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/optional/unix/Chgrp.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.
 *
 */

/*
 * Since the initial version of this file was developed on the clock on
 * an NSF grant I should say the following boilerplate:
 *
 * This material is based upon work supported by the National Science
 * Foundation under Grant No. EIA-0196404. Any opinions, findings, and
 * conclusions or recommendations expressed in this material are those
 * of the author and do not necessarily reflect the views of the
 * National Science Foundation.
 */

package org.apache.tools.ant.taskdefs.optional.unix;

import org.apache.tools.ant.BuildException;

/**
 * Chgrp equivalent for unix-like environments.
 *
 * @since Ant 1.6
 *
 * @ant.task category="filesystem"
 */
public class Chgrp extends AbstractAccessTask {

    private boolean haveGroup = false;

    /**
     * Chgrp task for setting unix group of a file.
     */
    public Chgrp() {
        super.setExecutable("chgrp");
    }

    /**
     * Set the group attribute.
     *
     * @param group    The new group for the file(s) or directory(ies)
     */
    public void setGroup(String group) {
        createArg().setValue(group);
        haveGroup = true;
    }

    /**
     * Ensure that all the required arguments and other conditions have
     * been set.
     */
    @Override
    protected void checkConfiguration() {
        if (!haveGroup) {
            throw new BuildException("Required attribute group not set in "
                                     + "chgrp", getLocation());
        }
        super.checkConfiguration();
    }

    /**
     * We don't want to expose the executable attribute, so override it.
     *
     * @param e User supplied executable that we won't accept.
     */
    @Override
    public void setExecutable(String e) {
        throw new BuildException(getTaskType()
                                 + " doesn't support the executable"
                                 + " attribute", getLocation());
    }
}

⏎ org/apache/tools/ant/taskdefs/optional/unix/Chgrp.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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