ClassfileLoader.java

/*
 *  Copyright (c) 2001-2024, Jean Tessier
 *  All rights reserved.
 *  
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *  
 *      * Redistributions of source code must retain the above copyright
 *        notice, this list of conditions and the following disclaimer.
 *  
 *      * 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.
 *  
 *      * Neither the name of Jean Tessier nor the names of his 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 REGENTS 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 com.jeantessier.classreader;

import java.io.*;
import java.util.*;

/**
 *  Base interface for parsing <code>.class</code> files.
 *  This should have been a Java interface, but I needed
 *  the protected contract for the Decorator Pattern.
 *
 *  @see ClassfileLoaderDecorator
 */
public abstract class ClassfileLoader {
    // Main methods
    public abstract Classfile getClassfile(String name);
    public abstract Collection<Classfile> getAllClassfiles();
    public abstract Collection<String> getAllClassNames();

    public void load(Collection<String> filenames) {
        fireBeginSession();

        filenames.forEach(this::load);

        fireEndSession();
    }

    // Protected contract for Decorator Pattern
    protected abstract void load(String filename);
    protected abstract void load(String filename, InputStream in);
    protected abstract Classfile load(DataInput in) throws IOException;

    // Event stuff
    public abstract void addLoadListener(LoadListener listener);
    public abstract void removeLoadListener(LoadListener listener);
    protected abstract void fireBeginSession();
    protected abstract void fireBeginGroup(String group_name, int size);
    protected abstract void fireBeginClassfile(String filename);
    protected abstract void fireBeginFile(String filename);
    protected abstract void fireEndClassfile(String filename, Classfile classfile);
    protected abstract void fireEndFile(String filename);
    protected abstract void fireEndGroup(String group_name);
    protected abstract void fireEndSession();
}