Ant example source code file (WLJspc.java)

This example Ant source code file (WLJspc.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, file, file, io, java, jsp, path, path, string, string, stringtokenizer, util, vector, warning, wljspc

The WLJspc.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;

//apache/ant imports
import java.io.File;
import java.util.Date;
import java.util.StringTokenizer;
import java.util.Vector;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.DirectoryScanner;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.taskdefs.Java;
import org.apache.tools.ant.taskdefs.MatchingTask;
import org.apache.tools.ant.types.Path;

/**
 * Precompiles JSP's using WebLogic's JSP compiler (weblogic.jspc).
 *
 * Tested only on Weblogic 4.5.1 - NT4.0 and Solaris 5.7
 *
 * required attributes
 *      src : root of source tree for JSP, ie, the document root for your weblogic server
 *      dest : root of destination directory, what you have set as
 *             WorkingDir in the weblogic properties
 *      package : start package name under which your JSP's would be compiled
 *
 * other attributes
 *     classpath
 *
 * A classpath should be set which contains the weblogic classes as well as all
 * application classes referenced by the JSP. The system classpath is also
 * appended when the jspc is called, so you may choose to put everything in
 * the classpath while calling Ant. However, since presumably the JSP's will
 * reference classes being build by Ant, it would be better to explicitly add
 * the classpath in the task
 *
 * The task checks timestamps on the JSP's and the generated classes, and compiles
 * only those files that have changed.
 *
 * It follows the weblogic naming convention of putting classes in
 *  <b> _dirName/_fileName.class for dirname/fileName.jsp   
 *
 * Limitation: It compiles the files thru the Classic compiler only.
 * Limitation: Since it is my experience that weblogic jspc throws out of
 *             memory error on being given too many files at one go, it is
 *             called multiple times with one jsp file each.
 *
 * <pre>
 * example
 * <target name="jspcompile" depends="compile">
 *   <wljspc src="c:\\weblogic\\myserver\\public_html"
 *           dest="c:\\weblogic\\myserver\\serverclasses" package="myapp.jsp">
 *   <classpath>
 *          <pathelement location="${weblogic.classpath}" />
 *           <pathelement path="${compile.dest}" />
 *      </classpath>
 *
 *   </wljspc>
 * </target>
 * </pre>
 *
 */

public class WLJspc extends MatchingTask {
    //TODO Test on other versions of weblogic
    //TODO add more attributes to the task, to take care of all jspc options
    //TODO Test on Unix

    /** root of compiled files tree */
    private File destinationDirectory;

    /** root of source files tree */
    private File sourceDirectory;

    /** package under which resultant classes will reside */
    private String destinationPackage;

    /** classpath used to compile the jsp files. */
    private Path compileClasspath;

    //private String compilerPath; //fully qualified name for the compiler executable

    private String pathToPackage = "";
    private Vector filesToDo = new Vector();

    /**
     * Run the task.
     * @throws BuildException if there is an error.
     */
    public void execute() throws BuildException {
        if (!destinationDirectory.isDirectory()) {
            throw new BuildException("destination directory "
                + destinationDirectory.getPath() + " is not valid");
        }

        if (!sourceDirectory.isDirectory()) {
            throw new BuildException("src directory "
                + sourceDirectory.getPath() + " is not valid");
        }

        if (destinationPackage == null) {
            throw new BuildException("package attribute must be present.",
                                     getLocation());
        }


        pathToPackage
            = this.destinationPackage.replace('.', File.separatorChar);
        // get all the files in the sourceDirectory
        DirectoryScanner ds = super.getDirectoryScanner(sourceDirectory);

        //use the systemclasspath as well, to include the ant jar
        if (compileClasspath == null) {
            compileClasspath = new Path(getProject());
        }

        compileClasspath = compileClasspath.concatSystemClasspath();
        String[] files = ds.getIncludedFiles();

        //Weblogic.jspc calls System.exit() ... have to fork
        // Therefore, takes loads of time
        // Can pass directories at a time (*.jsp) but easily runs out of
        // memory on hefty dirs (even on  a Sun)
        Java helperTask = new Java(this);
        helperTask.setFork(true);
        helperTask.setClassname("weblogic.jspc");
        helperTask.setTaskName(getTaskName());
        String[] args = new String[12];

        File jspFile = null;
        String parents = "";
        int j = 0;
        //XXX  this array stuff is a remnant of prev trials.. gotta remove.
        args[j++] = "-d";
        args[j++] = destinationDirectory.getAbsolutePath().trim();
        args[j++] = "-docroot";
        args[j++] = sourceDirectory.getAbsolutePath().trim();
        args[j++] = "-keepgenerated";  //TODO: Parameterise ??
        //Call compiler as class... dont want to fork again
        //Use classic compiler -- can be parameterised?
        args[j++] =  "-compilerclass";
        args[j++] = "sun.tools.javac.Main";
        //Weblogic jspc does not seem to work unless u explicitly set this...
        // Does not take the classpath from the env....
        // Am i missing something about the Java task??
        args[j++] = "-classpath";
        args[j++] = compileClasspath.toString();

        this.scanDir(files);
        log("Compiling " + filesToDo.size() + " JSP files");

        for (int i = 0; i < filesToDo.size(); i++) {
            //XXX
            // All this to get package according to weblogic standards
            // Can be written better... this is too hacky!
            // Careful.. similar code in scanDir , but slightly different!!
            String filename = (String) filesToDo.elementAt(i);
            jspFile = new File(filename);
            args[j] = "-package";
            parents = jspFile.getParent();
            if ((parents != null)  && (!("").equals(parents))) {
                parents =  this.replaceString(parents, File.separator, "_.");
                args[j + 1] = destinationPackage + "." + "_" + parents;
            } else {
                args[j + 1] = destinationPackage;
            }


            args[j + 2] =  sourceDirectory + File.separator + filename;
            helperTask.clearArgs();

            for (int x = 0; x < j + 3; x++) {
                helperTask.createArg().setValue(args[x]);
            }

            helperTask.setClasspath(compileClasspath);
            if (helperTask.executeJava() != 0) {
                log(filename + " failed to compile", Project.MSG_WARN);
            }
        }
    }



    /**
     * Set the classpath to be used for this compilation.
     * @param classpath the classpath to use.
     */
    public void setClasspath(Path classpath) {
        if (compileClasspath == null) {
            compileClasspath = classpath;
        } else {
            compileClasspath.append(classpath);
        }
    }

    /**
     * Maybe creates a nested classpath element.
     * @return a path to be configured.
     */
    public Path createClasspath() {
        if (compileClasspath == null) {
            compileClasspath = new Path(getProject());
        }
        return compileClasspath;
    }

    /**
     * Set the directory containing the source jsp's
     *
     *
     * @param dirName the directory containg the source jsp's
     */
    public void setSrc(File dirName) {

        sourceDirectory = dirName;
    }

     /**
     * Set the directory containing the source jsp's
     *
     *
     * @param dirName the directory containg the source jsp's
     */
    public void setDest(File dirName) {

        destinationDirectory = dirName;
    }

    /**
     * Set the package under which the compiled classes go
     *
     * @param packageName the package name for the clases
     */
    public void setPackage(String packageName) {

        destinationPackage = packageName;
    }

    /**
     * Scan the array of files and add the jsp
     * files that need to be compiled to the filesToDo field.
     * @param files the files to scan.
     */
    protected void scanDir(String[] files) {

        long now = (new Date()).getTime();
        File jspFile = null;
        String parents = null;
        String pack = "";
        for (int i = 0; i < files.length; i++) {
            File srcFile = new File(this.sourceDirectory, files[i]);
            //XXX
            // All this to convert source to destination directory according
            // to weblogic standards Can be written better... this is too hacky!
            jspFile = new File(files[i]);
            parents = jspFile.getParent();

            if ((parents != null)  && (!("").equals(parents))) {
                parents =  this.replaceString(parents, File.separator, "_/");
                pack = pathToPackage + File.separator + "_" + parents;
            } else {
                pack = pathToPackage;
            }

            String filePath = pack + File.separator + "_";
            int startingIndex = files[i].lastIndexOf(File.separator) != -1
                    ? files[i].lastIndexOf(File.separator) + 1 : 0;
            int endingIndex = files[i].indexOf(".jsp");
            if (endingIndex == -1) {
                log("Skipping " + files[i] + ". Not a JSP",
                    Project.MSG_VERBOSE);
                continue;
            }

            filePath += files[i].substring(startingIndex, endingIndex);
            filePath += ".class";
            File classFile = new File(this.destinationDirectory, filePath);

            if (srcFile.lastModified() > now) {
                log("Warning: file modified in the future: "
                    + files[i], Project.MSG_WARN);
            }
            if (srcFile.lastModified() > classFile.lastModified()) {
                filesToDo.addElement(files[i]);
                log("Recompiling File " + files[i], Project.MSG_VERBOSE);
            }
        }
    }


    /**
     * Replace occurances of a string with a replacement string.
     * @param inpString the string to convert.
     * @param escapeChars the string to replace.
     * @param replaceChars the string to place.
     * @return the converted string.
     */
    protected String replaceString(String inpString, String escapeChars,
                                   String replaceChars) {
        String localString = "";
        int numTokens = 0;
        StringTokenizer st = new StringTokenizer(inpString, escapeChars, true);
        numTokens = st.countTokens();
        for (int i = 0; i < numTokens; i++) {
            String test = st.nextToken();
            test = (test.equals(escapeChars) ? replaceChars : test);
            localString += test;
        }
        return localString;
    }
}