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/input/MultipleChoiceInputRequest.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.input;

import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Vector;

/**
 * Encapsulates an input request.
 *
 * @since Ant 1.5
 */
public class MultipleChoiceInputRequest extends InputRequest {
    private final LinkedHashSet<String> choices;

    /**
     * @param prompt The prompt to show to the user.  Must not be null.
     * @param choices holds all input values that are allowed.
     *                Must not be null.
     * @deprecated Use {@link #MultipleChoiceInputRequest(String,Collection)} instead
     */
    @Deprecated
    public MultipleChoiceInputRequest(String prompt, Vector<String> choices) {
        this(prompt, (Collection<String>) choices);
    }

    /**
     * @param prompt The prompt to show to the user.  Must not be null.
     * @param choices holds all input values that are allowed.
     *                Must not be null.
     */
    public MultipleChoiceInputRequest(String prompt, Collection<String> choices) {
        super(prompt);
        if (choices == null) {
            throw new IllegalArgumentException("choices must not be null");
        }
        this.choices = new LinkedHashSet<>(choices);
    }

    /**
     * @return The possible values.
     */
    public Vector<String> getChoices() {
        return new Vector<>(choices);
    }

    /**
     * @return true if the input is one of the allowed values.
     */
    @Override
    public boolean isInputValid() {
        return choices.contains(getInput())
            || (getInput().isEmpty() && getDefaultValue() != null);
    }
}

⏎ org/apache/tools/ant/input/MultipleChoiceInputRequest.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
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