/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache 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.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */
package org.apache.bcel.verifier.statics;


import org.apache.bcel.classfile.AnnotationDefault;
import org.apache.bcel.classfile.AnnotationEntry;
import org.apache.bcel.classfile.Annotations;
import org.apache.bcel.classfile.BootstrapMethods;
import org.apache.bcel.classfile.Code;
import org.apache.bcel.classfile.CodeException;
import org.apache.bcel.classfile.ConstantClass;
import org.apache.bcel.classfile.ConstantDouble;
import org.apache.bcel.classfile.ConstantFieldref;
import org.apache.bcel.classfile.ConstantFloat;
import org.apache.bcel.classfile.ConstantInteger;
import org.apache.bcel.classfile.ConstantInterfaceMethodref;
import org.apache.bcel.classfile.ConstantInvokeDynamic;
import org.apache.bcel.classfile.ConstantLong;
import org.apache.bcel.classfile.ConstantMethodHandle;
import org.apache.bcel.classfile.ConstantMethodType;
import org.apache.bcel.classfile.ConstantMethodref;
import org.apache.bcel.classfile.ConstantNameAndType;
import org.apache.bcel.classfile.ConstantPool;
import org.apache.bcel.classfile.ConstantString;
import org.apache.bcel.classfile.ConstantUtf8;
import org.apache.bcel.classfile.ConstantValue;
import org.apache.bcel.classfile.Deprecated;
import org.apache.bcel.classfile.EnclosingMethod;
import org.apache.bcel.classfile.ExceptionTable;
import org.apache.bcel.classfile.Field;
import org.apache.bcel.classfile.InnerClass;
import org.apache.bcel.classfile.InnerClasses;
import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.classfile.LineNumber;
import org.apache.bcel.classfile.LineNumberTable;
import org.apache.bcel.classfile.LocalVariable;
import org.apache.bcel.classfile.LocalVariableTable;
import org.apache.bcel.classfile.LocalVariableTypeTable;
import org.apache.bcel.classfile.Method;
import org.apache.bcel.classfile.MethodParameters;
import org.apache.bcel.classfile.NestMembers;
import org.apache.bcel.classfile.Node;
import org.apache.bcel.classfile.ParameterAnnotationEntry;
import org.apache.bcel.classfile.ParameterAnnotations;
import org.apache.bcel.classfile.Signature;
import org.apache.bcel.classfile.SourceFile;
import org.apache.bcel.classfile.StackMap;
import org.apache.bcel.classfile.StackMapEntry;
import org.apache.bcel.classfile.Synthetic;
import org.apache.bcel.classfile.Unknown;
import org.apache.bcel.verifier.exc.AssertionViolatedException;

BCEL's Node classes (those from the classfile API that accept() Visitor
instances) have toString() methods that were not designed to be robust,
this gap is closed by this class.
When performing class file verification, it may be useful to output which
entity (e.g. a Code instance) is not satisfying the verifier's
constraints, but in this case it could be possible for the toString()
method to throw a RuntimeException.
A (new StringRepresentation(Node n)).toString() never throws any exception.
Note that this class also serves as a placeholder for more sophisticated message
handling in future versions of JustIce.
/**
 * BCEL's Node classes (those from the classfile API that <B>accept()</B> Visitor
 * instances) have <B>toString()</B> methods that were not designed to be robust,
 * this gap is closed by this class.
 * When performing class file verification, it may be useful to output which
 * entity (e.g. a <B>Code</B> instance) is not satisfying the verifier's
 * constraints, but in this case it could be possible for the <B>toString()</B>
 * method to throw a RuntimeException.
 * A (new StringRepresentation(Node n)).toString() never throws any exception.
 * Note that this class also serves as a placeholder for more sophisticated message
 * handling in future versions of JustIce.
 *
 */
public class StringRepresentation extends org.apache.bcel.classfile.EmptyVisitor {
    
The string representation, created by a visitXXX() method, output by toString(). /** The string representation, created by a visitXXX() method, output by toString(). */
    private String tostring;
    
The node we ask for its string representation. Not really needed; only for debug output. /** The node we ask for its string representation. Not really needed; only for debug output. */
    private final Node n;

    
Creates a new StringRepresentation object which is the representation of n.
Params:
n – The node to represent.
See Also:
toString()/**
     * Creates a new StringRepresentation object which is the representation of n.
     *
     * @param n The node to represent.
     * @see #toString()
     */
    public StringRepresentation(final Node n) {
        this.n = n;
        n.accept(this); // assign a string representation to field 'tostring' if we know n's class.
    }

    
Returns the String representation.
/**
     * Returns the String representation.
     */
    @Override
    public String toString() {
// The run-time check below is needed because we don't want to omit inheritance
// of "EmptyVisitor" and provide a thousand empty methods.
// However, in terms of performance this would be a better idea.
// If some new "Node" is defined in BCEL (such as some concrete "Attribute"), we
// want to know that this class has also to be adapted.
        if (tostring == null) {
            throw new AssertionViolatedException(
                "Please adapt '" + getClass() + "' to deal with objects of class '" + n.getClass() + "'.");
        }
        return tostring;
    }

    
Returns the String representation of the Node object obj;
this is obj.toString() if it does not throw any RuntimeException,
or else it is a string derived only from obj's class name.
/**
     * Returns the String representation of the Node object obj;
     * this is obj.toString() if it does not throw any RuntimeException,
     * or else it is a string derived only from obj's class name.
     */
    private String toString(final Node obj) {
        String ret;
        try {
            ret = obj.toString();
        }

        catch (final RuntimeException e) {
            // including ClassFormatException, trying to convert the "signature" of a ReturnaddressType LocalVariable
            // (shouldn't occur, but people do crazy things)
            String s = obj.getClass().getName();
            s = s.substring(s.lastIndexOf(".") + 1);
            ret = "<<" + s + ">>";
        }
        return ret;
    }

    ////////////////////////////////
    // Visitor methods start here //
    ////////////////////////////////
    // We don't of course need to call some default implementation:
    // e.g. we could also simply output "Code" instead of a possibly
    // lengthy Code attribute's toString().
    @Override
    public void visitCode(final Code obj) {
        //tostring = toString(obj);
        tostring = "<CODE>"; // We don't need real code outputs.
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitAnnotation(final Annotations obj)
    {
        //this is invoked whenever an annotation is found
        //when verifier is passed over a class
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitLocalVariableTypeTable(final LocalVariableTypeTable obj)
    {
        //this is invoked whenever a local variable type is found
        //when verifier is passed over a class
        tostring = toString(obj);
    }

    @Override
    public void visitCodeException(final CodeException obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantClass(final ConstantClass obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantDouble(final ConstantDouble obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantFieldref(final ConstantFieldref obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantFloat(final ConstantFloat obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantInteger(final ConstantInteger obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantInterfaceMethodref(final ConstantInterfaceMethodref obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantLong(final ConstantLong obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantMethodref(final ConstantMethodref obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantNameAndType(final ConstantNameAndType obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantPool(final ConstantPool obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantString(final ConstantString obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantUtf8(final ConstantUtf8 obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitConstantValue(final ConstantValue obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitDeprecated(final Deprecated obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitExceptionTable(final ExceptionTable obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitField(final Field obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitInnerClass(final InnerClass obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitInnerClasses(final InnerClasses obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitJavaClass(final JavaClass obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitLineNumber(final LineNumber obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitLineNumberTable(final LineNumberTable obj) {
        tostring = "<LineNumberTable: " + toString(obj) + ">";
    }

    @Override
    public void visitLocalVariable(final LocalVariable obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitLocalVariableTable(final LocalVariableTable obj) {
        tostring = "<LocalVariableTable: " + toString(obj) + ">";
    }

    @Override
    public void visitMethod(final Method obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitSignature(final Signature obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitSourceFile(final SourceFile obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitStackMap(final StackMap obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitSynthetic(final Synthetic obj) {
        tostring = toString(obj);
    }

    @Override
    public void visitUnknown(final Unknown obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitEnclosingMethod(final EnclosingMethod obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitBootstrapMethods(final BootstrapMethods obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitMethodParameters(final MethodParameters obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitConstantInvokeDynamic(final ConstantInvokeDynamic obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitStackMapEntry(final StackMapEntry obj) {
        tostring = toString(obj);
    }
    
Since:
6.0/**
     * @since 6.0
     */

    @Override
    public void visitParameterAnnotation(final ParameterAnnotations obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitAnnotationEntry(final AnnotationEntry obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitAnnotationDefault(final AnnotationDefault obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitConstantMethodType(final ConstantMethodType obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitConstantMethodHandle(final ConstantMethodHandle obj) {
        tostring = toString(obj);
    }

    
Since:
6.0/**
     * @since 6.0
     */
    @Override
    public void visitParameterAnnotationEntry(final ParameterAnnotationEntry obj) {
        tostring = toString(obj);
    }

    
Since:
6.4.0/**
     * @since 6.4.0
     */
    @Override
    public void visitNestMembers(final NestMembers obj) {
        tostring = toString(obj);
    }
}