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/*
 * Javassist, a Java-bytecode translator toolkit.
 * Copyright (C) 1999- Shigeru Chiba. All Rights Reserved.
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License.  Alternatively, the contents of this file may be used under
 * the terms of the GNU Lesser General Public License Version 2.1 or later,
 * or the Apache License Version 2.0.
 *
 * 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.
 */

package scouter.javassist;

import java.io.DataOutputStream;
import java.io.IOException;

import scouter.javassist.CannotCompileException;
import scouter.javassist.ClassPool;
import scouter.javassist.CtClass;
import scouter.javassist.CtConstructor;
import scouter.javassist.CtNewConstructor;
import scouter.javassist.Modifier;
import scouter.javassist.NotFoundException;
import scouter.javassist.bytecode.ClassFile;


class CtNewClass extends CtClassType {
    /* true if the class is an interface.
     */
    protected boolean hasConstructor;

    CtNewClass(String name, ClassPool cp,
               boolean isInterface, CtClass superclass) {
        super(name, cp);
        wasChanged = true;
        String superName;
        if (isInterface || superclass == null)
            superName = null;
        else
            superName = superclass.getName();

        classfile = new ClassFile(isInterface, name, superName);
        if (isInterface && superclass != null)
            classfile.setInterfaces(new String[] { superclass.getName() });

        setModifiers(Modifier.setPublic(getModifiers()));
        hasConstructor = isInterface;
    }

    protected void extendToString(StringBuffer buffer) {
        if (hasConstructor)
            buffer.append("hasConstructor ");

        super.extendToString(buffer);
    }

    public void addConstructor(CtConstructor c)
        throws CannotCompileException
    {
        hasConstructor = true;
        super.addConstructor(c);
    }

    public void toBytecode(DataOutputStream out)
        throws CannotCompileException, IOException
    {
        if (!hasConstructor)
            try {
                inheritAllConstructors();
                hasConstructor = true;
            }
            catch (NotFoundException e) {
                throw new CannotCompileException(e);
            }

        super.toBytecode(out);
    }

    /**
     * Adds constructors inhrited from the super class.
     *
     * After this method is called, the class inherits all the
     * constructors from the super class.  The added constructor
     * calls the super's constructor with the same signature.
     */
    public void inheritAllConstructors()
        throws CannotCompileException, NotFoundException
    {
        CtClass superclazz;
        CtConstructor[] cs;

        superclazz = getSuperclass();
        cs = superclazz.getDeclaredConstructors();

        int n = 0;
        for (int i = 0; i < cs.length; ++i) {
            CtConstructor c = cs[i];
            int mod = c.getModifiers();
            if (isInheritable(mod, superclazz)) {
                CtConstructor cons
                    = CtNewConstructor.make(c.getParameterTypes(),
                                            c.getExceptionTypes(), this);
                cons.setModifiers(mod & (Modifier.PUBLIC | Modifier.PROTECTED | Modifier.PRIVATE));
                addConstructor(cons);
                ++n;
            }
        }

        if (n < 1)
            throw new CannotCompileException(
                        "no inheritable constructor in " + superclazz.getName());

    }

    private boolean isInheritable(int mod, CtClass superclazz) {
        if (Modifier.isPrivate(mod))
            return false;

        if (Modifier.isPackage(mod)) {
            String pname = getPackageName();
            String pname2 = superclazz.getPackageName();
            if (pname == null)
                return pname2 == null;
            else
                return pname.equals(pname2);
        }

        return true;
    }
}