/*
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package org.apache.tools.ant.taskdefs.optional.ejb;

import java.io.*;

import javax.ejb.deployment.EntityDescriptor;
import javax.ejb.deployment.DeploymentDescriptor;

import org.apache.tools.ant.*;
import org.apache.tools.ant.types.Path;

/**
 * A helper class which performs the actual work of the ejbc task.
 *
 * This class is run with a classpath which includes the weblogic tools and the home and remote
 * interface class files referenced in the deployment descriptors being processed.
 *
 * @author <a href="mailto:conor@cortexebusiness.com.au">Conor MacNeill</a>, Cortex ebusiness Pty Limited
 */
public class EjbcHelper implements Ejbc.Helper {
    /**
     * The root directory of the tree containing the serialised deployment desciptors. 
     */
    private File descriptorDirectory;
    
    /**
     * The directory where generated files are placed.
     */
    private File generatedFilesDirectory;
    
    /**
     * The name of the manifest file generated for the EJB jar.
     */
    private File manifestFile;
    
    /**
     * The classpath to be used in the weblogic ejbc calls. It must contain the weblogic
     * classes <b>and</b> the implementation classes of the home and remote interfaces.
     */
    private Path classpath;
    
    /**
     * The source directory for the home and remote interfaces. This is used to determine if
     * the generated deployment classes are out of date.
     */
    private File sourceDirectory;

    /**
     * The array of descriptor filenames to be processed
     */
    private String[] files;

    /**
     * The Ejbc task that this helper is helping
     */
    private Ejbc ejbcTask;
   
    /**
     * The names of the serialised deployment descriptors
     */
    String[] descriptors; 

    public EjbcHelper() {
    }
      
    public void initialize(Ejbc ejbcTask) {
        this.ejbcTask = ejbcTask;
    }

    /**
     * Set the directory from where the serialised deployment descriptors are
     * to be read.
     *
     * @param dir the directory containing the serialised deployment descriptors.
     */
    public void setDescriptorDir(File dir) {
        descriptorDirectory = dir;
    }
    
    /**
     * Set the directory into which the support classes, RMI stubs, etc are to be written
     *
     * @param dir the directory into which code is generated
     */
    public void setDest(File dir) {
        generatedFilesDirectory = dir;
    }

    /**
     * Set the generated manifest file. 
     *
     * For each EJB that is processed an entry is created in this file. This can then be used
     * to create a jar file for dploying the beans.
     *
     * @param manfestFilename the manifest file to be generated.
     */
    public void setManifest(File manifestFile) {
        this.manifestFile = manifestFile;
    }
    
    /**
     * Set the classpath to be used for this compilation.
     */
    public void setClasspath(Path classpath) {
        this.classpath = classpath;
    }

    /**
     * Set the list of desciptors which ar eto be processed.
     *
     * @param descriptors an array of serialised deployment descriptor filenames to be processed.
     */
    public void setDescriptors(String[] descriptors) {
        this.descriptors = descriptors;
    }



    /**
     * Set the directory containing the source code for the home interface, remote interface
     * and public key class definitions.
     *
     * @param dir the directory containg the source tree for the EJB's interface classes.
     */
    public void setSrc(File dir) {
        sourceDirectory = dir;
    }

    /**
     * Perform the weblogic compiles.
     */
    public void execute() throws BuildException {
        try {
            String manifest = "Manifest-Version: 1.0\n\n";
            for (int i = 0; i < descriptors.length; ++i) {
                String descriptorName = descriptors[i];
                File descriptorFile = new File(descriptorDirectory, descriptorName);
                
                if (isRegenRequired(descriptorFile)) {
                    ejbcTask.log("Running ejbc for " + descriptorFile.getName(), Project.MSG_INFO);
                    regenerateSupportClasses(descriptorFile);
                }
                else {
                    ejbcTask.log(descriptorFile.getName() + " is up to date", Project.MSG_VERBOSE);
                }
                manifest += "Name: " + descriptorFile.getName() + "\nEnterprise-Bean: True\n\n";
            }
            
            FileWriter fw = new FileWriter(manifestFile);
            PrintWriter pw = new PrintWriter(fw);
            pw.print(manifest);
            fw.flush();
            fw.close();
        }
        catch (IOException e) {
            throw new BuildException(e);
        }
    }


    /**
     * Determine if the weblogic EJB support classes need to be regenerated
     * for a given deployment descriptor.
     *
     * This process attempts to determine if the support classes need to be
     * rebuilt. It does this by examining only some of the support classes 
     * which are typically generated. If the ejbc task is interrupted generating
     * the support classes for a bean, all of the support classes should be removed
     * to force regeneration of the support classes.
     *
     * @param descriptorFile the serialised deployment descriptor
     *
     * @return true if the support classes need to be regenerated.
     *
     * @throws IOException if the descriptor file cannot be closed.
     */
    private boolean isRegenRequired(File descriptorFile) throws IOException {
        // read in the descriptor. Under weblogic, the descriptor is a weblogic
        // specific subclass which has references to the implementation classes.
        // These classes must, therefore, be in the classpath when the deployment
        // descriptor is loaded from the .ser file
        FileInputStream fis = null;
        try {
            fis = new FileInputStream(descriptorFile);
            ObjectInputStream ois = new ObjectInputStream(fis);
            DeploymentDescriptor dd = (DeploymentDescriptor)ois.readObject();
            fis.close();
            
            String homeInterfacePath = dd.getHomeInterfaceClassName().replace('.', '/') + ".java";
            String remoteInterfacePath = dd.getRemoteInterfaceClassName().replace('.', '/') + ".java";
            String primaryKeyClassPath = null;
            if (dd instanceof EntityDescriptor) {
                primaryKeyClassPath = ((EntityDescriptor)dd).getPrimaryKeyClassName().replace('.', '/') + ".java";;
            }
        
            File homeInterfaceSource = new File(sourceDirectory, homeInterfacePath);
            File remoteInterfaceSource = new File(sourceDirectory, remoteInterfacePath);
            File primaryKeyClassSource = null;
            if (primaryKeyClassPath != null) {
                primaryKeyClassSource = new File(sourceDirectory, remoteInterfacePath);
            }
            
            // are any of the above out of date. 
            // we find the implementation classes and see if they are older than any
            // of the above or the .ser file itself.
            String beanClassBase = dd.getEnterpriseBeanClassName().replace('.', '/');
            File ejbImplentationClass 
                = new File(generatedFilesDirectory, beanClassBase + "EOImpl.class");
            File homeImplementationClass 
                = new File(generatedFilesDirectory, beanClassBase + "HomeImpl.class");
            File beanStubClass 
                = new File(generatedFilesDirectory, beanClassBase + "EOImpl_WLStub.class");
                
            // if the implementation classes don;t exist regenerate                
            if (!ejbImplentationClass.exists() || !homeImplementationClass.exists() ||
                    !beanStubClass.exists()) {
                return true;
            }
                
            // Is the ser file or any of the source files newer then the class files.
            // firstly find the oldest of the two class files.
            long classModificationTime = ejbImplentationClass.lastModified();
            if (homeImplementationClass.lastModified() < classModificationTime) {
                classModificationTime = homeImplementationClass.lastModified();
            }
            if (beanStubClass.lastModified() < classModificationTime) {
                classModificationTime = beanStubClass.lastModified();
            }
            
            if (descriptorFile.lastModified() > classModificationTime ||
                    homeInterfaceSource.lastModified() > classModificationTime ||
                    remoteInterfaceSource.lastModified() > classModificationTime) {
                return true;
            }
            
            if (primaryKeyClassSource != null && 
                    primaryKeyClassSource.lastModified() > classModificationTime) {
                return true;
            }
        }
        catch (Throwable descriptorLoadException) {
            ejbcTask.log("Exception occurred reading " + descriptorFile.getName() + " - continuing", 
                          Project.MSG_WARN);
            // any problems - just regenerate
            return true;
        }
        finally {
            if (fis != null) {
                fis.close();
            }
        }
        
        return false;
    }

    /**
     * Perform the weblogic.ejbc call to regenerate the support classes.
     *
     * Note that this method relies on an undocumented -noexit option to the 
     * ejbc tool to stop the ejbc tool exiting the VM altogether.
     */
    private void regenerateSupportClasses(File descriptorFile) {
        Project project = ejbcTask.getProject();
        String javaHome = System.getProperty("java.home");

        String compiler = project.getProperty("build.compiler");
        String[] args = null;
        
        if (compiler.equalsIgnoreCase("jikes")) {
            Path execClassPath = new Path(project);
            if (Project.getJavaVersion() == Project.JAVA_1_1) {
                execClassPath.addExisting(new Path(project, System.getProperty("java.home")
                                          + "/lib/classes.zip"));
            } else {
                execClassPath.addExisting(new Path(project,
                                                System.getProperty("java.home")
                                                + "/lib/rt.jar"));
                // Just keep the old version as well and let addExisting
                // sort it out.
                execClassPath.addExisting(new Path(project,
                                                System.getProperty("java.home")
                                                + "/jre/lib/rt.jar"));
            }
            execClassPath.append(classpath);
    
            args = new String[] {"-noexit",
                                 "-keepgenerated",
                                 "-compiler", "Jikes",
                                 "-d", generatedFilesDirectory.getPath(),
                                 "-classpath", execClassPath.toString(), 
                                 descriptorFile.getPath()};
        }
        else {            
            args = new String[]{"-noexit",
                                "-keepgenerated",
                                "-d", generatedFilesDirectory.getPath(),
                                "-classpath", classpath.toString(), 
                                descriptorFile.getPath()};
        }
                                       
        try {
            weblogic.ejbc.main(args);
        }
        catch (Exception e) {
            e.printStackTrace();
            throw new BuildException(e);
        }
    }
}