model/org/eclipse/jdt/core/JavaCore.java

package org.eclipse.jdt.core;

/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */
 
import org.eclipse.core.runtime.*;
import org.eclipse.core.resources.*;

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

import org.eclipse.jdt.internal.compiler.*;
import org.eclipse.jdt.internal.compiler.env.*;
import org.eclipse.jdt.core.*;
import org.eclipse.jdt.internal.core.builder.*;
import org.eclipse.jdt.internal.core.*;
import org.eclipse.jdt.internal.core.builder.impl.*;
import org.eclipse.jdt.internal.core.builder.impl.ProblemFactory;
import org.eclipse.jdt.internal.core.search.indexing.*;

/**
 * The plug-in runtime class for the Java model plug-in containing the core
 * (UI-free) support for Java projects.
 * <p>
 * Like all plug-in runtime classes (subclasses of <code>Plugin</code>), this
 * class is automatically instantiated by the platform when the plug-in gets
 * activated. Clients must not attempt to instantiate plug-in runtime classes
 * directly.
 * </p>
 * <p>
 * The single instance of this class can be accessed from any plug-in declaring
 * the Java model plug-in as a prerequisite via 
 * <code>JavaCore.getJavaCore()</code>. The Java model plug-in will be activated
 * automatically if not already active.
 * </p>
 */
public final class JavaCore extends Plugin implements IExecutableExtension {


	private static Plugin JAVA_CORE_PLUGIN = null;
	/**
	 * The plug-in identifier of the Java core support
	 * (value <code>"org.eclipse.jdt.core"</code>).
	 */
	public static final String PLUGIN_ID = "org.eclipse.jdt.core"/*nonNLS*/; // getPlugin().getDescriptor().getUniqueIdentifier();

	/**
	 * The identifier for the Java builder
	 * (value <code>"org.eclipse.jdt.core.javabuilder"</code>).
	 */
	public static final String BUILDER_ID = PLUGIN_ID + ".javabuilder"/*nonNLS*/;

	/**
	 * The identifier for the Java model
	 * (value <code>"org.eclipse.jdt.core.javamodel"</code>).
	 */
	public static final String MODEL_ID = PLUGIN_ID + ".javamodel"/*nonNLS*/;

	/**
	 * The identifier for the Java nature
	 * (value <code>"org.eclipse.jdt.core.javanature"</code>).
	 * The presence of this nature on a project indicates that it is 
	 * Java-capable.
	 *
	 * @see org.eclipse.core.resources.IProject#hasNature
	 */
	public static final String NATURE_ID = PLUGIN_ID + ".javanature"/*nonNLS*/;

	/**
	 * Name of the handle id attribute in a Java marker
	 */
	private static final String ATT_HANDLE_ID= "org.eclipse.jdt.internal.core.JavaModelManager.handleId"/*nonNLS*/;

	/**
	 * Names of recognized configurable options
	 */
	public static final String COMPILER_LOCAL_VARIABLE_ATTR = PLUGIN_ID + ".compiler.debug.localVariable"/*nonNLS*/;
		// possible values are GENERATE or DO_NOT_GENERATE (default is DO_NOT_GENERATE)
		
	public static final String COMPILER_LINE_NUMBER_ATTR = PLUGIN_ID + ".compiler.debug.lineNumber"/*nonNLS*/;
		// possible values are  GENERATE or DO_NOT_GENERATE (default is GENERATE)
		
	public static final String COMPILER_SOURCE_FILE_ATTR = PLUGIN_ID + ".compiler.debug.sourceFile"/*nonNLS*/;
		// possible values are  GENERATE or DO_NOT_GENERATE (default is GENERATE)

	public static final String COMPILER_CODEGEN_UNUSED_LOCAL = PLUGIN_ID + ".compiler.codegen.unusedLocal"/*nonNLS*/;
		// possible values are PRESERVE or OPTIMIZE_OUT	(default is OPTIMIZE_OUT)

	public static final String COMPILER_CODEGEN_TARGET_PLATFORM = PLUGIN_ID + ".compiler.codegen.targetPlatform"/*nonNLS*/;
		// possible values are VERSION_1_1 or VERSION_1_2	(default is VERSION_1_1)

	public static final String COMPILER_PB_UNREACHABLE_CODE = PLUGIN_ID + ".compiler.problem.unreachableCode"/*nonNLS*/;
		// possible values are ERROR or WARNING	(default is ERROR)

	public static final String COMPILER_PB_INVALID_IMPORT = PLUGIN_ID + ".compiler.problem.invalidImport"/*nonNLS*/;
		// possible values are ERROR or WARNING	(default is ERROR)

	public static final String COMPILER_PB_OVERRIDING_PACKAGE_DEFAULT_METHOD = PLUGIN_ID + ".compiler.problem.overridingPackageDefaultMethod"/*nonNLS*/;
		// possible values are WARNING or IGNORE (default is WARNING)
		
	public static final String COMPILER_PB_METHOD_WITH_CONSTRUCTOR_NAME = PLUGIN_ID + ".compiler.problem.methodWithConstructorName"/*nonNLS*/;
		// possible values are WARNING or IGNORE (default is WARNING)

	public static final String COMPILER_PB_DEPRECATION = PLUGIN_ID + ".compiler.problem.deprecation"/*nonNLS*/;
		// possible values are WARNING or IGNORE (default is WARNING)

	public static final String COMPILER_PB_HIDDEN_CATCH_BLOCK = PLUGIN_ID + ".compiler.problem.hiddenCatchBlock"/*nonNLS*/;
		// possible values are WARNING or IGNORE (default is WARNING)

	public static final String COMPILER_PB_UNUSED_LOCAL = PLUGIN_ID + ".compiler.problem.unusedLocal"/*nonNLS*/;
		// possible values are WARNING or IGNORE (default is WARNING)

	public static final String COMPILER_PB_UNUSED_PARAMETER = PLUGIN_ID + ".compiler.problem.unusedParameter"/*nonNLS*/;
		// possible values are WARNING or IGNORE (default is WARNING)

	public static final String COMPILER_PB_SYNTHETIC_ACCESS_EMULATION = PLUGIN_ID + ".compiler.problem.syntheticAccessEmulation"/*nonNLS*/;
		// possible values are WARNING or IGNORE (default is IGNORE)	
	
	public static final String CORE_JAVA_BUILD_ORDER = PLUGIN_ID + ".computeJavaBuildOrder"/*nonNLS*/;
		// possible values are COMPUTE or IGNORE (default is COMPUTE)
	/**
	 * Possible values for configurable options
	 */
	public static final String GENERATE = "generate"/*nonNLS*/;
	public static final String DO_NOT_GENERATE = "do not generate"/*nonNLS*/;
	public static final String PRESERVE = "preserve"/*nonNLS*/;
	public static final String OPTIMIZE_OUT = "optimize out"/*nonNLS*/;
	public static final String VERSION_1_1 = "1.1"/*nonNLS*/;
	public static final String VERSION_1_2 = "1.2"/*nonNLS*/;
	public static final String ERROR = "error"/*nonNLS*/;
	public static final String WARNING = "warning"/*nonNLS*/;
	public static final String IGNORE = "ignore"/*nonNLS*/;
	public static final String COMPUTE = "compute"/*nonNLS*/;
	
	private static Hashtable ConfigurableOptions;
	private static Hashtable Variables = new Hashtable(5);
		// possible values are WARNING or IGNORE (default is IGNORE)

	public static final String COMPILER_PB_NON_EXTERNALIZED_STRING_LITERAL = PLUGIN_ID + ".compiler.problem.nonExternalizedStringLiteral"/*nonNLS*/;

/**
 * Creates the Java core plug-in.
 */
public JavaCore(IPluginDescriptor pluginDescriptor) {
	super(pluginDescriptor);
	JAVA_CORE_PLUGIN = this;
}
/**
 * Adds the given listener for changes to Java elements.
 * Has no effect if an identical listener is already registered.
 *
 * @param listener the listener
 */
public static void addElementChangedListener(IElementChangedListener listener) {
	JavaModelManager.getJavaModelManager().addElementChangedListener(listener);
}
/**
 * Configures the given marker attribute map for the given Java element.
 * Used for markers which denote a Java element rather than a resource.
 *
 * @param attributes the mutable marker attribute map (key type: <code>String</code>,
 *   value type: <code>String</code>)
 * @param element the Java element for which the marker needs to be configured
 */
public static void addJavaElementMarkerAttributes(Map attributes, IJavaElement element) {
	if (element instanceof IMember) 
		element= ((IMember) element).getClassFile();
	if (attributes != null && element != null)
		attributes.put(ATT_HANDLE_ID, element.getHandleIdentifier());
}
/**
 * Configures the given marker for the given Java element.
 * Used for markers which denote a Java element rather than a resource.
 *
 * @param marker the marker to be configured
 * @param element the Java element for which the marker needs to be configured
 * @exception CoreException if the <code>IMarker.setAttribute</code> on the marker fails
 */
public void configureJavaElementMarker(IMarker marker, IJavaElement element) throws CoreException {
	if (element instanceof IMember)
		element= ((IMember)element).getClassFile();
	if (marker != null && element != null)
		marker.setAttribute(ATT_HANDLE_ID, element.getHandleIdentifier());
}
/**
 * Returns the Java model element corresponding to the given handle identifier
 * generated by <code>IJavaElement.getHandleIdentifier()</code>, or
 * <code>null</code> if unable to create the associated element.
 */
public static IJavaElement create(String handleIdentifier) {
	if (handleIdentifier == null) {
		return null;
	}
	try {
		return JavaModelManager.getJavaModelManager().getHandleFromMemento(handleIdentifier);
	} catch (JavaModelException e) {
		return null;
	}
}
/**
 * Returns the Java element corresponding to the given file, or
 * <code>null</code> if unable to associate the given file
 * with a Java element.
 *
 * <p>The file must be one of:<ul>
 *	<li>a <code>.java</code> file - the element returned is the corresponding <code>ICompilationUnit</code></li>
 *	<li>a <code>.class</code> file - the element returned is the corresponding <code>IClassFile</code></li>
 *	<li>a <code>.jar</code> file - the element returned is the corresponding <code>IPackageFragmentRoot</code></li>
 *	</ul>
 * <p>
 * Creating a Java element has the side effect of creating and opening all of the
 * element's parents if they are not yet open.
 */
public static IJavaElement create(IFile file) {
	if (file == null) {
		return null;
	}
	String extension= file.getProjectRelativePath().getFileExtension();
	if (extension != null) {
		extension= extension.toLowerCase();
		if (extension.equals("java"/*nonNLS*/)) {
			return createCompilationUnitFrom(file);
		} else if (extension.equals("class"/*nonNLS*/)) {
			return createClassFileFrom(file);
		} else if (extension.equals("jar"/*nonNLS*/) || extension.equals("zip"/*nonNLS*/)) {
			return createJarPackageFragmentRootFrom(file);
		}
	}	
	return null;	
}
/**
 * Returns the package fragment or package fragment root corresponding to the given folder, or
 * <code>null</code> if unable to associate the given folder with a Java element.
 * <p>
 * Note that a package fragment root is returned rather than a default package.
 * <p>
 * Creating a Java element has the side effect of creating and opening all of the
 * element's parents if they are not yet open.
 */
public static IJavaElement create(IFolder folder) {
	if (folder == null) {
		return null;
	}
	if (folder.getName().indexOf('.') < 0) {
		JavaProject project = (JavaProject) create(folder.getProject());
		if (project == null) return null;
		IJavaElement element = determineIfOnClasspath(folder, project);	
		try {
			IPath outputLocation = project.getOutputLocation();
			if (outputLocation == null) return null;
			if (outputLocation.isPrefixOf(folder.getFullPath())) {
				if (project.getClasspathEntryFor(outputLocation) != null) {
					// if the output location is the same as an input location, return the element
					return element;
				} else {
					// otherwise, do not create elements for folders in the output location
					return null;
				}
			} else {
				return element;
			}
		} catch (JavaModelException e) {
			return null;
		}
	}
	return null;			
}
/**
 * Returns the Java project corresponding to the given project, or
 * <code>null</code> if unable to associate the given project
 * with a Java project.
 * <p>
 * Creating a Java Project has the side effect of creating and opening all of the
 * project's parents if they are not yet open.
 */
public static IJavaProject create(IProject project) {
	if (project == null) {
		return null;
	}
	JavaModel javaModel= JavaModelManager.getJavaModel(project.getWorkspace());
	return javaModel.getJavaProject(project);
}
/**
 * Returns the Java element corresponding to the given resource, or
 * <code>null</code> if unable to associate the given resource
 * with a Java element.
 * <p>
 * The resource must be one of:<ul>
 *	<li>a project - the element returned is the corresponding <code>IJavaProject</code></li>
 *	<li>a <code>.java</code> file - the element returned is the corresponding <code>ICompilationUnit</code></li>
 *	<li>a <code>.class</code> file - the element returned is the corresponding <code>IClassFile</code></li>
 *	<li>a <code>.jar</code> file - the element returned is the corresponding <code>IPackageFragmentRoot</code></li>
 *  <li>a folder - the element returned is the corresponding <code>IPackageFragmentRoot</code>
 *			or <code>IPackageFragment</code></li>
 *  <li>the workspace root resource - the element returned is the <code>IJavaModel</code></li>
 *	</ul>
 * <p>
 * Creating a Java element has the side effect of creating and opening all of the
 * element's parents if they are not yet open.
 */
public static IJavaElement create(IResource resource) {
	if (resource == null) {
		return null;
	}
	int type= resource.getType();
	switch (type) {
		case IResource.PROJECT:
			return create((IProject)resource);
		case IResource.FILE:
			return create((IFile)resource);	
		case IResource.FOLDER:
			return create((IFolder)resource);		
		case IResource.ROOT:
			return create((IWorkspaceRoot)resource);
		default:
			return null;
	}
}
/**
 * Returns the Java model.
 */
public static IJavaModel create(IWorkspaceRoot root) {
	if (root == null) {
		return null;
	}
	return JavaModelManager.getJavaModel(root.getWorkspace());
}
/**
 * Creates and returns a class file element for
 * the given <code>.class</code> file. Returns <code>null</code> if unable
 * to recognize the class file.
 */
public static IClassFile createClassFileFrom(IFile file) {
	IJavaProject project = (IJavaProject) create(file.getProject());
	IPackageFragment pkg = (IPackageFragment) determineIfOnClasspath(file, project);
	if (pkg == null) {
		// fix for 1FVS7WE
		// not on classpath - make the root its folder, and a default package
		IPackageFragmentRoot root= project.getPackageFragmentRoot(file.getParent());
		pkg= root.getPackageFragment(IPackageFragment.DEFAULT_PACKAGE_NAME);
	}
	return pkg.getClassFile(file.getName());
}
/**
 * Creates and returns a compilation unit element for
 * the given <code>.java</code> file. Returns <code>null</code> if unable
 * to recognize the compilation unit.
 */
public static ICompilationUnit createCompilationUnitFrom(IFile file) {
	IProject fileProject = file.getProject();
	IJavaProject project = (IJavaProject) create(fileProject);
	IPackageFragment pkg= (IPackageFragment)determineIfOnClasspath(file, project);
	if (pkg == null) {
		// fix for 1FVS7WE
		// not on classpath - make the root its folder, and a default package
		IPackageFragmentRoot root= project.getPackageFragmentRoot(file.getParent());
		pkg= root.getPackageFragment(IPackageFragment.DEFAULT_PACKAGE_NAME);
	} 
	return pkg.getCompilationUnit(file.getName());
}
/**
 * Creates and returns a handle for the given JAR file.
 * The Java model associated with the JAR's project may be
 * created as a side effect. 
 * Returns <code>null</code> if unable to create a JAR package fragment root.
 * (for example, if the JAR file represents a non-Java resource)
 */
public static IPackageFragmentRoot createJarPackageFragmentRootFrom(IFile file) {
	IJavaProject project= (IJavaProject)create(file.getProject());

	// Create a jar package fragment root only if on the classpath
	IPath resourcePath = file.getFullPath();
	try {
		IClasspathEntry[] entries = project.getResolvedClasspath(true);
		for (int i = 0, length = entries.length; i < length; i++) {
			IClasspathEntry entry = entries[i];
			IPath rootPath = entry.getPath();
			if (rootPath.equals(resourcePath)) {
				return project.getPackageFragmentRoot(file);
			}
		}
	} catch (JavaModelException e) {
	}
	return null;
}
/**
 * Returns the package fragment root represented by the resource, or
 * the package fragment the given resource is located in, or <code>null</code>
 * if the given resource is not on the classpath of the given project.
 */
private static IJavaElement determineIfOnClasspath(IResource resource, IJavaProject project) {
	IPath resourcePath = resource.getFullPath();
	try {
		IClasspathEntry[] entries = project.getResolvedClasspath(true);
		for (int i = 0; i < entries.length; i++) {
			IClasspathEntry entry = entries[i];
			IPath rootPath = entry.getPath();
			if (rootPath.equals(resourcePath)) {
				return project.getPackageFragmentRoot(resource);
			} else
				if (rootPath.isPrefixOf(resourcePath)) {
					IPackageFragmentRoot root = ((JavaProject)project).getPackageFragmentRoot(rootPath);
					IPath pkgPath = resourcePath.removeFirstSegments(rootPath.segmentCount());
					if (resource.getType() == IResource.FILE) {
						// if the resource is a file, then remove the last segment which
						// is the file name in the package
						pkgPath= pkgPath.removeLastSegments(1);
					}
					StringBuffer pkgName = new StringBuffer(IPackageFragment.DEFAULT_PACKAGE_NAME);
					for (int j = 0, max = pkgPath.segmentCount(); j < max; j++) {
						String segment = pkgPath.segment(j);
						if (segment.indexOf('.') >= 0) {
							return null;
						}
						pkgName.append(segment);
						if (j < pkgPath.segmentCount() - 1) {
							pkgName.append("."/*nonNLS*/);
						}
					}
					return root.getPackageFragment(pkgName.toString());
				}
		}
	} catch (JavaModelException npe) {
		return null;
	}
	return null;
}
/**
 * Returns the path held in the given classpath variable.
 * Returns <node>null</code> if unable to bind.
 * <p>
 * Classpath variable values are persisted locally to the workspace, and 
 * are preserved from session to session.
 * <p>
 *
 * @param variableName the name of the classpath variable
 * @return the path, or <code>null</code> if none 
 * @see #setClasspathVariable
 */
public static IPath getClasspathVariable(String variableName) {
	return (IPath)Variables.get(variableName);
}
/**
 * Returns the names of all known classpath variables.
 * <p>
 * Classpath variable values are persisted locally to the workspace, and 
 * are preserved from session to session.
 * <p>
 *
 * @return the list of classpath variable names
 * @see #setClasspathVariable
 */
public static String[] getClasspathVariableNames() {
	int length = Variables.size();
	String[] result = new String[length];
	Enumeration vars = Variables.keys();
	int index = 0;
	while (vars.hasMoreElements()){
		result[index++] = (String)vars.nextElement();
	}
	return result;
}
/**
 * Answers a set of configurable options with their default values.
 * These options allow to configure the behavior of the underlying components.
 * 
 * Recognized options are listed below, optionName = possibleValue1 / possibleValue2
 * where [] are enclosing the default value of the corresponding option.
 *
 * Note: more options might be added in further releases.
 *
 * RECOGNIZED OPTIONS:
 *
 *	COMPILER_LOCAL_VARIABLE_ATTR = [GENERATE] | DO_NOT_GENERATE
 *  	When generated, this attribute will enable local variable names to be displayed 
 * 		in debugger, only in place where variables are definitely assigned 
 *		(.class file is then bigger)
 *
 *  COMPILER_LINE_NUMBER_ATTR = [GENERATE] | DO_NOT_GENERATE 
 *		When generated, this attribute will enable source code highlighting in debugger 
 *		(.class file is then bigger).
 *		
 *  COMPILER_SOURCE_FILE_ATTR = [GENERATE] | DO_NOT_GENERATE
 *		When generated, this attribute will enable the debugger to present the 
 *		corresponding source code.
 *
 *  COMPILER_CODEGEN_UNUSED_LOCAL = [PRESERVE] | OPTIMIZE_OUT
 *		Unless requested to preserve unused local variables (i.e. never read), the 
 *		compiler will optimize them out, potentially altering debugging
 * 
 *  COMPILER_CODEGEN_TARGET_PLATFORM = [VERSION_1_1] | VERSION_1_2
 * 		Generate .class files either backward compatible with JVM 1.1 or only executable 
 *		on JVM 1.2 and later
 *
 *	COMPILER_PB_UNREACHABLE_CODE = [ERROR] | WARNING
 *		Unreachable code can either be reported as an error or a warning
 *
 *	COMPILER_PB_INVALID_IMPORT = [ERROR] | WARNING
 *		An import statement that cannot be resolved might either be reported 
 *		either as an error or as a warning
 *
 *	COMPILER_PB_OVERRIDING_PACKAGE_DEFAULT_METHOD = [WARNING] | IGNORE
 *		A package default method is not visible in a different package, and thus 
 *		cannot be overriden. When enabling this option, the compiler will signal 
 *		such scenarii.
 *
 *  COMPILER_PB_METHOD_WITH_CONSTRUCTOR_NAME = [WARNING] | IGNORE
 * 		Naming a method with a constructor name is generally considered poor 
 *		style programming. When enabling this option, the compiler will signal such 
 *		scenarii
 *
 *  COMPILER_PB_DEPRECATION = [WARNING] | IGNORE
 *		When enabled, the compiler will signal use of deprecated API.
 *
 *	COMPILER_PB_HIDDEN_CATCH_BLOCK = [WARNING] | IGNORE
 *		Locally to a try statement, some catch blocks may hide others 
 *		(e.g. 	try {	throw new java.io.CharConversionException();
 *				} catch (java.io.CharConversionException e) {
 *				} catch (java.io.IOException e) {}). 
 *		When enabling this option, the compiler will issue a warning for hidden catch 
 *		blocks corresponding to checked exceptions
 *
 *  COMPILER_PB_UNUSED_LOCAL = WARNING | [IGNORE]
 * 		When enabled, the compiler will issue a warning for unused local variables 
 *		(i.e. variables never read from)
 *
 *	COMPILER_PB_UNUSED_PARAMETER = WARNING | [IGNORE]
 *		When enabled, the compiler will issue a warning for unused method parameters 
 *		(i.e. parameters never read from)
 *
 *	COMPILER_PB_SYNTHETIC_ACCESS_EMULATION = WARNING | [IGNORE]
 *		When enabled, the compiler will issue a warning whenever it emulates access 
 *		to a non-accessible member of an enclosing type
 *
 *	CORE_JAVA_BUILD_ORDER = [COMPUTE] | IGNORE
 *		When enabled, the build order is automatically reflecting the classpath on each
 *		classpath change action. It can still be modified manually afterwards.
 */
 
public static Hashtable getDefaultOptions(){

	Hashtable defaultOptions = new Hashtable(10);

	// Compiler settings
	defaultOptions.put(COMPILER_LOCAL_VARIABLE_ATTR, 					GENERATE);
	defaultOptions.put(COMPILER_LINE_NUMBER_ATTR, 						GENERATE);
	defaultOptions.put(COMPILER_SOURCE_FILE_ATTR,						GENERATE);
	defaultOptions.put(COMPILER_CODEGEN_UNUSED_LOCAL,					PRESERVE);
	defaultOptions.put(COMPILER_CODEGEN_TARGET_PLATFORM,				VERSION_1_1);
	defaultOptions.put(COMPILER_PB_UNREACHABLE_CODE,					ERROR);
	defaultOptions.put(COMPILER_PB_INVALID_IMPORT,						ERROR);
	defaultOptions.put(COMPILER_PB_OVERRIDING_PACKAGE_DEFAULT_METHOD, 	WARNING);
	defaultOptions.put(COMPILER_PB_METHOD_WITH_CONSTRUCTOR_NAME,		WARNING);
	defaultOptions.put(COMPILER_PB_DEPRECATION,							WARNING);
	defaultOptions.put(COMPILER_PB_HIDDEN_CATCH_BLOCK,					WARNING);
	defaultOptions.put(COMPILER_PB_UNUSED_LOCAL,						IGNORE);
	defaultOptions.put(COMPILER_PB_UNUSED_PARAMETER,					IGNORE);
	defaultOptions.put(COMPILER_PB_SYNTHETIC_ACCESS_EMULATION,			IGNORE);
	defaultOptions.put(COMPILER_PB_NON_EXTERNALIZED_STRING_LITERAL,		IGNORE);
	
	// JavaCore settings
	defaultOptions.put(CORE_JAVA_BUILD_ORDER,							IGNORE);

	return defaultOptions;
}
/**
 * Returns the single instance of the Java core plug-in runtime class.
 * Equivalent to <code>(JavaCore) getPlugin()</code>.
 */
public static JavaCore getJavaCore() {
	return (JavaCore) getPlugin();
}
/**
 * Returns the <code>IJavaProject</code> associated with the
 * given <code>IProject</code>, or <code>null</code> if the
 * project does not have a Java nature.
 */
private IJavaProject getJavaProject(IProject project) {
	try {
		if (project.hasNature(NATURE_ID)) {
			JavaModel model= JavaModelManager.getJavaModel(project.getWorkspace());
			if (model != null) {
				return model.getJavaProject(project);
			}
		}
	} catch (CoreException e) {
	}
	return null;
}
/**
 * Answers a copy of the current set of configurable options supported by the Java core.
 * These options allow to configure the behavior of the underlying components.
 *
 * Changes on the set of options are not committed until invoking <code>JavaCore.setOptions</code>
 *
 * For a list of recognized options, refer to <code>JavaCore.getDefaultOptions</code>
 */
public static Hashtable getOptions(){

	if (ConfigurableOptions == null) return ConfigurableOptions = getDefaultOptions();
	return (Hashtable)ConfigurableOptions.clone();
}
/**
 * Returns the single instance of the Java core plug-in runtime class.
 */
public static Plugin getPlugin() {
	return JAVA_CORE_PLUGIN;
}
/**
 * This is a helper method which returns the resolved classpath entry denoted 
 * by a given entry (if it is a variable entry). It is obtained by resolving the variable 
 * reference in the first segment. Returns <node>null</code> if unable to resolve using 
 * the following algorithm:
 * <ul>
 * <li> if variable segment cannot be resolved, returns <code>null</code></li>
 * <li> finds a project, JAR or binary folder in the workspace at the resolved path location</li>
 * <li> if none finds an external JAR file or folder outside the workspace at the resolved path location </li>
 * <li> if none returns <code>null</code></li>
 * </ul>
 * <p>
 * Variable source attachment path and root path are also resolved and recorded in the resulting classpath entry.
 * <p>
 * @return the resolved library or project classpath entry, or <code>null</code>
 *   if the given variable entry could not be resolved to a valid classpath entry
 */
public static IClasspathEntry getResolvedClasspathEntry(IClasspathEntry entry) {

	if (entry.getEntryKind() != IClasspathEntry.CPE_VARIABLE) return entry;

	IWorkspaceRoot workspaceRoot = ResourcesPlugin.getWorkspace().getRoot();
	IPath resolvedPath = JavaCore.getResolvedVariablePath(entry.getPath());
	if (resolvedPath == null) return null;

	Object target = JavaModel.getTarget(workspaceRoot, resolvedPath, false);
	if (target == null) return null;

	// inside the workspace
	if (target instanceof IResource){	
		IResource resolvedResource = (IResource) target;
		if (resolvedResource != null){
			switch(resolvedResource.getType()){
				case IResource.PROJECT :
					return JavaCore.newProjectEntry(resolvedPath); // internal project
				case IResource.FILE :
					String extension = resolvedResource.getFileExtension();
					if ("jar"/*nonNLS*/.equalsIgnoreCase(extension) || "zip"/*nonNLS*/.equalsIgnoreCase(extension)){ // internal binary archive
						return JavaCore.newLibraryEntry( 
								resolvedPath,
								getResolvedVariablePath(entry.getSourceAttachmentPath()),
								getResolvedVariablePath(entry.getSourceAttachmentRootPath())); 
					}
					break;
				case IResource.FOLDER :	// internal binary folder
					return JavaCore.newLibraryEntry( 
							resolvedPath,
							getResolvedVariablePath(entry.getSourceAttachmentPath()),
							getResolvedVariablePath(entry.getSourceAttachmentRootPath())); 
			}
		}
	}
	// outside the workspace
	if (target instanceof File){
		File externalFile = (File) target;
		if (externalFile.isFile()){
			String fileName = externalFile.getName().toLowerCase();
			if (fileName.endsWith(".jar"/*nonNLS*/) || fileName.endsWith(".zip"/*nonNLS*/)){ // external binary archive
				return JavaCore.newLibraryEntry( 
						resolvedPath,
						getResolvedVariablePath(entry.getSourceAttachmentPath()),
						getResolvedVariablePath(entry.getSourceAttachmentRootPath())); 
			}
		} else { // external binary folder
			return JavaCore.newLibraryEntry( 
						resolvedPath,
						getResolvedVariablePath(entry.getSourceAttachmentPath()),
						getResolvedVariablePath(entry.getSourceAttachmentRootPath())); 
		}
	}
	return null;
}
/**
 * Resolve a variable path (helper method)
 */
public static IPath getResolvedVariablePath(IPath variablePath) {

	if (variablePath == null) return null;
	int count = variablePath.segmentCount();
	if (count == 0) return null;

	// lookup variable	
	String variableName = variablePath.segment(0);
	IPath resolvedPath = JavaCore.getClasspathVariable(variableName);
	if (resolvedPath == null || resolvedPath.isEmpty()) return null;

	// append path suffix
	if (count > 1){
		resolvedPath = resolvedPath.append(variablePath.removeFirstSegments(1));
	}
	return resolvedPath;
}
/**
 * Returns whether the given marker references the given Java element.
 * Used for markers which denote a Java element rather than a resource.
 *
 * @param element the element
 * @param marker the marker
 * @return <code>true</code> if the marker references the element
 * @exception CoreException if the <code>IMarker.getAttribute</code> on the marker fails 	 
 */
 public static boolean isReferencedBy(IJavaElement element, IMarker marker) throws CoreException {
 	if (element instanceof IMember)
 		element= ((IMember)element).getClassFile();
 	return (element != null 
	 		&& marker != null
	 		&& element.getHandleIdentifier().equals(marker.getAttribute(ATT_HANDLE_ID)));
}
/**
 * Returns whether the given marker delta references the given Java element.
 * Used for markers deltas which denote a Java element rather than a resource.
 *
 * @param element the element
 * @param markerDelta the marker delta
 * @return <code>true</code> if the marker delta references the element
 * @exception CoreException if the  <code>IMarkerDelta.getAttribute</code> on the marker delta fails 	 
 */
public static boolean isReferencedBy(IJavaElement element, IMarkerDelta markerDelta) throws CoreException {
	if (element instanceof IMember)	element= ((IMember) element).getClassFile();
	return element != null 
			&& markerDelta != null 
			&& element.getHandleIdentifier().equals(markerDelta.getAttribute(ATT_HANDLE_ID));
}
/**
 * Creates and returns a new classpath entry of kind <code>CPE_LIBRARY</code> for the JAR or folder
 * identified by the given absolute path. This specifies that all package fragments within the root 
 * will have children of type <code>IClassFile</code>.
 * <p>
 * A library entry is used to denote a prerequisite JAR or root folder containing binaries.
 * The target JAR or folder can either be defined internally to the workspace (absolute path relative
 * to the workspace root) or externally to the workspace (absolute path in the file system).
 *
 * e.g. Here are some examples of binary path usage<ul>
 *	<li><code> "c:/jdk1.2.2/jre/lib/rt.jar" </code> - reference to an external JAR</li>
 *	<li><code> "/Project/someLib.jar" </code> - reference to an internal JAR </li>
 *	<li><code> "c:/classes/" </code> - reference to an external binary folder</li>
 * </ul>
 * Note that this operation does not attempt to validate or access the 
 * resources at the given paths.
 * <p>
 * @param path the absolute path of the binary archive
 * @param sourceAttachmentPath the absolute path of the corresponding source archive, 
 *    or <code>null</code> if none
 * @param sourceAttachmentRootPath the location of the root within the source archive
 *    or <code>null</code> if <code>archivePath</code> is also <code>null</code>
 */ 

public static IClasspathEntry newLibraryEntry(IPath path, IPath sourceAttachmentPath, IPath sourceAttachmentRootPath) {
	Assert.isTrue(path.isAbsolute(), Util.bind("classpath.needAbsolutePath"/*nonNLS*/));
	return new ClasspathEntry(
			IPackageFragmentRoot.K_BINARY, 
			IClasspathEntry.CPE_LIBRARY, 
			JavaProject.canonicalizedPath(path),
			sourceAttachmentPath,
			sourceAttachmentRootPath);
}
/**
 * Creates and returns a new classpath entry of kind <code>CPE_PROJECT</code>
 * for the project identified by the given absolute path.
 * <p>
 * A project entry is used to denote a prerequisite project on a classpath.
 * The referenced project will be contributed as a whole, either as sources (in the Java Model, it
 * contributes all its package fragment roots) or as binaries (when building, it contributes its 
 * whole output location).
 * <p>
 * A project reference allows to indirect through another project, independently from its internal layout. 
 * <p>
 * The prerequisite project is referred to using an absolute path relative to the workspace root.
 */
public static IClasspathEntry newProjectEntry(IPath path){
	Assert.isTrue(path.isAbsolute(), Util.bind("classpath.needAbsolutePath"/*nonNLS*/));
	return new ClasspathEntry(IPackageFragmentRoot.K_SOURCE, IClasspathEntry.CPE_PROJECT, path, null, null);
}
/**
 * Returns a new empty region.
 */
public static IRegion newRegion() {
	return new Region();
}
/**
 * Creates and returns a new classpath entry of kind <code>CPE_SOURCE</code> for the project's source folder 
 * identified by the given absolute path. This specifies that all package fragments within the root will 
 * have children of type <code>ICompilationUnit</code>.
 * <p>
 * The source folder is referred to using an absolute path relative to the workspace root, e.g. <code>"/Project/src"</code>.
 * <p>
 * A source entry is used to setup the internal source layout of a project, and cannot be used out of the
 * context of the containing project (a source entry "Proj1/src" cannot be used on the classpath of Proj2).
 */ 
public static IClasspathEntry newSourceEntry(IPath path){
	Assert.isTrue(path.isAbsolute(), Util.bind("classpath.needAbsolutePath"/*nonNLS*/));
	return new ClasspathEntry(IPackageFragmentRoot.K_SOURCE, IClasspathEntry.CPE_SOURCE, path, null, null);
}
/**
 * Creates and returns a new classpath entry of kind <code>CPE_VARIABLE</code>
 * for the given path. The first segment of the the path is the name of a classpath variable.
 * The trailing segments of the path will be appended to resolved variable path.
 * <p>
 * A variable entry allows to express indirect references on a classpath to other projects or libraries,
 * depending on what the classpath variable is referring.
 * <p>
 * e.g. Here are some examples of variable path usage<ul>
 * <li><"JDTCORE" where variable <code>JDTCORE</code> is 
 *		bound to "c:/jars/jdtcore.jar". The resoved classpath entry is denoting the library "c:\jars\jdtcore.jar"</li>
 * <li> "JDTCORE" where variable <code>JDTCORE</code> is 
 *		bound to "/Project_JDTCORE". The resoved classpath entry is denoting the project "/Project_JDTCORE"</li>
 * <li> "PLUGINS/com.example/example.jar" where variable <code>PLUGINS</code>
 *      is bound to "c:/eclipse/plugins". The resolved classpath entry is denoting the library "c:/eclipse/plugins/com.example/example.jar"</li>
 * </ul>
 * <p>
 * Note that this operation does not attempt to validate classpath variables
 * or access the resources at the given paths.
 * <p>
 * @param variablePath the path of the binary archive; first segment is the
 *   name of a classpath variable
 * @param variableSourceAttachmentPath the path of the corresponding source archive, 
 *    or <code>null</code> if none; if present, the first segment is the
 *    name of a classpath variable (not necessarily the same variable
 *    as the one that begins <code>variablePath</code>)
 * @param sourceAttachmentRootPath the location of the root within the source archive
 *    or <code>null</code> if <code>archivePath</code> is also <code>null</code>
 */
public static IClasspathEntry newVariableEntry(IPath variablePath, IPath variableSourceAttachmentPath, IPath sourceAttachmentRootPath){
	Assert.isTrue(variablePath != null && variablePath.segmentCount() >= 1, Util.bind("classpath.illegalVariablePath"/*nonNLS*/));
	return new ClasspathEntry(
					IPackageFragmentRoot.K_SOURCE, 
					IClasspathEntry.CPE_VARIABLE, 
					variablePath,
					variableSourceAttachmentPath,
					sourceAttachmentRootPath);
}
/**
 * Removed the given classpath variable. Does nothing if no value was
 * set for this classpath variable.
 * <p>
 * This functionality cannot be used while the resource tree is locked.
 * <p>
 * Classpath variable values are persisted locally to the workspace, and 
 * are preserved from session to session.
 * <p>
 *
 * @param variableName the name of the classpath variable
 * @see #setClasspathVariable
 *
 * @deprecated - use version with extra IProgressMonitor
 */
public static void removeClasspathVariable(String variableName) {

	removeClasspathVariable(variableName, null);
}
/**
 * Removed the given classpath variable. Does nothing if no value was
 * set for this classpath variable.
 * <p>
 * This functionality cannot be used while the resource tree is locked.
 * <p>
 * Classpath variable values are persisted locally to the workspace, and 
 * are preserved from session to session.
 * <p>
 *
 * @param variableName the name of the classpath variable
 * @param monitor the progress monitor to report progress
 * @see #setClasspathVariable
 */
public static void removeClasspathVariable(String variableName, IProgressMonitor monitor) {

	try {
		updateVariableValue(variableName, null, monitor);
	} catch(JavaModelException e){
	}
}
/**
 * Removes the given element changed listener.
 * Has no affect if an identical listener is not registered.
 *
 * @param listener the listener
 */
public static void removeElementChangedListener(IElementChangedListener listener) {
	JavaModelManager.getJavaModelManager().removeElementChangedListener(listener);
}
/**
 * Sets the value of the given classpath variable.
 * The path must have at least one segment.
 * <p>
 * This functionality cannot be used while the resource tree is locked.
 * <p>
 * Classpath variable values are persisted locally to the workspace, and 
 * are preserved from session to session.
 * <p>
 *
 * @param variableName the name of the classpath variable
 * @param path the path
 * @see #getClasspathVariable
 *
 * @deprecated - use API with IProgressMonitor
 */
public static void setClasspathVariable(String variableName, IPath path) throws JavaModelException {

	setClasspathVariable(variableName, path, null);
}
/**
 * Sets the value of the given classpath variable.
 * The path must have at least one segment.
 * <p>
 * This functionality cannot be used while the resource tree is locked.
 * <p>
 * Classpath variable values are persisted locally to the workspace, and 
 * are preserved from session to session.
 * <p>
 *
 * @param variableName the name of the classpath variable
 * @param path the path
 * @param monitor a monitor to report progress
 * @see #getClasspathVariable
 */
public static void setClasspathVariable(String variableName, IPath path, IProgressMonitor monitor) throws JavaModelException {

	Assert.isTrue(path != null, Util.bind("classpath.nullVariablePath"/*nonNLS*/));
	updateVariableValue(variableName, path, monitor);
}
/* (non-Javadoc)
 * Method declared on IExecutableExtension.
 * Record any necessary initialization data from the plugin.
 */
public void setInitializationData(IConfigurationElement cfig, String propertyName, Object data) throws CoreException {}
/**
 * Set current set of configurable options supported by the Java core.
 * These options allow to configure the behavior of the underlying components.
 * 
 * For a list of recognized options, refer to <code>JavaCore.getDefaultOptions</code>
 */
public static void setOptions(Hashtable configurableOptions){
	ConfigurableOptions = (Hashtable) configurableOptions.clone();
}
/**
 * Shutdown the JavaCore plugin
 * <p>
 * De-registers the JavaModelManager as a resource changed listener and save participant.
 * <p>
 * @see Plugin#shutdown
 */
public void shutdown() {

	IWorkspace workspace = ResourcesPlugin.getWorkspace();
	workspace.removeResourceChangeListener(JavaModelManager.getJavaModelManager());
	workspace.removeSaveParticipant(this);

	((JavaModelManager) JavaModelManager.getJavaModelManager()).shutdown();
}
/**
 * Initiate the background indexing process.
 * This should be deferred after the plugin activation.
 */
private void startIndexing() {

	JavaModelManager manager = (JavaModelManager) JavaModelManager.getJavaModelManager();
	IndexManager indexManager = manager.getIndexManager(); 
	if (indexManager != null) indexManager.reset();
	/*	
		// if there is a desktop defer the start of the indexing by posting a runnable
		if (getDesktopPlugin() != null) {
			IDesktop desktop= getDesktop();
			ApplicationWindow window= (ApplicationWindow) desktop.getActiveDesktopWindow();
			Display display= null;
			if (window != null)
				display= window.getDisplay();
			if (display != null) {
				display.asyncExec(start);
				return;
			}
		}
	*/		
}
/**
 * Startup of the JavaCore plugin
 * <p>
 * Registers the JavaModelManager as a resource changed listener and save participant.
 * Starts the background indexing, and restore saved classpath variable values.
 * <p>
 * @see Plugin#startup
 */
public void startup() {
		JavaModelManager manager = JavaModelManager.getJavaModelManager();
	try {
		IWorkspace workspace = ResourcesPlugin.getWorkspace();
		IndexManager indexManager = manager.getIndexManager();
		if (indexManager != null) {
			// need to initialize workbench now since a query may be done before indexing starts
			indexManager.workspace = workspace;
		}
		workspace.addResourceChangeListener(
			manager, 
			IResourceChangeEvent.PRE_AUTO_BUILD | IResourceChangeEvent.POST_CHANGE 
				| IResourceChangeEvent.PRE_DELETE | IResourceChangeEvent.PRE_CLOSE);
		
		startIndexing();

		workspace.addSaveParticipant(this, manager);
		manager.loadVariables();
	} catch(CoreException e) {
	} catch(RuntimeException e){
		manager.shutdown();
		throw e;
	}
}
/**
 * Internal updating of a variable value (null path meaning removal).
 */
private static void updateVariableValue(String variableName, IPath path, IProgressMonitor monitor) throws JavaModelException {

	// gather classpath information for updating
	Hashtable affectedProjects = new Hashtable(5);
	JavaModelManager manager = JavaModelManager.getJavaModelManager();
	try {
		IJavaModel model = manager.getJavaModel();
		if (model != null){
			IJavaProject[] projects = model.getJavaProjects();
			nextProject: for (int i = 0, max = projects.length; i < max; i++){
				IClasspathEntry[] entries = projects[i].getRawClasspath();
				for (int j = 0, cplength = entries.length; j < cplength; j++){
					IClasspathEntry oldEntry = entries[j];
					if (oldEntry.getEntryKind() == IClasspathEntry.CPE_VARIABLE){
						IPath sourcePath, sourceRootPath;
						if (oldEntry.getPath().segment(0).equals(variableName) 
								|| ((sourcePath = oldEntry.getSourceAttachmentPath()) != null && sourcePath.segment(0).equals(variableName))
								|| ((sourceRootPath = oldEntry.getSourceAttachmentRootPath()) != null && sourceRootPath.segment(0).equals(variableName))) {
							affectedProjects.put(projects[i], projects[i].getResolvedClasspath(true));
							continue nextProject;
						}
					}
				}
			}
		}
	} catch(JavaModelException e){
	}

	if (path == null){
		Variables.remove(variableName);
	} else {
		// new variable value is assigned
		Variables.put(variableName, path);
	}

	if (!affectedProjects.isEmpty()){
		boolean wasFiring = manager.isFiring();
		try {
			if (wasFiring) manager.stopDeltas();
			// propagate classpath change
			Enumeration projectsToUpdate = affectedProjects.keys();
			while (projectsToUpdate.hasMoreElements()){
				JavaProject project = (JavaProject)projectsToUpdate.nextElement();
				project.setRawClasspath(
					project.getRawClasspath(), 
					monitor, 
					project.getWorkspace().isAutoBuilding(), // force build if in auto build mode
					(IClasspathEntry[])affectedProjects.get(project));
			}
		} finally {
			manager.mergeDeltas();
			if (wasFiring){
				manager.startDeltas();
				manager.fire();
			}
		}
	}
}
}