Ant example source code file (JspC.java)

This example Ant source code file (JspC.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, compile, compiling, file, file, io, jspmangler, path, path, string, string, util, vector, warning, webappparameter

The JspC.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;

import java.io.File;
import java.util.Date;
import java.util.Enumeration;
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.MatchingTask;
import org.apache.tools.ant.taskdefs.optional.jsp.compilers.JspCompilerAdapter;
import org.apache.tools.ant.taskdefs.optional.jsp.compilers.JspCompilerAdapterFactory;
import org.apache.tools.ant.types.Path;
import org.apache.tools.ant.types.Reference;

/**
 * Runs a JSP compiler.
 *
 * <p> This task takes the given jsp files and compiles them into java
 * files. It is then up to the user to compile the java files into classes.
 *
 * <p> The task requires the srcdir and destdir attributes to be
 * set. This Task is a MatchingTask, so the files to be compiled can be
 * specified using includes/excludes attributes or nested include/exclude
 * elements. Optional attributes are verbose (set the verbosity level passed
 * to jasper), package (name of the destination package for generated java
 * classes and classpath (the classpath to use when running the jsp
 * compiler).
 * <p> This task supports the nested elements classpath (A Path) and
 * classpathref (A Reference) which can be used in preference to the
 * attribute classpath, if the jsp compiler is not already in the ant
 * classpath.
 *
 * <p>
Usage
 * <pre>
 * <jspc srcdir="${basedir}/src/war"
 *       destdir="${basedir}/gensrc"
 *       package="com.i3sp.jsp"
 *       verbose="9">
 *   <include name="**\/*.jsp" />
 * </jspc>
 * </pre>
 *
 * <p> Large Amount of cutting and pasting from the Javac task...
 * @since 1.5
 */
public class JspC extends MatchingTask {
    private Path classpath;
    private Path compilerClasspath;
    private Path src;
    private File destDir;
    private String packageName;
    /** name of the compiler to use */
    private String compilerName = "jasper";

    /**
     *  -ieplugin <clsid> Java Plugin classid for Internet Explorer
     */
    private String iepluginid;
    private boolean mapped;
    private int verbose = 0;
    // CheckStyle:VisibilityModifier OFF - bc
    protected Vector compileList = new Vector();
    Vector javaFiles = new Vector();

    /**
     *  flag to control action on execution trouble
     */
    protected boolean failOnError = true;

    /**
     *  -uriroot <dir> The root directory that uri files should be resolved
     *  against,
     */
    private File uriroot;

    /**
     *  -webinc <file> Creates partial servlet mappings for the -webapp option
     */
    private File webinc;

    /**
     *  -webxml <file> Creates a complete web.xml when using the -webapp option.
     */

    private File webxml;

    /**
     *  web apps
     */
    protected WebAppParameter webApp;



    private static final String FAIL_MSG
        = "Compile failed, messages should have been provided.";

    // CheckStyle:VisibilityModifier ON

    /**
     * Set the path for source JSP files.
     * @param srcDir the source path.
     */
    public void setSrcDir(Path srcDir) {
        if (src == null) {
            src = srcDir;
        } else {
            src.append(srcDir);
        }
    }

    /**
     * Get the source dir.
     * @return the source path.
     */
    public Path getSrcDir() {
        return src;
    }

    /**
     * Set the destination directory into which the JSP source
     * files should be compiled.
     * @param destDir the destination directory.
     */
    public void setDestdir(File destDir) {
        this.destDir = destDir;
    }

    /**
     * Get the destination directory.
     * @return the directory.
     */
    public File getDestdir() {
        return destDir;
    }

    /**
     * Set the name of the package the compiled jsp files should be in.
     * @param pkg the name of the package.
     */
    public void setPackage(String pkg) {
        this.packageName = pkg;
    }

    /**
     * Get the name of the package.
     * @return the package.
     */
    public String getPackage() {
        return packageName;
    }

    /**
     * Set the verbose level of the compiler
     * @param i the verbose level to use.
     */
    public void setVerbose(int i) {
        verbose = i;
    }

    /**
     * Get the verbose level.
     * @return the level.
     */
    public int getVerbose() {
        return verbose;
    }

    /**
     * Whether or not the build should halt if compilation fails.
     * Defaults to <code>true.
     * @param fail a <code>boolean value.
     */
    public void setFailonerror(boolean fail) {
        failOnError = fail;
    }
    /**
     * Gets the failonerror flag.
     * @return the flag.
     */
    public boolean getFailonerror() {
        return failOnError;
    }

    /**
     * Get the IE CLASSID value.
     * @return the value.
     */
    public String getIeplugin() {
        return iepluginid;
    }
    /**
     * Java Plugin CLASSID for Internet Explorer
     * @param iepluginid the id to use.
     */
    public void setIeplugin(String iepluginid) {
        this.iepluginid = iepluginid;
    }

    /**
     * If true, generate separate write() calls for each HTML line
     * in the JSP.
     * @return mapping status
     */
    public boolean isMapped() {
        return mapped;
    }

    /**
     * If true, generate separate write() calls for each HTML line
     * in the JSP.
     * @param mapped a <code>boolean value.
     */
    public void setMapped(boolean mapped) {
        this.mapped = mapped;
    }

    /**
     * The URI context of relative URI references in the JSP pages.
     * If it does not exist then it is derived from the location
     * of the file relative to the declared or derived value of uriroot.
     *
     * @param  uribase  The new Uribase value
     */
    public void setUribase(File uribase) {
        log("Uribase is currently an unused parameter", Project.MSG_WARN);
    }

    /**
     * Get the uri base value.
     * @return the value.
     */
    public File getUribase() {
        return uriroot;
    }

    /**
     *  The root directory that uri files should be resolved
     *  against. (Default is the directory jspc is invoked from)
     *
     * @param  uriroot  The new Uribase value
     */
    public void setUriroot(File uriroot) {
        this.uriroot = uriroot;
    }

    /**
     * Get the uri root value.
     * @return the value.
     */
    public File getUriroot() {
        return uriroot;
    }


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

    /**
     * Adds a path to the classpath.
     * @return a path to be configured.
     */
    public Path createClasspath() {
        if (classpath == null) {
            classpath = new Path(getProject());
        }
        return classpath.createPath();
    }

    /**
     * Adds a reference to a classpath defined elsewhere
     * @param r a reference to a classpath.
     */
    public void setClasspathRef(Reference r) {
        createClasspath().setRefid(r);
    }

    /**
     * Get the classpath.
     * @return the classpath.
     */
    public Path getClasspath() {
        return classpath;
    }

    /**
     * Set the classpath to be used to find this compiler adapter
     * @param cp the compiler classpath.
     */
    public void setCompilerclasspath(Path cp) {
        if (compilerClasspath == null) {
            compilerClasspath = cp;
        } else {
            compilerClasspath.append(cp);
        }
    }

    /**
     * get the classpath used to find the compiler adapter
     * @return the compiler classpath.
     */
    public Path getCompilerclasspath() {
        return compilerClasspath;
    }

    /**
     * Support nested compiler classpath, used to locate compiler adapter
     * @return a path to be configured.
     */
    public Path createCompilerclasspath() {
        if (compilerClasspath == null) {
            compilerClasspath = new Path(getProject());
        }
        return compilerClasspath.createPath();
    }

    /**
     *  Filename for web.xml.
     *
     * @param  webxml  The new Webxml value
     */
    public void setWebxml(File webxml) {
        this.webxml = webxml;
    }

    /**
     * Filename for web.xml.
     * @return The filename for web.xml.
     */
    public File getWebxml() {
        return this.webxml;
    }

    /**
     *  output filename for the fraction of web.xml that lists
     *  servlets.
     * @param  webinc  The new Webinc value
     */
    public void setWebinc(File webinc) {
        this.webinc = webinc;
    }

    /**
     * Get the webinc attribute.
     * @return the webinc attribute.
     */
    public File getWebinc() {
        return this.webinc;
    }

    /**
     * Adds a single webapp.
     *
     * @param  webappParam  add a web app parameter
     * @throws BuildException if more than one webapp is specified.
     */
    public void addWebApp(WebAppParameter webappParam)
        throws BuildException {
        //demand create vector of filesets
        if (webApp == null) {
            webApp = webappParam;
        } else {
            throw new BuildException("Only one webapp can be specified");
        }
    }

    /**
     * Get the web app.
     * @return the web app attribute.
     */
    public WebAppParameter getWebApp() {
        return webApp;
    }

    /**
     * Class name of a JSP compiler adapter.
     * @param compiler the compiler class name.
     */
    public void setCompiler(String compiler) {
        this.compilerName = compiler;
    }

    /**
    * get the list of files to compile
    * @return the list of files.
    */
    public Vector getCompileList() {
        return compileList;
    }

    /**
     * execute by building up a list of files that
     * have changed and hand them off to a jsp compiler
     * @throws BuildException on error.
     */
    public void execute()
        throws BuildException {

        // make sure that we've got a destdir
        if (destDir == null) {
            throw new BuildException("destdir attribute must be set!",
                                     getLocation());
        }

        if (!destDir.isDirectory()) {
            throw new BuildException("destination directory \"" + destDir
                    + "\" does not exist or is not a directory", getLocation());
        }

        File dest = getActualDestDir();

        //bind to a compiler
        JspCompilerAdapter compiler =
            JspCompilerAdapterFactory.getCompiler(compilerName, this,
                getProject().createClassLoader(compilerClasspath));

        //if we are a webapp, hand off to the compiler, which had better handle it
        if (webApp != null) {
            doCompilation(compiler);
            return;
        }

        // make sure that we've got a srcdir
        if (src == null) {
            throw new BuildException("srcdir attribute must be set!",
                                     getLocation());
        }
        String [] list = src.list();
        if (list.length == 0) {
            throw new BuildException("srcdir attribute must be set!",
                    getLocation());
        }


        // if the compiler does its own dependency stuff, we just call it right now
        if (compiler.implementsOwnDependencyChecking()) {
            doCompilation(compiler);
            return;
        }

        //the remainder of this method is only for compilers that need their dependency work done
        JspMangler mangler = compiler.createMangler();

        // scan source directories and dest directory to build up both copy
        // lists and compile lists
        resetFileLists();
        int filecount = 0;
        for (int i = 0; i < list.length; i++) {
            File srcDir = getProject().resolveFile(list[i]);
            if (!srcDir.exists()) {
                throw new BuildException("srcdir \"" + srcDir.getPath()
                    + "\" does not exist!", getLocation());
            }
            DirectoryScanner ds = this.getDirectoryScanner(srcDir);
            String[] files = ds.getIncludedFiles();
            filecount = files.length;
            scanDir(srcDir, dest, mangler, files);
        }

        // compile the source files

        log("compiling " + compileList.size() + " files", Project.MSG_VERBOSE);

        if (compileList.size() > 0) {

            log("Compiling " + compileList.size() + " source file"
                + (compileList.size() == 1 ? "" : "s")
                + " to "
                + dest);
            doCompilation(compiler);

        } else {
            if (filecount == 0) {
                log("there were no files to compile", Project.MSG_INFO);
            } else {
                log("all files are up to date", Project.MSG_VERBOSE);
            }
        }
    }

    /**
     * calculate where the files will end up:
     * this is destDir or it id destDir + the package name
     */
    private File getActualDestDir() {
        File dest = null;
        if (packageName == null) {
            dest = destDir;
        } else {
            String path = destDir.getPath() + File.separatorChar
                + packageName.replace('.', File.separatorChar);
            dest = new File(path);
        }
        return dest;
    }

    /**
     * do the compile
     */
    private void doCompilation(JspCompilerAdapter compiler)
            throws BuildException {
        // now we need to populate the compiler adapter
        compiler.setJspc(this);

        // finally, lets execute the compiler!!
        if (!compiler.execute()) {
            if (failOnError) {
                throw new BuildException(FAIL_MSG, getLocation());
            } else {
                log(FAIL_MSG, Project.MSG_ERR);
            }
        }
    }

    /**
     * Clear the list of files to be compiled and copied..
     */
    protected void resetFileLists() {
        compileList.removeAllElements();
    }

    /**
     * Scans the directory looking for source files to be compiled.
     * The results are returned in the class variable compileList
     * @param srcDir the source directory.
     * @param dest   the destination directory.
     * @param mangler the jsp filename mangler.
     * @param files   the file names to mangle.
     */
    protected void scanDir(
        File srcDir, File dest, JspMangler mangler, String[] files) {

        long now = (new Date()).getTime();

        for (int i = 0; i < files.length; i++) {
            String filename = files[i];
            File srcFile = new File(srcDir, filename);
            File javaFile = mapToJavaFile(mangler, srcFile, srcDir, dest);
            if (javaFile == null) {
                continue;
            }

            if (srcFile.lastModified() > now) {
                log("Warning: file modified in the future: " + filename,
                        Project.MSG_WARN);
            }
            boolean shouldCompile = false;
            shouldCompile = isCompileNeeded(srcFile, javaFile);
            if (shouldCompile) {
               compileList.addElement(srcFile.getAbsolutePath());
               javaFiles.addElement(javaFile);
            }
        }
    }

    /**
     * Test whether or not compilation is needed. A return value of
     * <code>true means yes, false means
     * our tests do not indicate this, but as the TLDs are
     * not used for dependency checking this is not guaranteed.
     * The current tests are
     * <ol>
     * <li>no dest file
     * <li>dest file out of date w.r.t source
     * <li>dest file zero bytes long
     * </ol>
     * @param srcFile JSP source file
     * @param javaFile JSP dest file
     * @return true if a compile is definately needed.
     *
     */
    private boolean isCompileNeeded(File srcFile, File javaFile) {
        boolean shouldCompile = false;
        if (!javaFile.exists()) {
            shouldCompile = true;
            log("Compiling " + srcFile.getPath()
                + " because java file " + javaFile.getPath()
                + " does not exist", Project.MSG_VERBOSE);
            } else {
                if (srcFile.lastModified() > javaFile.lastModified()) {
                    shouldCompile = true;
                    log("Compiling " + srcFile.getPath()
                        + " because it is out of date with respect to "
                        + javaFile.getPath(),
                        Project.MSG_VERBOSE);
                } else {
                    if (javaFile.length() == 0) {
                        shouldCompile = true;
                        log("Compiling " + srcFile.getPath()
                            + " because java file " + javaFile.getPath()
                            + " is empty", Project.MSG_VERBOSE);
                    }
                }
        }
        return shouldCompile;
    }


    /**
     * get a filename from our jsp file.
     * @param mangler the jsp filename managler.
     * @param srcFile the source file.
     * @param srcDir  the source directory.
     * @param dest    the destination directory.
     * @return the filename.
     * @todo support packages and subdirs
     */
    protected File mapToJavaFile(JspMangler mangler, File srcFile, File srcDir, File dest) {
        if (!srcFile.getName().endsWith(".jsp")) {
            return null;
        }
        String javaFileName = mangler.mapJspToJavaName(srcFile);
//        String srcFileDir=srcFile.getParent();
        return new File(dest, javaFileName);
    }

    /**
     * delete any java output files that are empty
     * this is to get around a little defect in jasper: when it
     * fails, it leaves incomplete files around.
     */
    public void deleteEmptyJavaFiles() {
        if (javaFiles != null) {
            Enumeration e = javaFiles.elements();
            while (e.hasMoreElements()) {
                File file = (File) e.nextElement();
                if (file.exists() && file.length() == 0) {
                    log("deleting empty output file " + file);
                    file.delete();
                }
            }
        }
    }

    /**
     * static inner class used as a parameter element
     */
    public static class WebAppParameter {

        /**
         * the sole option
         */
        private File directory;

        /**
         * query current directory
         * @return the directory.
         */
        public File getDirectory() {
            return directory;
        }

        /**
         * set directory; alternate syntax
         * @param directory the base dir.
         */
        public void setBaseDir(File directory) {
            this.directory = directory;
        }
    //end inner class
    }


//end class
}