Ant example source code file (JasperC.java)

This example Ant source code file (JasperC.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

antclassloader, buildexception, buildexception, commandlinejava, commandlinejava, error, io, jasperc, jasperc, java, jspmangler, path, path, string, tomcat

The JasperC.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.optional.jsp.compilers;

import java.io.File;
import org.apache.tools.ant.AntClassLoader;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.taskdefs.Java;
import org.apache.tools.ant.taskdefs.optional.jsp.JspC;
import org.apache.tools.ant.taskdefs.optional.jsp.JspMangler;
import org.apache.tools.ant.types.CommandlineJava;
import org.apache.tools.ant.types.Path;

/**
 * The implementation of the jasper compiler.
 * This is a cut-and-paste of the original Jspc task.
 *
 * @since ant1.5
 */
public class JasperC extends DefaultJspCompilerAdapter {

    // CheckStyle:VisibilityModifier OFF - bc

    /**
     * what produces java classes from .jsp files
     */
    JspMangler mangler;

    // CheckStyle:VisibilityModifier ON

    /**
     * Constructor for JasperC.
     * @param mangler a filename converter
     */
    public JasperC(JspMangler mangler) {
        this.mangler = mangler;
    }

    /**
     * Our execute method.
     * @return true if successful
     * @throws BuildException on error
     */
    public boolean execute()
        throws BuildException {
        getJspc().log("Using jasper compiler", Project.MSG_VERBOSE);
        CommandlineJava cmd = setupJasperCommand();

        try {
            // Create an instance of the compiler, redirecting output to
            // the project log
            Java java = new Java(owner);
            Path p = getClasspath();
            if (getJspc().getClasspath() != null) {
                getProject().log("using user supplied classpath: " + p,
                                 Project.MSG_DEBUG);
            } else {
                getProject().log("using system classpath: " + p,
                                 Project.MSG_DEBUG);
            }
            java.setClasspath(p);
            java.setDir(getProject().getBaseDir());
            java.setClassname("org.apache.jasper.JspC");
            //this is really irritating; we need a way to set stuff
            String []args = cmd.getJavaCommand().getArguments();
            for (int i = 0; i < args.length; i++) {
                java.createArg().setValue(args[i]);
            }
            java.setFailonerror(getJspc().getFailonerror());
            //we are forking here to be sure that if JspC calls
            //System.exit() it doesn't halt the build
            java.setFork(true);
            java.setTaskName("jasperc");
            java.execute();
            return true;
        } catch (Exception ex) {
            if (ex instanceof BuildException) {
                throw (BuildException) ex;
            } else {
                throw new BuildException("Error running jsp compiler: ",
                                         ex, getJspc().getLocation());
            }
        } finally {
            getJspc().deleteEmptyJavaFiles();
        }
    }



    /**
     * build up a command line
     * @return a command line for jasper
     */
    private CommandlineJava setupJasperCommand() {
        CommandlineJava cmd = new CommandlineJava();
        JspC jspc = getJspc();
        addArg(cmd, "-d", jspc.getDestdir());
        addArg(cmd, "-p", jspc.getPackage());

        if (!isTomcat5x()) {
            addArg(cmd, "-v" + jspc.getVerbose());
        } else {
            getProject().log("this task doesn't support Tomcat 5.x properly, "
                             + "please use the Tomcat provided jspc task "
                             + "instead");
        }

        addArg(cmd, "-uriroot", jspc.getUriroot());
        addArg(cmd, "-uribase", jspc.getUribase());
        addArg(cmd, "-ieplugin", jspc.getIeplugin());
        addArg(cmd, "-webinc", jspc.getWebinc());
        addArg(cmd, "-webxml", jspc.getWebxml());
        addArg(cmd, "-die9");

        if (jspc.isMapped()) {
            addArg(cmd, "-mapped");
        }
        if (jspc.getWebApp() != null) {
            File dir = jspc.getWebApp().getDirectory();
            addArg(cmd, "-webapp", dir);
        }
        logAndAddFilesToCompile(getJspc(), getJspc().getCompileList(), cmd);
        return cmd;
    }

    /**
     * @return an instance of the mangler this compiler uses
     */

    public JspMangler createMangler() {
        return mangler;
    }

    /**
     * @since Ant 1.6.2
     */
    private Path getClasspath() {
        Path p = getJspc().getClasspath();
        if (p == null) {
            p = new Path(getProject());
            return p.concatSystemClasspath("only");
        } else {
            return p.concatSystemClasspath("ignore");
        }
    }

    /**
     * @since Ant 1.6.2
     */
    private boolean isTomcat5x() {
        AntClassLoader l = null;
        try {
            l = getProject().createClassLoader(getClasspath());
            l.loadClass("org.apache.jasper.tagplugins.jstl.If");
            return true;
        } catch (ClassNotFoundException e) {
            return false;
        } finally {
            if (l != null) {
                l.cleanup();
            }
        }
    }
}