runtime.newNameError("cannot link Java class " + className + ' ' + msg, className, ex, false);
        }
        catch (NoClassDefFoundError | ClassNotFoundException ncdfe) {
            // let caller try other names
            return null;
        }
        catch (LinkageError ex) {
            throw runtime.newNameError("cannot link Java class " + className + ' ' + '(' + ex + ')', className, ex, false);
        }
        catch (SecurityException ex) {
            throw runtime.newSecurityError(ex.getLocalizedMessage());
        }

        if ( initJavaClass ) {
            return getProxyClass(runtime, JavaClass.get(runtime, clazz));
        }
        return getProxyClass(runtime, clazz);
    }

    private static int mapMajorMinorClassVersionToJavaVersion(String msg, final int offset) {
        int end;
        if ( ( end = msg.indexOf('.', offset) ) == -1 ) end = msg.length();
        msg = msg.substring(offset, end).trim(); // handle " 52.0"
        try { // Java SE 6.0 = 50, Java SE 7 = 51, Java SE 8 = 52
            return Integer.parseInt(msg) - 50 + 6;
        }
        catch (RuntimeException ignore) { return 0; }
    }

    public static IRubyObject get_proxy_or_package_under_package(final ThreadContext context,
        final IRubyObject self, final IRubyObject parentPackage, final IRubyObject name) {
        final Ruby runtime = context.runtime;
        if ( ! ( parentPackage instanceof RubyModule ) ) {
            throw runtime.newTypeError(parentPackage, runtime.getModule());
        }
        final RubyModule result = getProxyOrPackageUnderPackage(context, (RubyModule) parentPackage, name.asJavaString(), true);
        return result != null ? result : context.nil;
    }

    private static RubyModule getTopLevelProxyOrPackage(final Ruby runtime,
        final String name, final boolean cacheMethod) {

        if ( name.length() == 0 ) {
            throw runtime.newArgumentError("empty class or package name");
        }

        final RubyModule result;

        if ( Character.isLowerCase( name.charAt(0) ) ) {
            // this covers primitives and (unlikely) lower-case class names
            RubyModule proxyClass = getProxyClassOrNull(runtime, name);
            if ( proxyClass != null ) result = proxyClass; /* else not primitive or l-c class */
            else {
                checkJavaReservedNames(runtime, name, true);

                final RubyModule packageModule = getJavaPackageModule(runtime, name);
                // TODO: decompose getJavaPackageModule so we don't parse fullName
                if ( packageModule == null ) return null;

                result = packageModule;
            }
        }
        else {
            RubyModule javaClass = getProxyClassOrNull(runtime, name);
            if ( javaClass != null ) result = javaClass;
            else {
                // upper-case package name
                // TODO: top-level upper-case package was supported in the previous (Ruby-based)
                // implementation, so leaving as is.  see note at #getProxyOrPackageUnderPackage
                // re: future approach below the top-level.
                result = getPackageModule(runtime, name);
            }
        }

        if ( cacheMethod ) bindJavaPackageOrClassMethod(runtime, name, result);

        return result;
    }

    private static boolean bindJavaPackageOrClassMethod(final Ruby runtime, final String name,
        final RubyModule packageOrClass) {
        final RubyModule javaPackage = runtime.getJavaSupport().getJavaModule();
        return bindJavaPackageOrClassMethod(javaPackage, name, packageOrClass);
    }

    private static boolean bindJavaPackageOrClassMethod(final RubyModule parentPackage,
        final String name, final RubyModule packageOrClass) {

        if ( parentPackage.getMetaClass().isMethodBound(name, false) ) {
            return false;
        }

        final RubyClass singleton = parentPackage.getSingletonClass();
        singleton.addMethod(name.intern(), new JavaAccessor(singleton, packageOrClass, parentPackage, name));
        return true;
    }

    private static class JavaAccessor extends org.jruby.internal.runtime.methods.JavaMethod {

        private final RubyModule packageOrClass;
        private final RubyModule parentPackage;

        JavaAccessor(final RubyClass singleton, final RubyModule packageOrClass, final RubyModule parentPackage, final String name) {
            super(singleton, PUBLIC, name);
            this.parentPackage = parentPackage; this.packageOrClass = packageOrClass;
        }

        @Override
        public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name, IRubyObject[] args, Block block) {
            if ( args.length != 0 ) {
                throw JavaPackage.packageMethodArgumentMismatch(context.runtime, parentPackage, name, args.length);
            }
            return call(context, self, clazz, name);
        }

        @Override
        public final IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name) {
            return this.packageOrClass;
        }

        @Override
        public final IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name, Block block) {
            return this.packageOrClass;
        }

        @Override
        public Arity getArity() { return Arity.noArguments(); }

    }

    static final class ProcToInterface extends org.jruby.internal.runtime.methods.DynamicMethod {

        ProcToInterface(final RubyClass singletonClass) {
            super(singletonClass, PUBLIC, "call");
        }

        @Override // method_missing impl :
        public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name, IRubyObject[] args, Block block) {
            final IRubyObject[] newArgs;
            switch( args.length ) {
                case 1 :  newArgs = IRubyObject.NULL_ARRAY; break;
                case 2 :  newArgs = new IRubyObject[] { args[1] }; break;
                case 3 :  newArgs = new IRubyObject[] { args[1], args[2] }; break;
                default : newArgs = new IRubyObject[ args.length - 1 ];
                    System.arraycopy(args, 1, newArgs, 0, newArgs.length);
            }
            return callProc(context, self, newArgs);
        }

        private static IRubyObject callProc(ThreadContext context, IRubyObject self, IRubyObject[] procArgs) {
            if ( ! ( self instanceof RubyProc ) ) {
                throw context.runtime.newTypeError("interface impl method_missing for block used with non-Proc object");
            }
            return ((RubyProc) self).call(context, procArgs);
        }

        @Override
        public DynamicMethod dup() {
            return this;
        }

        final ConcreteMethod getConcreteMethod(String name) { return new ConcreteMethod(name); }

        final class ConcreteMethod extends org.jruby.internal.runtime.methods.JavaMethod {

            ConcreteMethod(String name) {
                super(ProcToInterface.this.implementationClass, Visibility.PUBLIC, name);
            }

            @Override
            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule klazz, String name, Block block) {
                return ProcToInterface.this.callProc(context, self, IRubyObject.NULL_ARRAY);
            }

            @Override
            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule klazz, String name, IRubyObject arg0, Block block) {
                return ProcToInterface.this.callProc(context, self, new IRubyObject[]{arg0});
            }

            @Override
            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule klazz, String name, IRubyObject arg0, IRubyObject arg1, Block block) {
                return ProcToInterface.this.callProc(context, self, new IRubyObject[]{arg0, arg1});
            }

            @Override
            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule klazz, String name, IRubyObject arg0, IRubyObject arg1, IRubyObject arg2, Block block) {
                return ProcToInterface.this.callProc(context, self, new IRubyObject[]{arg0, arg1, arg2});
            }

            @Override
            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule klazz, String name, IRubyObject[] args, Block block) {
                return ProcToInterface.this.callProc(context, self, args);
            }

        }

    }

    private static RubyModule getProxyUnderClass(final ThreadContext context,
        final RubyModule enclosingClass, final String name) {
        final Ruby runtime = context.runtime;

        if ( name.length() == 0 ) throw runtime.newArgumentError("empty class name");

        Class<?> enclosing = JavaClass.getJavaClass(context, enclosingClass);

        if (enclosing == null) return null;

        final String fullName = enclosing.getName() + '$' + name;

        final RubyModule result = getProxyClassOrNull(runtime, fullName);
        //if ( result != null && cacheMethod ) bindJavaPackageOrClassMethod(enclosingClass, name, result);
        return result;
    }

    public static IRubyObject get_inner_class(final ThreadContext context,
        final RubyModule self, final IRubyObject name) { // const_missing delegate
        final String constName = name.asJavaString();

        final RubyModule innerClass = getProxyUnderClass(context, self, constName);
        if ( innerClass == null ) {
            return Helpers.invokeSuper(context, self, name, Block.NULL_BLOCK);
        }
        return cacheConstant(self, constName, innerClass, true); // hidden == true (private_constant)
    }

    @JRubyMethod(meta = true)
    public static IRubyObject const_missing(final ThreadContext context,
        final IRubyObject self, final IRubyObject name) {
        final Ruby runtime = context.runtime;
        final String constName = name.asJavaString();
        // it's fine to not add the "cached" method here - when users sticking to
        // constant access won't pay the "penalty" for adding dynamic methods ...
        final RubyModule packageOrClass = getTopLevelProxyOrPackage(runtime, constName, false);
        if ( packageOrClass == null ) return context.nil; // compatibility (with packages)
        return cacheConstant((RubyModule) self, constName, packageOrClass, false);
    }

    private static RubyModule cacheConstant(final RubyModule owner, // e.g. ::Java
        final String constName, final RubyModule packageOrClass, final boolean hidden) {
        if ( packageOrClass != null ) {
            // NOTE: if it's a package createPackageModule already set the constant
            // ... but in case it's a (top-level) Java class name we still need to:
            synchronized (owner) {
                final IRubyObject alreadySet = owner.fetchConstant(constName);
                if ( alreadySet != null ) return (RubyModule) alreadySet;
                owner.setConstant(constName, packageOrClass, hidden);
            }
            return packageOrClass;
        }
        return null;
    }

    @JRubyMethod(name = "method_missing", meta = true, required = 1)
    public static IRubyObject method_missing(ThreadContext context, final IRubyObject self,
        final IRubyObject name) { // JavaUtilities.get_top_level_proxy_or_package(name)
        // NOTE: getTopLevelProxyOrPackage will bind the (cached) method for us :
        final RubyModule result = getTopLevelProxyOrPackage(context.runtime, name.asJavaString(), true);
        if ( result != null ) return result;
        return context.nil;
    }

    @JRubyMethod(name = "method_missing", meta = true, rest = true)
    public static IRubyObject method_missing(ThreadContext context, final IRubyObject self,
        final IRubyObject[] args) {
        final IRubyObject name = args[0];
        if ( args.length > 1 ) {
            final int count = args.length - 1;
            throw context.runtime.newArgumentError("Java does not have a method `"+ name +"' with " + count + " arguments");
        }
        return method_missing(context, self, name);
    }

    public static IRubyObject get_top_level_proxy_or_package(final ThreadContext context,
        final IRubyObject self, final IRubyObject name) {
        final RubyModule result = getTopLevelProxyOrPackage(context.runtime, name.asJavaString(), true);
        return result != null ? result : context.nil;
    }

    public static IRubyObject wrap(Ruby runtime, IRubyObject java_object) {
        return getInstance(runtime, ((JavaObject) java_object).getValue());
    }

    
High-level object conversion utility function 'java_to_primitive' is the low-level version
/**
     * High-level object conversion utility function 'java_to_primitive' is the low-level version
     */
    @Deprecated
    @JRubyMethod(module = true, visibility = PRIVATE)
    public static IRubyObject java_to_ruby(IRubyObject recv, IRubyObject object, Block unusedBlock) {
        try {
            return JavaUtil.java_to_ruby(recv.getRuntime(), object);
        } catch (RuntimeException e) {
            recv.getRuntime().getJavaSupport().handleNativeException(e, null);
            // This point is only reached if there was an exception handler installed.
            return recv.getRuntime().getNil();
        }
    }

    
High-level object conversion utility.
/**
     * High-level object conversion utility.
     */
    @Deprecated
    @JRubyMethod(module = true, visibility = PRIVATE)
    public static IRubyObject ruby_to_java(final IRubyObject recv, IRubyObject object, Block unusedBlock) {
        return JavaUtil.ruby_to_java(recv, object, unusedBlock);
    }

    @Deprecated
    @JRubyMethod(module = true, visibility = PRIVATE)
    public static IRubyObject java_to_primitive(IRubyObject recv, IRubyObject object, Block unusedBlock) {
        return JavaUtil.java_to_primitive(recv, object, unusedBlock);
    }

    // TODO: Formalize conversion mechanisms between Java and Ruby
    @JRubyMethod(required = 2, module = true, visibility = PRIVATE)
    public static IRubyObject new_proxy_instance2(IRubyObject recv, final IRubyObject wrapper, IRubyObject ifcs, Block block) {
        IRubyObject[] javaClasses = ((RubyArray)ifcs).toJavaArray();

        // Create list of interface names to proxy (and make sure they really are interfaces)
        // Also build a hashcode from all classes to use for retrieving previously-created impl
        Class[] interfaces = new Class[javaClasses.length];
        for (int i = 0; i < javaClasses.length; i++) {
            if (!(javaClasses[i] instanceof JavaClass) || !((JavaClass) javaClasses[i]).interface_p().isTrue()) {
                throw recv.getRuntime().newArgumentError("Java interface expected. got: " + javaClasses[i]);
            }
            interfaces[i] = ((JavaClass) javaClasses[i]).javaClass();
        }

        return newInterfaceImpl(wrapper, interfaces);
    }

    public static JavaObject newInterfaceImpl(final IRubyObject wrapper, Class[] interfaces) {
        final Ruby runtime = wrapper.getRuntime();

        final int length = interfaces.length;
        switch ( length ) {
            case 1 :
                interfaces = new Class[] { interfaces[0], RubyObjectHolderProxy.class };
            case 2 :
                interfaces = new Class[] { interfaces[0], interfaces[1], RubyObjectHolderProxy.class };
            default :
                interfaces = ArraySupport.newCopy(interfaces, length + 1);
                interfaces[length] = RubyObjectHolderProxy.class;
        }

        final RubyClass wrapperClass = wrapper.getMetaClass();
        final boolean isProc = wrapperClass.isSingleton() && wrapperClass.getRealClass() == runtime.getProc();

        final JRubyClassLoader jrubyClassLoader = runtime.getJRubyClassLoader();

        if ( RubyInstanceConfig.INTERFACES_USE_PROXY ) {
            return JavaObject.wrap(runtime, newProxyInterfaceImpl(wrapper, interfaces, jrubyClassLoader));
        }

        final ClassDefiningClassLoader classLoader;
        // hashcode is a combination of the interfaces and the Ruby class we're using to implement them
        int interfacesHashCode = interfacesHashCode(interfaces);
        // if it's a singleton class and the real class is proc, we're doing closure conversion
        // so just use Proc's hashcode
        if ( isProc ) {
            interfacesHashCode = 31 * interfacesHashCode + runtime.getProc().hashCode();
            classLoader = jrubyClassLoader;
        }
        else { // normal new class implementing interfaces
            interfacesHashCode = 31 * interfacesHashCode + wrapperClass.getRealClass().hashCode();
            classLoader = new OneShotClassLoader(jrubyClassLoader);
        }
        final String implClassName = "org.jruby.gen.InterfaceImpl" + Math.abs(interfacesHashCode);
        Class<?> proxyImplClass;
        try {
            proxyImplClass = Class.forName(implClassName, true, jrubyClassLoader);
        }
        catch (ClassNotFoundException ex) {
            proxyImplClass = RealClassGenerator.createOldStyleImplClass(interfaces, wrapperClass, runtime, implClassName, classLoader);
        }

        try {
            Constructor<?> proxyConstructor = proxyImplClass.getConstructor(IRubyObject.class);
            return JavaObject.wrap(runtime, proxyConstructor.newInstance(wrapper));
        }
        catch (InvocationTargetException e) {
            throw mapGeneratedProxyException(runtime, e);
        }
        catch (ReflectiveOperationException e) {
            throw mapGeneratedProxyException(runtime, e);
        }
    }

    // NOTE: only used when java.lang.reflect.Proxy is to be used for interface impls (by default its not)
    private static Object newProxyInterfaceImpl(final IRubyObject wrapper, final Class[] interfaces, final ClassLoader loader) {
        return Proxy.newProxyInstance(loader, interfaces, new InterfaceProxyHandler(wrapper, interfaces));
    }

    private static final class InterfaceProxyHandler implements InvocationHandler {

        final IRubyObject wrapper;

        private final String[] ifaceNames; // interface names (sorted)

        InterfaceProxyHandler(final IRubyObject wrapper, final Class[] interfaces) {
            this.wrapper = wrapper;
            this.ifaceNames = new String[interfaces.length];
            for ( int i = 0; i < interfaces.length; i++ ) {
                ifaceNames[i] = interfaces[i].getName();
            }
            Arrays.sort(ifaceNames);
        }

        public Object invoke(Object proxy, Method method, Object[] nargs) throws Throwable {
            final String methodName = method.getName();
            final int length = nargs == null ? 0 : nargs.length;

            switch ( methodName ) {
                case "toString" :
                    if ( length == 0 && ! wrapper.respondsTo("toString") ) {
                        return proxyToString(proxy);
                    }
                    break;
                case "hashCode" :
                    if ( length == 0 && ! wrapper.respondsTo("hashCode") ) {
                        return proxyHashCode(proxy);
                    }
                    break;
                case "equals" :
                    if ( length == 1 && ! wrapper.respondsTo("equals") ) {
                        Class[] parameterTypes = getParameterTypes(method);
                        if ( parameterTypes[0] == Object.class ) return proxyEquals(proxy, nargs[0]);
                    }
                    break;
                case "__ruby_object" :
                    if ( length == 0 ) return wrapper;
                    break;
            }

            final Ruby runtime = wrapper.getRuntime();
            final ThreadContext context = runtime.getCurrentContext();

            //try {
                switch ( length ) {
                    case 0 :
                        return Helpers.invoke(context, wrapper, methodName).toJava(method.getReturnType());
                    case 1 :
                        IRubyObject arg = JavaUtil.convertJavaToUsableRubyObject(runtime, nargs[0]);
                        return Helpers.invoke(context, wrapper, methodName, arg).toJava(method.getReturnType());
                    default :
                        IRubyObject[] args = JavaUtil.convertJavaArrayToRuby(runtime, nargs);
                        return Helpers.invoke(context, wrapper, methodName, args).toJava(method.getReturnType());
                }
            //}
            //catch (RuntimeException e) {
            //    e.printStackTrace(); throw e;
            //}
        }

        final String proxyToString(final Object proxy) {
            // com.sun.proxy.$Proxy24{org.jruby.javasupport.Java$InterfaceProxyHandler@71ad51e9}
            return proxy.getClass().getName() + '{' + this + '}';
        }

        final boolean proxyEquals(final Object proxy, final Object otherProxy) {
            if ( proxy == otherProxy ) return true;
            if ( otherProxy == null ) return false;
            if ( Proxy.isProxyClass(otherProxy.getClass()) ) {
                InvocationHandler other = Proxy.getInvocationHandler(otherProxy);
                if ( other instanceof InterfaceProxyHandler ) {
                    InterfaceProxyHandler that = (InterfaceProxyHandler) other;
                    if ( this.wrapper != that.wrapper ) return false;
                    return Arrays.equals(this.ifaceNames, that.ifaceNames);
                }
            }
            return false;
        }

        final int proxyHashCode(final Object proxy) {
            int hash = 11 * this.wrapper.hashCode();
            for ( String iface : this.ifaceNames ) {
                hash = 31 * hash + iface.hashCode();
            }
            return hash;
        }

        private Map<Method, Class[]> parameterTypeCache;

        private Class[] getParameterTypes(final Method method) {
            Map<Method, Class[]> parameterTypeCache = this.parameterTypeCache;
            if (parameterTypeCache == null) {
                parameterTypeCache = new ConcurrentHashMap<Method, Class[]>(4);
                this.parameterTypeCache = parameterTypeCache;
            }

            Class[] parameterTypes = parameterTypeCache.get(method);
            if (parameterTypes == null) {
                parameterTypes = method.getParameterTypes();
                parameterTypeCache.put(method, parameterTypes);
            }
            return parameterTypes;
        }

    }

    @SuppressWarnings("unchecked")
    public static Class generateRealClass(final RubyClass clazz) {
        final Ruby runtime = clazz.getRuntime();
        final Class[] interfaces = getInterfacesFromRubyClass(clazz);

        // hashcode is a combination of the interfaces and the Ruby class we're using
        // to implement them
        int interfacesHashCode = interfacesHashCode(interfaces);
        // normal new class implementing interfaces
        interfacesHashCode = 31 * interfacesHashCode + clazz.hashCode();

        String implClassName = Constants.GENERATED_PACKAGE;
        if (clazz.getBaseName() == null) {
            // no-name class, generate a bogus name for it
            implClassName += "anon_class" + Math.abs(System.identityHashCode(clazz)) + '_' + Math.abs(interfacesHashCode);
        } else {
            implClassName += StringSupport.replaceAll(clazz.getName(), "::", "$$").toString() + '_' + Math.abs(interfacesHashCode);
        }
        Class<? extends IRubyObject> proxyImplClass;
        try {
            proxyImplClass = (Class<? extends IRubyObject>) Class.forName(implClassName, true, runtime.getJRubyClassLoader());
        }
        catch (ClassNotFoundException ex) {
            // try to use super's reified class; otherwise, RubyObject (for now)
            Class<? extends IRubyObject> superClass = clazz.getSuperClass().getRealClass().getReifiedClass();
            if ( superClass == null ) superClass = RubyObject.class;
            proxyImplClass = RealClassGenerator.createRealImplClass(superClass, interfaces, clazz, runtime, implClassName);

            // add a default initialize if one does not already exist and this is a Java-hierarchy class
            if ( NEW_STYLE_EXTENSION &&
                ! ( RubyBasicObject.class.isAssignableFrom(proxyImplClass) || clazz.getMethods().containsKey("initialize") ) ) {
                clazz.addMethod("initialize", new DummyInitialize(clazz));
            }
        }
        clazz.setReifiedClass(proxyImplClass);
        clazz.setRubyClassAllocator(proxyImplClass);

        return proxyImplClass;
    }

    private static final class DummyInitialize extends JavaMethodZero {

        DummyInitialize(final RubyClass clazz) { super(clazz, PRIVATE, "initialize"); }

        @Override
        public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name) {
            return context.nil;
        }

    }

    public static Constructor getRealClassConstructor(final Ruby runtime, Class<?> proxyImplClass) {
        try {
            return proxyImplClass.getConstructor(Ruby.class, RubyClass.class);
        }
        catch (NoSuchMethodException e) {
            throw mapGeneratedProxyException(runtime, e);
        }
    }

    public static IRubyObject constructProxy(Ruby runtime, Constructor proxyConstructor, RubyClass clazz) {
        try {
            return (IRubyObject) proxyConstructor.newInstance(runtime, clazz);
        }
        catch (InvocationTargetException e) {
            throw mapGeneratedProxyException(runtime, e);
        }
        catch (ReflectiveOperationException e) {
            throw mapGeneratedProxyException(runtime, e);
        }
    }

    private static RaiseException mapGeneratedProxyException(final Ruby runtime, final ReflectiveOperationException e) {
        RaiseException ex = runtime.newTypeError("Exception instantiating generated interface impl:\n" + e);
        ex.initCause(e);
        return ex;
    }

    private static RaiseException mapGeneratedProxyException(final Ruby runtime, final InvocationTargetException e) {
        RaiseException ex = runtime.newTypeError("Exception instantiating generated interface impl:\n" + e.getTargetException());
        ex.initCause(e);
        return ex;
    }

    public static IRubyObject allocateProxy(Object javaObject, RubyClass clazz) {
        final Ruby runtime = clazz.getRuntime();
        // Arrays are never stored in OPC
        if ( clazz.getSuperClass() == runtime.getJavaSupport().getArrayProxyClass() ) {
            return new ArrayJavaProxy(runtime, clazz, javaObject, JavaUtil.getJavaConverter(javaObject.getClass().getComponentType()));
        }

        final IRubyObject proxy = clazz.allocate();
        if ( proxy instanceof JavaProxy ) {
            ((JavaProxy) proxy).setObject(javaObject);
        }
        else {
            JavaObject wrappedObject = JavaObject.wrap(runtime, javaObject);
            proxy.dataWrapStruct(wrappedObject);
        }
        return proxy;
    }

    public static IRubyObject wrapJavaObject(Ruby runtime, Object object) {
        return allocateProxy(object, getProxyClassForObject(runtime, object));
    }

    @SuppressWarnings("unchecked")
    public static Class[] getInterfacesFromRubyClass(RubyClass klass) {
        Set<Class> interfaces = new HashSet<Class>();
        // walk all superclasses aggregating interfaces
        while (klass != null) {
            IRubyObject maybeInterfaces = klass.getInstanceVariables().getInstanceVariable("@java_interfaces");
            if (maybeInterfaces instanceof RubyArray) {
                final RubyArray moreInterfaces = (RubyArray) maybeInterfaces;
                if ( ! moreInterfaces.isFrozen() ) moreInterfaces.setFrozen(true);
                interfaces.addAll(moreInterfaces);
            }
            klass = klass.getSuperClass();
        }

        return interfaces.toArray(new Class[interfaces.size()]);
    }

    private static int interfacesHashCode(Class[] a) {
        if (a == null) {
            return 0;
        }

        int result = 1;

        for (Class element : a)
            result = 31 * result + (element == null ? 0 : element.hashCode());

        return result;
    }

    
Params:
iface – 
Returns:
the sole un-implemented method for a functional-style interface or null
@note
This method is internal and might be subject to change, do not assume its part of JRuby's API!/**
     * @param iface
     * @return the sole un-implemented method for a functional-style interface or null
     * @note This method is internal and might be subject to change, do not assume its part of JRuby's API!
     */
    public static Method getFunctionalInterfaceMethod(final Class<?> iface) {
        assert iface.isInterface();
        Method single = null;
        for ( final Method method : iface.getMethods() ) {
            final int mod = method.getModifiers();
            if ( Modifier.isStatic(mod) ) continue;
            if ( Modifier.isAbstract(mod) ) {
                try { // check if it's equals, hashCode etc. :
                    Object.class.getMethod(method.getName(), method.getParameterTypes());
                    continue; // abstract but implemented by java.lang.Object
                }
                catch (NoSuchMethodException e) { /* fall-through */ }
                catch (SecurityException e) {
                    // NOTE: we could try check for FunctionalInterface on Java 8
                }
            }
            else continue; // not-abstract ... default method
            if ( single == null ) single = method;
            else return null; // not a functional iface
        }
        return single;
    }

    
Try to set the given member to be accessible, considering open modules and avoiding the actual setAccessible
call when it would produce a JPMS warning. All classes on Java 8 are considered open, allowing setAccessible
to proceed.
The open check is based on this class, Java.java, which will be in whatever core or dist JRuby module you are
using.
/**
     * Try to set the given member to be accessible, considering open modules and avoiding the actual setAccessible
     * call when it would produce a JPMS warning. All classes on Java 8 are considered open, allowing setAccessible
     * to proceed.
     *
     * The open check is based on this class, Java.java, which will be in whatever core or dist JRuby module you are
     * using.
     */
    public static <T extends AccessibleObject & Member> boolean trySetAccessible(T member) {
        return Modules.trySetAccessible(member, Java.class);
    }

}