Code Generator for Eclipse Code

--- a
+++ b/branches/features2604767and2604769/ch.sahits.codegen.core/src/ch/sahits/codegen/core/java/ProjectClassLoaderV2.java
@@ -0,0 +1,259 @@
+package ch.sahits.codegen.core.java;
+
+import java.io.File;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Vector;
+
+import org.eclipse.core.resources.IWorkspaceRoot;
+import org.eclipse.core.runtime.IPath;
+import org.eclipse.jdt.core.IClasspathContainer;
+import org.eclipse.jdt.core.IClasspathEntry;
+import org.eclipse.jdt.core.IJavaProject;
+import org.eclipse.jdt.core.JavaCore;
+import org.eclipse.jdt.core.JavaModelException;
+
+import ch.sahits.codegen.core.util.WorkspaceFragmentProvider;
+
+/**
+ * This class loader searches first in the classpath of
+ * the current project and then in the classpath of all other
+ * projects of java nature on the workspace.
+ * 
+ * This ClassLoader should only be extended by a ClassLoader that
+ * tries to load classes from the bundles or the projects in some specific
+ * manner or from a third location
+ * @author Andi Hotz
+ * @since 1.2.0
+ */
+public class ProjectClassLoaderV2 extends ClassLoader {
+	/** project for which the class should be loaded */
+	private IJavaProject project;
+	/**
+	 * Initialize the project for witch the class should be loaded
+	 * @param jProject
+	 */
+	public ProjectClassLoaderV2(IJavaProject jProject){
+		super(ProjectClassLoaderV2.class.getClassLoader());
+		project=jProject;
+	}
+	
+	
+	
+	/**
+	 * @see java.lang.ClassLoader#findClass(java.lang.String)
+	 */
+	@Override
+	protected Class<?> findClass(String name) throws ClassNotFoundException {
+		List<URL> urls = getCPURLs4Project(project);
+		URL[] url = toArray(urls);
+		try {
+			return new URLClassLoader(url).loadClass(name);
+		} catch (ClassNotFoundException e){
+			// Check all projects
+			List<IJavaProject> projects = WorkspaceFragmentProvider.getOpenJavaProjects();
+			for (IJavaProject p : projects){
+				if (!p.getElementName().equals(project.getElementName())){
+					try{
+						urls = getCPURLs4Project(project);
+						url = toArray(urls);
+						return new URLClassLoader(url).loadClass(name);
+					} catch (ClassNotFoundException e1){
+						continue; 
+					}
+				}
+			}
+		}
+		// the class was not found in in any project
+		throw new ClassCastException("The class "+name+" could not be found in any project");
+	}
+
+
+	/**
+	 * Retrieve all classpahs urls for the project
+	 * @param jProject project
+	 * @return List of URLSs
+	 * @throws JavaModelException
+	 * @throws MalformedURLException
+	 */
+	private List<URL> getCPURLs4Project(IJavaProject jProject){
+		List<URL> urls = new ArrayList<URL>();
+		try {
+			urls = getCP4Container(jProject);
+		} catch (JavaModelException e1) {
+			// so don't add
+		} catch (MalformedURLException e1) {
+			// so don't add
+		}
+		try {
+			urls.addAll(getCP4Library(jProject));
+		} catch (JavaModelException e1) {
+			// so don't add
+		} catch (MalformedURLException e1) {
+			// so don't add
+		}
+		try {
+			urls.addAll(getCP4variable(jProject));
+		} catch (MalformedURLException e1) {
+			// so don't add
+		} catch (JavaModelException e1) {
+			// so don't add
+		}
+		try {
+			urls.addAll(getCP4Project(jProject));
+		} catch (JavaModelException e1) {
+			// so don't add
+		} catch (MalformedURLException e1) {
+			// so don't add
+		}
+		IPath p;
+		try {
+			p = jProject.getOutputLocation();
+			String prefix = WorkspaceFragmentProvider.getAbsolutWorkspacePath()+File.separator+p.toOSString()+File.separator;
+			File f = new File(prefix);
+			try {
+				urls.add(0, f.toURI().toURL());
+			} catch (MalformedURLException e) {
+				// so nothing happens
+			}
+		} catch (JavaModelException e1) {
+			// so don't add
+		}
+		return urls;
+	}
+
+
+
+	/**
+	 * Retrieve the class paths URLs from project
+	 * @param p project for which the container is to be lookedup
+	 * @return List of classpath URLs
+	 * @throws MalformedURLException
+	 * @throws JavaModelException
+	 */
+	private List<URL> getCP4Container(IJavaProject p) throws JavaModelException, MalformedURLException{
+		List<URL> url = new ArrayList<URL>();
+		IClasspathEntry[] entries = p.getRawClasspath();
+		Vector<IClasspathEntry> v = new Vector<IClasspathEntry>();
+		for (IClasspathEntry entry : entries){
+			if (entry.getEntryKind()==IClasspathEntry.CPE_CONTAINER){
+				IClasspathContainer cont = JavaCore.getClasspathContainer(entry.getPath(), project);
+				IClasspathEntry[] entries2 = cont.getClasspathEntries(); // contains entries of type CPE_LIBRARY and CPE_PROJECT
+				for (IClasspathEntry e2 : entries2){
+					v.add(e2);
+				}
+			}
+		}
+		return retrieveURLsFromClasspath(url, v);
+	}
+	/**
+	 * Retrieve the class paths URLs from project
+	 * @param p project for which the library is to be lookedup
+	 * @return List of classpath URLs
+	 * @throws MalformedURLException
+	 * @throws JavaModelException
+	 */
+	private List<URL> getCP4Library(IJavaProject p) throws JavaModelException, MalformedURLException{
+		int kind = IClasspathEntry.CPE_LIBRARY;
+		return retrieveURLsFromProject(p, kind);
+		
+	}
+	/**
+	 * Retrieve the class paths URLs from project by classpath entry
+	 * @param p project for which the variable is to be lookedup
+	 * @return List of classpath URLs
+	 * @throws MalformedURLException
+	 * @throws JavaModelException
+	 */
+	private List<URL> retrieveURLsFromProject(IJavaProject p, int kind)
+			throws JavaModelException, MalformedURLException {
+		List<URL> url = new ArrayList<URL>();
+		IClasspathEntry[] entries = p.getRawClasspath();
+		Vector<IClasspathEntry> v = new Vector<IClasspathEntry>();
+		for (IClasspathEntry entry : entries){
+			if (entry.getEntryKind()==kind){
+				v.add(entry);
+			}
+		}
+		return retrieveURLsFromClasspath(url, v);
+	}
+	/**
+	 * Retrieve the list of classpaths
+	 * @param url List of classpathes
+	 * @param v Vector of Classpath entries
+	 * @return List of URLs
+	 * @throws MalformedURLException
+	 */
+	private List<URL> retrieveURLsFromClasspath(List<URL> url,
+			Vector<IClasspathEntry> v) throws MalformedURLException {
+		IPath path;
+		String path2Workspace = WorkspaceFragmentProvider.getAbsolutWorkspacePath();
+		for (IClasspathEntry entry : v){
+			path = entry.getPath();
+			URL u=null;
+			if (isWorkspaceRelative(path)){
+				u = new File(path2Workspace+path.toOSString()).toURI().toURL();
+			} else {
+				u = new File(path.toOSString()).toURI().toURL();
+			}
+			url.add(u);
+		}
+		return url;
+	}
+	/**
+	 * Retrieve the class paths URLs from project
+	 * @param p project for which the project is to be lookedup
+	 * @return List of classpath URLs
+	 * @throws MalformedURLException
+	 * @throws JavaModelException
+	 */
+	private List<URL> getCP4Project(IJavaProject p) throws JavaModelException, MalformedURLException{
+		int kind = IClasspathEntry.CPE_PROJECT;
+		return retrieveURLsFromProject(p, kind);
+	}
+	/**
+	 * Retrieve the class paths URLs from project
+	 * @param p project for which the variable is to be lookedup
+	 * @return List of classpath URLs
+	 * @throws MalformedURLException
+	 * @throws JavaModelException
+	 */
+	private List<URL> getCP4variable(IJavaProject p) throws MalformedURLException, JavaModelException{
+		List<URL> url = new ArrayList<URL>();
+		IClasspathEntry[] entries = p.getRawClasspath();
+		Vector<IClasspathEntry> v = new Vector<IClasspathEntry>();
+		for (IClasspathEntry entry : entries){
+			if (entry.getEntryKind()==IClasspathEntry.CPE_VARIABLE){
+				v.add(JavaCore.getResolvedClasspathEntry(entry));
+			}
+		}
+		return retrieveURLsFromClasspath(url, v);
+	}
+	/**
+	 * Check wether the path can be seolved within the workspace
+	 * @param p Path to be checked
+	 * @return true if the path exists relative to the workspace
+	 */
+	private boolean isWorkspaceRelative(IPath p) {
+		assert(p!=null);
+		IWorkspaceRoot root = WorkspaceFragmentProvider.getWorkspace().getRoot();
+		return root.exists(p);		
+	}
+	/**
+	 * Convert a list of URLs into an array of URLs
+	 * @param urls List of URLs
+	 * @return Array of the same URLs
+	 */
+	private URL[] toArray(List<URL> urls) {
+		URL[] url;
+		url = new URL[urls.size()];
+		for (int i=0;i<url.length;i++){
+			url[i]=urls.get(i);
+		}
+		return url;
+	}
+
+}