Ant example source code file (Gcj.java)

This example Ant source code file (Gcj.java) is included in the DevDaily.com "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, can't, commandline, commandline, conflict_with_dash_c, d, gcj, o, path, path, string, string, using

The Gcj.java 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
 *
 *      http://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.compilers;


import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.types.Commandline;
import org.apache.tools.ant.types.Path;

/**
 * The implementation of the gcj compiler.
 * This is primarily a cut-and-paste from the jikes.
 *
 * @since Ant 1.4
 */
public class Gcj extends DefaultCompilerAdapter {

    /**
     * Performs a compile using the gcj compiler.
     * @return true if the compilation succeeded
     * @throws BuildException on error
     */
    public boolean execute() throws BuildException {
        Commandline cmd;
        attributes.log("Using gcj compiler", Project.MSG_VERBOSE);
        cmd = setupGCJCommand();

        int firstFileName = cmd.size();
        logAndAddFilesToCompile(cmd);

        return
            executeExternalCompile(cmd.getCommandline(), firstFileName) == 0;
    }

    /**
     * Set up the gcj commandline.
     * @return the command line
     */
    protected Commandline setupGCJCommand() {
        Commandline cmd = new Commandline();
        Path classpath = new Path(project);

        // gcj doesn't support bootclasspath dir (-bootclasspath)
        // so we'll emulate it for compatibility and convenience.
        Path p = getBootClassPath();
        if (p.size() > 0) {
            classpath.append(p);
        }

        // gcj doesn't support an extension dir (-extdir)
        // so we'll emulate it for compatibility and convenience.
        classpath.addExtdirs(extdirs);

        classpath.append(getCompileClasspath());

        // Gcj has no option for source-path so we
        // will add it to classpath.
        if (compileSourcepath != null) {
            classpath.append(compileSourcepath);
        } else {
            classpath.append(src);
        }

        String exec = getJavac().getExecutable();
        cmd.setExecutable(exec == null ? "gcj" : exec);

        if (destDir != null) {
            cmd.createArgument().setValue("-d");
            cmd.createArgument().setFile(destDir);

            if (!destDir.exists() && !destDir.mkdirs()) {
                throw new BuildException("Can't make output directories. "
                                         + "Maybe permission is wrong. ");
            }
        }

        cmd.createArgument().setValue("-classpath");
        cmd.createArgument().setPath(classpath);

        if (encoding != null) {
            cmd.createArgument().setValue("--encoding=" + encoding);
        }
        if (debug) {
            cmd.createArgument().setValue("-g1");
        }
        if (optimize) {
            cmd.createArgument().setValue("-O");
        }

        /**
         *  gcj should be set for generate class.
         * ... if no 'compile to native' argument is passed
         */
        if (!isNativeBuild()) {
            cmd.createArgument().setValue("-C");
        }

        addCurrentCompilerArgs(cmd);

        return cmd;
    }

    /**
     * Whether any of the arguments given via <compilerarg>
     * implies that compilation to native code is requested.
     * @return true if compilation to native code is requested
     * @since Ant 1.6.2
     */
    public boolean isNativeBuild() {
        boolean nativeBuild = false;
        String[] additionalArguments = getJavac().getCurrentCompilerArgs();
        int argsLength = 0;
        while (!nativeBuild && argsLength < additionalArguments.length) {
            int conflictLength = 0;
            while (!nativeBuild
                   && conflictLength < CONFLICT_WITH_DASH_C.length) {
                nativeBuild = (additionalArguments[argsLength].startsWith
                               (CONFLICT_WITH_DASH_C[conflictLength]));
                conflictLength++;
            }
            argsLength++;
        }
        return nativeBuild;
    }

    private static final String [] CONFLICT_WITH_DASH_C = {
        "-o" , "--main=", "-D", "-fjni", "-L"
    };

}