ProjectClassLoader.java

package org.jboss.tools.smooks.configuration.editors.utils;

import java.io.File;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IWorkspaceRoot;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.IPath;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.IPackageFragmentRoot;
import org.eclipse.jdt.core.JavaCore;
import org.eclipse.jdt.core.JavaModelException;

/**
 * This class code comes from HibernateSynchronizer
 * 
 * @author Dart Peng
 * 
 * @CreateTime Jul 21, 2008
 */
public class ProjectClassLoader extends URLClassLoader {

	public ProjectClassLoader(IJavaProject project) throws JavaModelException {
		super(getURLSFromProject(project, null, true), Thread.currentThread()
				.getContextClassLoader());
	}

	public ProjectClassLoader(IJavaProject project, URL[] extraUrls)
			throws JavaModelException {
		super(getURLSFromProject(project, extraUrls, true), Thread
				.currentThread().getContextClassLoader());
	}

	private static URL[] getURLSFromProject(IJavaProject project,
			URL[] extraUrls, boolean cludeRequiredProject)
			throws JavaModelException {
		if(project == null || !project.exists()){
			return new URL[]{};
		}
		List<URL> list = new ArrayList<URL>();
		if (null != extraUrls) {
			for (int i = 0; i < extraUrls.length; i++) {
				list.add(extraUrls[i]);
			}
		}

		IPackageFragmentRoot[] roots = project.getAllPackageFragmentRoots();
		if (cludeRequiredProject) {
			String[] requiredProjectNames = project.getRequiredProjectNames();
			for (int i = 0; i < requiredProjectNames.length; i++) {
				String requiredProjectName = requiredProjectNames[i];
				IProject requiredProject = ResourcesPlugin.getWorkspace()
						.getRoot().getProject(requiredProjectName);
				if (requiredProject != null && requiredProject.isOpen()) {
					IJavaProject jp = JavaCore.create(requiredProject);
					if (jp == null)
						continue;
					URL[] requeiredURL = getURLSFromProject(jp, extraUrls,
							false);
					if (requeiredURL == null)
						continue;
					for (int j = 0; j < requeiredURL.length; j++) {
						list.add(requeiredURL[j]);
					}
				}
			}
		}
		IPath installPath = ResourcesPlugin.getWorkspace().getRoot()
				.getLocation();
		for (int i = 0; i < roots.length; i++) {
			try {
				if (roots[i].isArchive()) {
					File f = new File(FileLocator.resolve(
							installPath.append(roots[i].getPath()).toFile()
									.toURL()).getFile());
					if (!f.exists()) {
						f = new File(FileLocator.resolve(
								roots[i].getPath().makeAbsolute().toFile()
										.toURL()).getFile());
					}
					if (!f.exists()) {
						IJavaElement javaElement = roots[i].getPrimaryElement();
						String jarName = javaElement.getElementName();
						IResource jarResource = project.getProject().findMember(jarName);

						if(jarResource != null) {
							f = jarResource.getRawLocation().toFile();
						}
					}

					list.add(f.toURL());
				} else {
					IPath path = roots[i].getJavaProject().getOutputLocation();
					if (path.segmentCount() > 1) {
						IWorkspaceRoot root = ResourcesPlugin.getWorkspace()
								.getRoot();
						path = root.getFolder(path).getLocation();
						list.add(path.toFile().toURL());
					} else {
						path = roots[i].getJavaProject().getProject()
								.getLocation();
						list.add(path.toFile().toURL());
					}
				}
			} catch (Exception e) {
				e.printStackTrace();
			}

		}

		URL[] urls = new URL[list.size()];
		int index = 0;
		for (Iterator<?> i = list.iterator(); i.hasNext(); index++) {
			urls[index] = (URL) i.next();
		}
		return urls;
	}
}