Apache BCEL Source Code Files are inside the Apache BCEL source package file like bcel-6.5.0-src.zip. Unzip the source package file and go to the "src/main" sub-directory, you will see source code files.

Here is the list of Java source code files of the Apache BCEL 6.5.0 in \Users\fyicenter\bcel-6.5.0\src:

⏎ org/apache/bcel/util/Repository.java

/*
 * 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.util;

import org.apache.bcel.classfile.JavaClass;

/**
 * Abstract definition of a class repository. Instances may be used to load classes from different sources and may be
 * used in the Repository.setRepository method.
 *
 * @see org.apache.bcel.Repository
 */
public interface Repository {

    /**
     * Stores the provided class under "clazz.getClassName()"
     */
    void storeClass(JavaClass clazz);

    /**
     * Removes class from repository
     */
    void removeClass(JavaClass clazz);

    /**
     * Finds the class with the name provided, if the class isn't there, return NULL.
     */
    JavaClass findClass(String className);

    /**
     * Finds the class with the name provided, if the class isn't there, make an attempt to load it.
     */
    JavaClass loadClass(String className) throws java.lang.ClassNotFoundException;

    /**
     * Finds the JavaClass instance for the given run-time class object
     */
    JavaClass loadClass(Class<?> clazz) throws java.lang.ClassNotFoundException;

    /**
     * Clears all entries from cache.
     */
    void clear();

    /**
     * Gets the ClassPath associated with this Repository
     */
    ClassPath getClassPath();
}

⏎ org/apache/bcel/util/Repository.java

Or download all of them as a single archive file:

File name: bcel-6.5.0-fyi.zip
File size: 706792 bytes
Release date: 2020-07-03
Download 

⇒ JDK "javap" Command

⇐ Install Apache BCEL 6.5.0 Binary Package

⇑ Apache BCEL (Byte Code Engineering Library)

⇑⇑ Java Bytecode Tools