Apache Ant Source Code Files are inside the Apache Ant source package file like apache-ant-1.10.10-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 Ant 1.10.10 in \Users\fyicenter\apache-ant-1.10.10\src\main:

⏎ org/apache/tools/ant/taskdefs/BZip2.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
 *
 *      https://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.tools.ant.taskdefs;


import java.io.BufferedOutputStream;
import java.io.IOException;
import java.nio.file.Files;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.util.FileUtils;
import org.apache.tools.bzip2.CBZip2OutputStream;

/**
 * Compresses a file with the BZIP2 algorithm. Normally used to compress
 * non-compressed archives such as TAR files.
 *
 * @since Ant 1.5
 *
 * @ant.task category="packaging"
 */

public class BZip2 extends Pack {
    /**
     * Compress the zipFile.
     */
    protected void pack() {
        CBZip2OutputStream zOut = null;
        try {
            BufferedOutputStream bos =
                new BufferedOutputStream(Files.newOutputStream(zipFile.toPath()));
            bos.write('B');
            bos.write('Z');
            zOut = new CBZip2OutputStream(bos);
            zipResource(getSrcResource(), zOut);
        } catch (IOException ioe) {
            String msg = "Problem creating bzip2 " + ioe.getMessage();
            throw new BuildException(msg, ioe, getLocation());
        } finally {
            FileUtils.close(zOut);
        }
    }

    /**
     * Whether this task can deal with non-file resources.
     *
     * <p>This implementation returns true only if this task is
     * &lt;bzip2&gt;.  Any subclass of this class that also wants to
     * support non-file resources needs to override this method.  We
     * need to do so for backwards compatibility reasons since we
     * can't expect subclasses to support resources.</p>
     * @return true if this task support non file resources.
     * @since Ant 1.7
     */
    protected boolean supportsNonFileResources() {
        return getClass().equals(BZip2.class);
    }
}

⏎ org/apache/tools/ant/taskdefs/BZip2.java

Or download all of them as a single archive file:

File name: apache-ant-1.10.10-fyi.zip
File size: 2392938 bytes
Release date: 2021-04-17
Download 

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