ASM: a very small and fast Java bytecode manipulation framework
Copyright (c) 2000-2011 INRIA, France Telecom
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. Neither the name of the copyright holders nor the names of its
   contributors may be used to endorse or promote products derived from
   this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
THE POSSIBILITY OF SUCH DAMAGE.
/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.objectweb.asm.optimizer;

import java.util.HashMap;

import org.objectweb.asm.Handle;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;

A constant pool.
Author:
Eric Bruneton/**
 * A constant pool.
 * 
 * @author Eric Bruneton
 */
public class ConstantPool extends HashMap<Constant, Constant> {

    private final Constant key1 = new Constant();

    private final Constant key2 = new Constant();

    private final Constant key3 = new Constant();

    private final Constant key4 = new Constant();

    private final Constant key5 = new Constant();

    public Constant newInteger(final int value) {
        key1.set(value);
        Constant result = get(key1);
        if (result == null) {
            result = new Constant(key1);
            put(result);
        }
        return result;
    }

    public Constant newFloat(final float value) {
        key1.set(value);
        Constant result = get(key1);
        if (result == null) {
            result = new Constant(key1);
            put(result);
        }
        return result;
    }

    public Constant newLong(final long value) {
        key1.set(value);
        Constant result = get(key1);
        if (result == null) {
            result = new Constant(key1);
            put(result);
        }
        return result;
    }

    public Constant newDouble(final double value) {
        key1.set(value);
        Constant result = get(key1);
        if (result == null) {
            result = new Constant(key1);
            put(result);
        }
        return result;
    }

    public Constant newUTF8(final String value) {
        key1.set('s', value, null, null);
        Constant result = get(key1);
        if (result == null) {
            result = new Constant(key1);
            put(result);
        }
        return result;
    }

    private Constant newString(final String value) {
        key2.set('S', value, null, null);
        Constant result = get(key2);
        if (result == null) {
            newUTF8(value);
            result = new Constant(key2);
            put(result);
        }
        return result;
    }

    public Constant newClass(final String value) {
        key2.set('C', value, null, null);
        Constant result = get(key2);
        if (result == null) {
            newUTF8(value);
            result = new Constant(key2);
            put(result);
        }
        return result;
    }

    public Constant newMethodType(final String methodDescriptor) {
        key2.set('t', methodDescriptor, null, null);
        Constant result = get(key2);
        if (result == null) {
            newUTF8(methodDescriptor);
            result = new Constant(key2);
            put(result);
        }
        return result;
    }

    public Constant newHandle(final int tag, final String owner,
            final String name, final String desc) {
        key4.set((char) ('h' - 1 + tag), owner, name, desc);
        Constant result = get(key4);
        if (result == null) {
            if (tag <= Opcodes.H_PUTSTATIC) {
                newField(owner, name, desc);
            } else {
                newMethod(owner, name, desc, tag == Opcodes.H_INVOKEINTERFACE);
            }
            result = new Constant(key4);
            put(result);
        }
        return result;
    }

    public Constant newConst(final Object cst) {
        if (cst instanceof Integer) {
            int val = ((Integer) cst).intValue();
            return newInteger(val);
        } else if (cst instanceof Float) {
            float val = ((Float) cst).floatValue();
            return newFloat(val);
        } else if (cst instanceof Long) {
            long val = ((Long) cst).longValue();
            return newLong(val);
        } else if (cst instanceof Double) {
            double val = ((Double) cst).doubleValue();
            return newDouble(val);
        } else if (cst instanceof String) {
            return newString((String) cst);
        } else if (cst instanceof Type) {
            Type t = (Type) cst;
            int s = t.getSort();
            if (s == Type.OBJECT) {
                return newClass(t.getInternalName());
            } else if (s == Type.METHOD) {
                return newMethodType(t.getDescriptor());
            } else { // s == primitive type or array
                return newClass(t.getDescriptor());
            }
        } else if (cst instanceof Handle) {
            Handle h = (Handle) cst;
            return newHandle(h.getTag(), h.getOwner(), h.getName(), h.getDesc());
        } else {
            throw new IllegalArgumentException("value " + cst);
        }
    }

    public Constant newField(final String owner, final String name,
            final String desc) {
        key3.set('G', owner, name, desc);
        Constant result = get(key3);
        if (result == null) {
            newClass(owner);
            newNameType(name, desc);
            result = new Constant(key3);
            put(result);
        }
        return result;
    }

    public Constant newMethod(final String owner, final String name,
            final String desc, final boolean itf) {
        key3.set(itf ? 'N' : 'M', owner, name, desc);
        Constant result = get(key3);
        if (result == null) {
            newClass(owner);
            newNameType(name, desc);
            result = new Constant(key3);
            put(result);
        }
        return result;
    }

    public Constant newInvokeDynamic(String name, String desc, Handle bsm,
            Object... bsmArgs) {
        key5.set(name, desc, bsm, bsmArgs);
        Constant result = get(key5);
        if (result == null) {
            newNameType(name, desc);
            newHandle(bsm.getTag(), bsm.getOwner(), bsm.getName(),
                    bsm.getDesc());
            for (int i = 0; i < bsmArgs.length; i++) {
                newConst(bsmArgs[i]);
            }
            result = new Constant(key5);
            put(result);
        }
        return result;
    }

    public Constant newNameType(final String name, final String desc) {
        key2.set('T', name, desc, null);
        Constant result = get(key2);
        if (result == null) {
            newUTF8(name);
            newUTF8(desc);
            result = new Constant(key2);
            put(result);
        }
        return result;
    }

    private Constant get(final Constant key) {
        return get((Object) key);
    }

    private void put(final Constant cst) {
        put(cst, cst);
    }
}