org.jboss.tools.jst.web.kb.internal.scanner.ClassPathMonitor.java Source code

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/******************************************************************************* 
 * Copyright (c) 2007 Red Hat, Inc. 
 * Distributed under license by Red Hat, Inc. All rights reserved. 
 * This program is made available under the terms of the 
 * Eclipse Public License v1.0 which accompanies this distribution, 
 * and is available at http://www.eclipse.org/legal/epl-v10.html 
 * 
 * Contributors: 
 * Red Hat, Inc. - initial API and implementation 
 ******************************************************************************/
package org.jboss.tools.jst.web.kb.internal.scanner;

import java.io.File;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.jdt.core.IClasspathEntry;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.JavaCore;
import org.jboss.tools.common.model.XJob;
import org.jboss.tools.common.model.XJob.XRunnable;
import org.jboss.tools.common.model.XModelObject;
import org.jboss.tools.common.model.filesystems.FileSystemsHelper;
import org.jboss.tools.common.model.plugin.ModelPlugin;
import org.jboss.tools.common.model.project.ext.AbstractClassPathMonitor;
import org.jboss.tools.common.model.util.EclipseResourceUtil;
import org.jboss.tools.jst.web.WebModelPlugin;
import org.jboss.tools.jst.web.kb.IKbProject;
import org.jboss.tools.jst.web.kb.KbProjectFactory;
import org.jboss.tools.jst.web.kb.WebKbPlugin;
import org.jboss.tools.jst.web.kb.internal.KbProject;
import org.jboss.tools.jst.web.model.helpers.InnerModelHelper;

/**
 * Monitors class path of project and loads kb components of it.
 *  
 * @author Viacheslav Kabanovich
 */
public class ClassPathMonitor extends AbstractClassPathMonitor<KbProject> {

    /**
     * Creates instance of class path for kb project
     * @param project
     */
    public ClassPathMonitor(KbProject project) {
        this.project = project;
    }

    /**
     * Initialization of inner model.
     */
    public void init() {
        model = InnerModelHelper.createXModel(project.getProject());
        super.init();
    }

    public IProject getProjectResource() {
        return project.getProject();
    }

    boolean isProcessed = false;

    /**
     * Loads kb components from items recently added to class path. 
     */
    public void process() {
        isProcessed = true;
        try {
            doProcess();
        } finally {
            isProcessed = false;
        }
    }

    protected void doProcess() {
        if (paths == null) {
            ModelPlugin.getDefault().logError("Failed to process class path in kb builder for project " + project);
            return;
        }
        for (String p : syncProcessedPaths()) {
            project.pathRemoved(new Path(p));
        }
        for (int i = 0; i < paths.size(); i++) {
            String p = paths.get(i);
            if (!requestForLoad(p))
                continue;

            LibraryScanner scanner = new LibraryScanner();

            String fileName = new File(p).getName();
            if (EclipseResourceUtil.SYSTEM_JAR_SET.contains(fileName))
                continue;

            XModelObject o = FileSystemsHelper.getLibs(model).getLibrary(p);
            if (o == null)
                continue;

            LoadedDeclarations c = null;
            try {
                if (scanner.isLikelyComponentSource(o)) {
                    c = scanner.parse(o, new Path(p), project);
                }
            } catch (ScannerException e) {
                WebModelPlugin.getDefault().logError(e);
            }
            if (c == null) {
                c = new LoadedDeclarations();
            }
            componentsLoaded(c, new Path(p));
        }

        validateProjectDependencies();
    }

    public void waitProcess() {
        int count = 0;
        while (isProcessed) {
            try {
                synchronized (this) {
                    wait(100);
                }
                count++;
                if (count >= 50) {
                    String message = "Failed to wait for class path build";
                    WebKbPlugin.getDefault().logWarning(message, new Exception(message));
                    break;
                }
            } catch (InterruptedException e) {
                WebKbPlugin.getDefault().logError(e);
                break;
            }
        }
    }

    public void validateProjectDependencies() {
        List<KbProject> ps = null;

        try {
            ps = getKbProjects(project.getProject());
        } catch (CoreException e) {
            WebModelPlugin.getDefault().logError(e);
        }
        if (ps != null) {
            Set<KbProject> set = project.getKbProjects();
            Set<KbProject> removable = new HashSet<KbProject>();
            removable.addAll(set);
            removable.removeAll(ps);
            ps.removeAll(set);
            for (KbProject p : ps) {
                project.addKbProject(p);
            }
            for (KbProject p : removable) {
                project.removeKbProject(p);
            }
        }
    }

    public boolean hasToUpdateProjectDependencies() {
        try {
            List<KbProject> ps = getKbProjects(project.getProject());
            Set<KbProject> set = project.getKbProjects();
            if (set.size() != ps.size()) {
                return true;
            }
            for (KbProject p : ps) {
                if (!set.contains(p))
                    return true;
            }
        } catch (CoreException e) {
            WebModelPlugin.getDefault().logError(e);
        }
        return false;
    }

    void componentsLoaded(LoadedDeclarations c, IPath path) {
        if (c == null)
            return;
        project.registerComponents(c, path);
    }

    List<KbProject> getKbProjects(IProject project) throws CoreException {
        List<KbProject> list = new ArrayList<KbProject>();
        if (project.isAccessible() && project.hasNature(JavaCore.NATURE_ID)) {
            IJavaProject javaProject = JavaCore.create(project);
            IClasspathEntry[] es = javaProject.getResolvedClasspath(true);
            for (int i = 0; i < es.length; i++) {
                if (es[i].getEntryKind() == IClasspathEntry.CPE_PROJECT) {
                    IProject p = ResourcesPlugin.getWorkspace().getRoot().getProject(es[i].getPath().lastSegment());
                    if (p == null || !p.isAccessible())
                        continue;
                    KbProject.checkKBBuilderInstalled(p);
                    IKbProject sp = KbProjectFactory.getKbProject(p, false);
                    if (sp != null)
                        list.add((KbProject) sp);
                }
            }

        }
        return list;
    }

    public void build() {
        waitProcess();
        if (update()) {
            process();
        } else if (hasToUpdateProjectDependencies()) {
            validateProjectDependencies();
        }
    }

    public void pathsChanged(List<String> paths) {
        super.pathsChanged(paths);
        if (project.isStorageResolved()) {
            XJob.addRunnableWithPriority(new XRunnable() {

                public void run() {
                    if (!isProcessed && update()) {
                        //                  System.out.println("Running " + getId());
                        process();
                    }
                }

                public String getId() {
                    return "Update class path of kb project " + project.getProject().getName(); //$NON-NLS-1$
                }
            });
        }
    }
}