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/UnsupportedElementException.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;

/**
 * Used to report attempts to set an unsupported element
 * When the attempt to set the element is made,
 * the code does not not know the name of the task/type
 * based on a mapping from the classname to the task/type.
 * However one class may be used by a lot of task/types.
 * This exception may be caught by code that does know
 * the task/type and it will reset the message to the
 * correct message.
 * This will be done once (in the case of a recursive
 * call to handlechildren).
 *
 * @since Ant 1.6.3
 */
public class UnsupportedElementException extends BuildException {
    private static final long serialVersionUID = 1L;

    private final String element;

    /**
     * Constructs an unsupported element exception.
     * @param msg The string containing the message.
     * @param element The name of the incorrect element.
     */
    public UnsupportedElementException(String msg, String element) {
        super(msg);
        this.element = element;
    }

    /**
     * Get the element that is wrong.
     *
     * @return the element name.
     */
    public String getElement() {
        return element;
    }
}

⏎ org/apache/tools/ant/UnsupportedElementException.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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