search/org/eclipse/jdt/internal/core/search/indexing/IndexManager.java

package org.eclipse.jdt.internal.core.search.indexing;

/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */

import org.eclipse.core.resources.*;
import org.eclipse.core.runtime.*;

import org.eclipse.jdt.core.*;
import org.eclipse.jdt.internal.core.index.*;
import org.eclipse.jdt.core.search.*;
import org.eclipse.jdt.internal.core.search.indexing.*;
import org.eclipse.jdt.internal.core.search.Util;
import org.eclipse.jdt.internal.core.search.processing.*;
import org.eclipse.jdt.internal.core.*;
import org.eclipse.jdt.internal.core.index.impl.*;

import org.eclipse.jdt.core.JavaCore;

import java.io.*;
import java.util.*;
import java.util.zip.*;

public class IndexManager extends JobManager implements IIndexConstants {
	/* number of file contents in memory */
	public static int MAX_FILES_IN_MEMORY = 0;
	
	public IWorkspace workspace;

	/* indexes */
	Hashtable indexes = new Hashtable(5);

	/* read write monitors */
	private Hashtable monitors = new Hashtable(5);

	/* need to save ? */
	private boolean needToSave = false;
	private static final CRC32 checksumCalculator = new CRC32();
	private IPath javaPluginLocation = null;
/**
 * Before processing all jobs, need to ensure that the indexes are up to date.
 */
public void activateProcessing() {
	try {
		Thread.currentThread().sleep(10000); // wait 10 seconds so as not to interfere with plugin startup
	} catch (InterruptedException ie) {
	}	
	checkIndexConsistency();
	super.activateProcessing();
}
/**
 * Trigger addition of a resource to an index
 * Note: the actual operation is performed in background
 */
public void add(IFile resource){
	if (JavaCore.getPlugin() == null || this.workspace == null) return;	
	String extension = resource.getFileExtension();
	if ("java"/*nonNLS*/.equals(extension)){
		AddCompilationUnitToIndex job = new AddCompilationUnitToIndex(resource, this);
		if (this.awaitingJobsCount() < MAX_FILES_IN_MEMORY) {
			job.initializeContents();
		}
		request(job);
	} else if ("class"/*nonNLS*/.equals(extension)){
		AddClassFileToIndex job = new AddClassFileToIndex(resource, this);
		if (this.awaitingJobsCount() < MAX_FILES_IN_MEMORY) {
			job.initializeContents();
		}
		request(job);
	}
}
/**
 * Ensures that indexes are up to date with workbench content. Typically
 * it is invoked in background when activate the job processing.
 */
public void checkIndexConsistency() {

	if (VERBOSE) System.out.println("STARTING - ensuring consistency"/*nonNLS*/);

	boolean wasEnabled = isEnabled();	
	try {
		disable();

		if (this.workspace == null) return;
		IProject[] projects = this.workspace.getRoot().getProjects();
		for (int i = 0, max = projects.length; i < max; i++){
			IProject project = projects[i];
			// not only java project, given at startup nature may not have been set yet
			if (project.isOpen()) { 
				indexAll(project);
			}
		}
	} finally {
		if (wasEnabled) enable();
		if (VERBOSE) System.out.println("DONE - ensuring consistency"/*nonNLS*/);
	}
}
private String computeIndexName(String pathString) {
	byte[] pathBytes = pathString.getBytes();
	checksumCalculator.reset();
	checksumCalculator.update(pathBytes);
	String fileName = Long.toString(checksumCalculator.getValue()) + ".index"/*nonNLS*/;
	if (VERBOSE) System.out.println(" index name: "/*nonNLS*/ + pathString + " <----> "/*nonNLS*/ + fileName);
	IPath indexPath = getJavaPluginWorkingLocation();
	String indexDirectory = indexPath.toOSString();
	if (indexDirectory.endsWith(File.separator)) {
		return indexDirectory + fileName;
	} else {
		return indexDirectory + File.separator + fileName;
	} 
}
/**
 * About to delete a project.
 */
public void deleting(IProject project) {
	discardJobsUntilNextProjectAddition(project.getName());

	IPath path = project.getFullPath();
	IIndex index = (IIndex) indexes.get(path);
	if (index != null){
		indexes.remove(path);
		monitors.remove(index);
	}
}
/**
 * Remove the index from cache for a given project.
 * Passing null as a job family discards them all.
 */
public void discardJobsUntilNextProjectAddition(String jobFamily) {
	boolean wasEnabled = isEnabled();
	try {
		disable();

		// wait until current job has completed
		while (thread != null && executing){
			try {
				Thread.currentThread().sleep(50);
			} catch(InterruptedException e){
			}
		}

		// flush and compact awaiting jobs
		int loc = -1;
		boolean foundProjectAddition = false;
		for (int i = jobStart; i <= jobEnd; i++){
			IJob currentJob = awaitingJobs[i];
			awaitingJobs[i] = null;
			if (jobFamily == null) continue; // discard
			if (currentJob.belongsTo(jobFamily)){ // might discard
				if (!(foundProjectAddition || (foundProjectAddition = currentJob instanceof IndexAllProject))) continue; // discard
			}
			awaitingJobs[++loc] = currentJob;
		}
		jobStart = 0;
		jobEnd = loc;
	} finally {
		if (wasEnabled)	enable();
	}
}
/**
 * Returns the index for a given project, if none then create an empty one.
 * Note: if there is an existing index file already, it will be reused. 
 * Warning: Does not check whether index is consistent (not being used)
 */
public IIndex getIndex(IPath path) {
	return this.getIndex(path, true);
}
/**
 * Returns the index for a given project, if none and asked for then create an empty one.
 * Note: if there is an existing index file already, it will be reused. 
 * Warning: Does not check whether index is consistent (not being used)
 */
public synchronized IIndex getIndex(IPath path, boolean mustCreate) {
	IIndex index = (IIndex) indexes.get(path);
	if (index == null) {
		try {
			// Compute canonical path
			IPath canonicalPath = JavaProject.canonicalizedPath(path);
			index = (IIndex) indexes.get(canonicalPath);
			if (!mustCreate) return index;
			if (index == null) {
				// New index: add same index for given path and canonical path
				String indexPath = computeIndexName(canonicalPath.toOSString());
				index = IndexFactory.newIndex(indexPath, "Index for "/*nonNLS*/ + canonicalPath.toOSString());
				indexes.put(canonicalPath, index);
				indexes.put(path, index);
				monitors.put(index, new ReadWriteMonitor());
			} else {
				// Index existed for canonical path, add it for given path
				indexes.put(path, index);
			}
		} catch (IOException e) {
			// The file could not be created. Possible reason: the project has been deleted.
			return null;
		}
	}
	//System.out.println(" index name: " + path.toOSString() + " <----> " + index.getIndexFile().getName());	
	return index;
}
private IPath getJavaPluginWorkingLocation() {
	if (javaPluginLocation == null) {
		javaPluginLocation = JavaCore.getPlugin().getStateLocation();
	}
	return javaPluginLocation;
}
/**
 * Index access is controlled through a read-write monitor so as
 * to ensure there is no concurrent read and write operations
 * (only concurrent reading is allowed).
 */
public ReadWriteMonitor getMonitorFor(IIndex index){
	
	return (ReadWriteMonitor)monitors.get(index);
}
/**
 * Trigger addition of the entire content of a project
 * Note: the actual operation is performed in background 
 */
public void indexAll(IProject project){
	if (JavaCore.getPlugin() == null || this.workspace == null) return;

	// Also request indexing of binaries on the classpath
	// determine the new children
	try {
		IJavaModel model = JavaModelManager.getJavaModel(this.workspace);
		IJavaProject javaProject = ((JavaModel) model).getJavaProject(project);	
		IClasspathEntry[] entries = javaProject.getResolvedClasspath(true);	
		for (int i = 0; i < entries.length; i++) {
			IClasspathEntry entry= entries[i];
			if (entry.getEntryKind() == IClasspathEntry.CPE_LIBRARY){
				indexJarFile(entry.getPath(), project.getName());
			}
		}
	} catch(JavaModelException e){ // cannot retrieve classpath info
	}	
	request(new IndexAllProject(project, this));
}
/**
 * Advance to the next available job, once the current one has been completed.
 * Note: clients awaiting until the job count is zero are still waiting at this point.
 */
protected synchronized void moveToNextJob() {

	// remember that one job was executed, and we will need to save indexes at some point
	needToSave = true;
	super.moveToNextJob();
}
/**
 * No more job awaiting.
 */
protected void notifyIdle(long idlingTime){
	if (idlingTime > 1000 && needToSave) saveIndexes();
}
/**
 * Name of the background process
 */
public String processName(){
	return Util.bind("process.name"/*nonNLS*/, IndexManager.class.getName());
}
/**
 * Recreates the index for a given path, keeping the same read-write monitor.
 * Returns the new empty index or null if it didn't exist before.
 * Warning: Does not check whether index is consistent (not being used)
 */
public synchronized IIndex recreateIndex(IPath path) {
	IIndex index = (IIndex) indexes.get(path);
	if (index != null) {
		try {
			// Compute canonical path
			IPath canonicalPath = JavaProject.canonicalizedPath(path);
			// Add same index for given path and canonical path
			String indexPath = computeIndexName(canonicalPath.toOSString());
			ReadWriteMonitor monitor = (ReadWriteMonitor)monitors.remove(index);
			index = IndexFactory.newIndex(indexPath, "Index for "/*nonNLS*/ + canonicalPath.toOSString());
			index.empty();
			indexes.put(canonicalPath, index);
			indexes.put(path, index);
			monitors.put(index, monitor);
		} catch (IOException e) {
			// The file could not be created. Possible reason: the project has been deleted.
			return null;
		}
	}
	//System.out.println(" index name: " + path.toOSString() + " <----> " + index.getIndexFile().getName());	
	return index;
}
/**
 * Trigger removal of a resource to an index
 * Note: the actual operation is performed in background
 */
public void remove(String resourceName, IProject project){
	request(new RemoveFromIndex(resourceName, project, this));
}
/**
 * Flush current state
 */
public void reset(){

	super.reset();
	if (indexes != null){
		indexes = new Hashtable(5);
		monitors = new Hashtable(5);
	}
	javaPluginLocation = null;
}
/**
 * Commit all index memory changes to disk
 */
public void saveIndexes(){
	Enumeration indexList = indexes.elements();
	while (indexList.hasMoreElements()){
		try {
			IIndex index = (IIndex)indexList.nextElement();
			if (index == null) continue; // index got deleted since acquired
			ReadWriteMonitor monitor = getMonitorFor(index);
			if (monitor == null) continue; // index got deleted since acquired
			try {
				monitor.enterWrite();
				if (IndexManager.VERBOSE) System.out.println("-> merging index : "/*nonNLS*/+index.getIndexFile());
				index.save();
			} finally {
				monitor.exitWrite();
			}
		} catch(IOException e){
			// Index file has been deleted
		}
	}
	needToSave = false;
}

/**
 * Trigger addition of a resource to an index
 * Note: the actual operation is performed in background
 */
public void indexJarFile(IPath path, String projectName) {
	if (JavaCore.getPlugin() == null || this.workspace == null) return;

	Object target = JavaModel.getTarget(ResourcesPlugin.getWorkspace().getRoot(), path, true);
	
	if (target instanceof IFile) {
		request(new AddJarFileToIndex((IFile)target, this, projectName));
	} else if (target instanceof java.io.File){
		request(new AddJarFileToIndex(path, this, projectName));
	}
}
}