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 * obtain a copy of the License at
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package org.glassfish.deployapi;

import java.io.*;
import java.util.jar.*;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.logging.Logger;
import java.util.logging.Level;

import javax.enterprise.deploy.shared.factories.DeploymentFactoryManager;
import javax.enterprise.deploy.spi.factories.DeploymentFactory;

import org.glassfish.deployment.common.DeploymentUtils;
import com.sun.enterprise.util.shared.ArchivistUtils;
import com.sun.logging.LogDomains;

/**
 * This singleton object is responsible to resolving all the 
 * DeploymentManagerFactory installed in the RI and register
 * them to the DeploymentManagerFactory
 *
 * @author Jerome Dochez
 */
public class DeploymentFactoryInstaller {
    
    private static DeploymentFactoryInstaller dfInstaller = null;
    
    private final String J2EE_DEPLOYMENT_MANAGER_REPOSITORY = "lib" + File.separator + "deployment";
    private static final String J2EE_DEPLOYMENT_MANAGER = "J2EE-DeploymentFactory-Implementation-Class";
    private static final String J2EE_HOME = "com.sun.enterprise.home";
    
    private static final Logger sLogger=LogDomains.getLogger(DeploymentUtils.class, LogDomains.DPL_LOGGER);

    /** Creates a single instance of DeploymentManagerFactoryResolver */
    private DeploymentFactoryInstaller() {
    }
    
    public static DeploymentFactoryInstaller getInstaller() {
    
        if (dfInstaller==null) {
            dfInstaller = new DeploymentFactoryInstaller();
            dfInstaller.initialize();
        }
        return dfInstaller;
    }
    
    /**
     * @return a list of installed deployment manager 
     * implementation archives
     */
    public File[] getListOfDeploymentFactoryFiles() {
        
        File repository = new File(System.getProperty("com.sun.aas.installRoot")+File.separator+
            J2EE_DEPLOYMENT_MANAGER_REPOSITORY);
        
        if (sLogger.isLoggable(Level.FINE)) {
            sLogger.fine("J2EE Deployment factory repository = " 
                    + repository.getAbsolutePath());
        }
        if (!repository.exists()) {
            sLogger.log(Level.SEVERE, "enterprise.deployment.backend.deplyomentManagerLoadFailure",
                new Object[] {"Cannot find any deployment manager"});
            return null;
        }
        
        return repository.listFiles();        
    }
    
    /**
     * Add a new deployment manager to our respository
     */
    public void addDeploymentFactory(File newDM) throws IOException {
        
        int number=1;
        // copy to the right location...
        File repository = new File(System.getProperty(J2EE_HOME)+File.separator+
            J2EE_DEPLOYMENT_MANAGER_REPOSITORY);
        File to = new File(repository, newDM.getName());
        while (to.exists()) {
            to = new File(repository, newDM.getName()+number);
            number++;
        }
        ArchivistUtils.copy(
            new BufferedInputStream(new FileInputStream(newDM)),
            new BufferedOutputStream(new FileOutputStream(to)));
        
        installDeploymentFactory(to);
    
    }
    
    
    protected void installDeploymentFactory(File installedDM) throws IOException {
        
        if (sLogger.isLoggable(Level.FINE)) {
            sLogger.fine("Installing Deployment factory = " 
                    + installedDM.getAbsolutePath());
        }
        
        // let's check first that we indeed have a valid 
        // deployment manager implementation
        
        /*
         *Declare the JarFile and Manifest but populate them inside the first try block.  This way the 
         *jar file can be closed right away to conserve resources.
         */
        JarFile jarFile = null;
        Manifest m = null;
        try {
            jarFile = new JarFile(installedDM);
            m = jarFile.getManifest();
        } finally {
            /*
             *The jarFile.close can throw IOException, but this method also throws that exception so there is no
             *need to catch it and wrap it here in the finally clause.
             */
            jarFile.close();
            jarFile = null;
        }
        String className = m.getMainAttributes().getValue(J2EE_DEPLOYMENT_MANAGER);
        URL[] urls = new URL[]{installedDM.toURI().toURL()};
        URLClassLoader urlClassLoader = new java.net.URLClassLoader(urls, getClass().getClassLoader());
        Class factory = null;
        try {
            factory=urlClassLoader.loadClass(className);
        } catch (ClassNotFoundException cnfe) {
            sLogger.log(Level.SEVERE, "enterprise.deployment.backend.deplyomentManagerLoadFailure",
                new Object[] {"Unable to load declared DeploymentManagerFactory"});
            throw new IllegalArgumentException(className + " is not present in the " + installedDM.getName());
        }
        
        // Ok we have the class, let's instanciate it, check it and 
        // if everything is fine, register it to the DeploymentFactoryManager
        Object df = null;
        try {            
            df = factory.newInstance();
        } catch (Exception ie) {
            sLogger.log(Level.SEVERE, "enterprise.deployment.backend.deplyomentManagerLoadFailure",
                    new Object[]{className});
            sLogger.log(Level.SEVERE, "Error occurred", ie);
            throw new IllegalArgumentException("Cannot install " + installedDM.getName());
        }
        if (df instanceof DeploymentFactory) {
            DeploymentFactoryManager.getInstance().registerDeploymentFactory((DeploymentFactory) df);
        } else {
            throw new IllegalArgumentException("The " + className + 
                " declared as a DeploymentFactory does implement the DeploymentFactory interface");
        }
    }
    
    protected void initialize() {
                
        File[] elligibleFiles = getListOfDeploymentFactoryFiles();
        if (elligibleFiles==null) {
            return;
        }
           
        for (int i=0;i<elligibleFiles.length;i++) {
            try {
                installDeploymentFactory(elligibleFiles[i]);
            } catch(Exception ioe) {
                sLogger.log(Level.SEVERE, "enterprise.deployment.backend.deplyomentManagerLoadFailure",
                    new Object[] {elligibleFiles[i].getName()});
                sLogger.log(Level.SEVERE, "Error occurred", ioe);
            }
        }        
    }       
}