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Ant example source code file (

This example Ant source code file ( is included in the "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Ant tags/keywords

buildexception, buildexception, commandline, commandline, defaultcompileradapter, failed, file, io, ioexception, javacexternal, javacexternal, string, using, v, v

The source code

 *  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
 *  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.




 * Performs a compile using javac externally.
 * @since Ant 1.4
public class JavacExternal extends DefaultCompilerAdapter {

     * Performs a compile using the Javac externally.
     * @return true if the compilation succeeded
     * @throws BuildException on error
    public boolean execute() throws BuildException {
        attributes.log("Using external javac compiler", Project.MSG_VERBOSE);

        Commandline cmd = new Commandline();
        if (!assumeJava11() && !assumeJava12()) {
        } else {
            setupJavacCommandlineSwitches(cmd, true);
        int firstFileName = assumeJava11() ? -1 : cmd.size();
        //On VMS platform, we need to create a special java options file
        //containing the arguments and classpath for the javac command.
        //The special file is supported by the "-V" switch on the VMS JVM.
        if (Os.isFamily("openvms")) {
            return execOnVMS(cmd, firstFileName);
                executeExternalCompile(cmd.getCommandline(), firstFileName,
                == 0;

     * helper method to execute our command on VMS.
     * @param cmd
     * @param firstFileName
     * @return
    private boolean execOnVMS(Commandline cmd, int firstFileName) {
        File vmsFile = null;
        try {
            vmsFile = JavaEnvUtils.createVmsJavaOptionFile(cmd.getArguments());
            String[] commandLine = {cmd.getExecutable(),
            return 0 == executeExternalCompile(commandLine,

        } catch (IOException e) {
            throw new BuildException("Failed to create a temporary file for \"-V\" switch");
        } finally {


Other Ant examples (source code examples)

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