ByteCodeEnhancer.java

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package com.sun.jdo.api.persistence.enhancer;

import java.io.InputStream;
import java.io.OutputStream;

import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;


/**
 * A JDO enhancer, or byte-code enhancer, modifies the byte-codes of
 * Java class files to enable transparent loading and storing of the
 * fields of the persistent instances.
 */
public interface ByteCodeEnhancer
{
    /**
     * Enhances a given class according to the JDO meta-data. If the
     * input class has been enhanced or not - the output stream is
     * always written, either with the enhanced class or with the
     * non-enhanced class.
     *
     * @param inByteCode  The byte-code of the class to be enhanced.
     * @param outByteCode The byte-code of the enhanced class.
     *
     * @return  <code>true</code> if the class has been enhanced,
     *          <code>false</code> otherwise.
     */
   boolean enhanceClassFile(InputStream inByteCode,
                            OutputStream outByteCode)
        throws EnhancerUserException, EnhancerFatalError;


    /**
     * Enhances a given class according to the JDO meta-data. If the
     * input class has been enhanced or not - the output stream is
     * always written, either with the enhanced class or with the
     * non-enhanced class.
     * <br>
     * Furthermore the enhancer has to set the classname of
     * the enhanced class to the output stream wrapper object (it's
     * possible to get the input stream without knowing the classname).
     *
     * @param in  The byte-code of the class to be enhanced.
     * @param out The byte-code of the enhanced class.
     *
     * @return  <code>true</code> if the class has been enhanced,
     *          <code>false</code> otherwise.
     */
    boolean enhanceClassFile (InputStream         in,
                              OutputStreamWrapper out)
            throws EnhancerUserException,
                   EnhancerFatalError;

}