/*******************************************************************************
* Copyright (c) 2003, 2011 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are 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:
* IBM Corporation - Initial API and implementation
*******************************************************************************/
package org.eclipse.wst.server.core.internal;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.core.expressions.*;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.wst.server.core.IModule;
import org.eclipse.wst.server.core.IModuleType;
import org.eclipse.wst.server.core.model.InternalInitializer;
import org.eclipse.wst.server.core.model.ModuleFactoryDelegate;
/**
*
*/
public class ModuleFactory implements IOrdered {
private IConfigurationElement element;
public ModuleFactoryDelegate delegate;
private List<IModuleType> moduleTypes;
private Expression fContextualLaunchExpr = null;
/**
* ModuleFactory constructor comment.
*
* @param element a configuration element
*/
public ModuleFactory(IConfigurationElement element) {
super();
this.element = element;
}
/**
* Returns the id of this factory.
*
* @return java.lang.String
*/
public String getId() {
return element.getAttribute("id");
}
/**
* Returns the index (ordering) of this task.
*
* @return int
*/
public int getOrder() {
try {
return Integer.parseInt(element.getAttribute("order"));
} catch (NumberFormatException e) {
return -1;
}
}
/**
* Return the supported module types.
*
* @return an array of module types
*/
public IModuleType[] getModuleTypes() {
if (moduleTypes == null)
moduleTypes = ServerPlugin.getModuleTypes(element.getChildren("moduleType"));
IModuleType[] mt = new IModuleType[moduleTypes.size()];
moduleTypes.toArray(mt);
return mt;
}
/**
* Returns true if this modules factory produces project modules.
*
* @return boolean
*/
public boolean isProjectModuleFactory() {
return "true".equalsIgnoreCase(element.getAttribute("projects"));
}
/*
* @see IModuleFactoryDelegate#getDelegate()
*/
public ModuleFactoryDelegate getDelegate(IProgressMonitor monitor) {
if (delegate == null) {
try {
long time = System.currentTimeMillis();
delegate = (ModuleFactoryDelegate) element.createExecutableExtension("class");
InternalInitializer.initializeModuleFactoryDelegate(delegate, this, monitor);
if (Trace.PERFORMANCE) {
Trace.trace(Trace.STRING_PERFORMANCE,
"ModuleFactory.getDelegate(): <" + (System.currentTimeMillis() - time) + "> " + getId());
}
} catch (Throwable t) {
if (Trace.SEVERE) {
Trace.trace(Trace.STRING_SEVERE, "Could not create delegate " + toString(), t);
}
}
}
return delegate;
}
/*
* @see ModuleFactoryDelegate#getModules()
*/
public IModule[] getModules() {
return getModules(null);
}
/*
* @see ModuleFactoryDelegate#getModules()
*/
public IModule[] getModules(IProgressMonitor monitor) {
try {
IModule[] modules = getDelegate(monitor).getModules();
if (hasInvalidModules(modules))
modules = filter(modules);
return modules;
} catch (Throwable t) {
if (Trace.SEVERE) {
Trace.trace(Trace.STRING_SEVERE, "Error calling delegate " + toString(), t);
}
return new IModule[0];
}
}
/*
* @see ModuleFactoryDelegate#getModules(IProject)
*/
public IModule[] getModules(IProject project, IProgressMonitor monitor) {
try {
IModule[] modules = getDelegate(monitor).getModules(project);
if (hasInvalidModules(modules))
modules = filter(modules);
return modules;
} catch (Throwable t) {
if (Trace.SEVERE) {
Trace.trace(Trace.STRING_SEVERE, "Error calling delegate " + toString(), t);
}
return new IModule[0];
}
}
/**
* Returns an expression that represents the enablement logic for the
* contextual project of this module factory <code>null</code> if none.
* @return an evaluatable expression or <code>null</code>
* @throws CoreException if the configuration element can't be
* converted. Reasons include: (a) no handler is available to
* cope with a certain configuration element or (b) the XML
* expression tree is malformed.
*/
protected Expression getContextualLaunchEnablementExpression() throws CoreException {
if (fContextualLaunchExpr == null) {
IConfigurationElement[] elements = element.getChildren(ExpressionTagNames.ENABLEMENT);
IConfigurationElement enablement = (elements != null && elements.length > 0) ? elements[0] : null;
if (enablement != null)
fContextualLaunchExpr = ExpressionConverter.getDefault().perform(enablement);
}
return fContextualLaunchExpr;
}
/**
* Evaluate the given expression within the given context and return
* the result. Returns <code>true</code> if result is either TRUE or NOT_LOADED.
* This allows optimistic inclusion before plugins are loaded.
* Returns <code>true</code> if exp is <code>null</code>.
*
* @param exp the enablement expression to evaluate or <code>null</code>
* @param context the context of the evaluation.
* @return the result of evaluating the expression
* @throws CoreException
*/
protected boolean evalEnablementExpression(IEvaluationContext context, Expression exp) throws CoreException {
// for compatibility with the current behaviour, if the exp == null we return true. Meaning that the factory doesn't
// implement an expression and should be enabled for all cases.
return (exp != null) ? ((exp.evaluate(context)) != EvaluationResult.FALSE) : true;
}
public boolean isEnabled(IProject project, IProgressMonitor monitor) {
try {
IEvaluationContext context = new EvaluationContext(null, project);
context.addVariable("project", project);
return evalEnablementExpression(context, getContextualLaunchEnablementExpression());
} catch (Throwable t) {
if (Trace.SEVERE) {
Trace.trace(Trace.STRING_SEVERE, "Error calling delegate " + toString(), t);
}
return false;
}
}
/*
* @see ModuleFactoryDelegate#findModule(String)
*/
public IModule findModule(String id, IProgressMonitor monitor) {
try {
IModule module = getDelegate(monitor).findModule(id);
if (module == null)
return null;
getModuleTypes();
if (!moduleTypes.contains(module.getModuleType()))
return null;
return module;
} catch (Throwable t) {
if (Trace.SEVERE) {
Trace.trace(Trace.STRING_SEVERE, "Error calling delegate " + toString(), t);
}
return null;
}
}
private boolean hasInvalidModules(IModule[] modules) {
if (modules == null)
return false;
getModuleTypes();
int size = modules.length;
for (int i = 0; i < size; i++) {
if (!moduleTypes.contains(modules[i].getModuleType()))
return true;
}
return false;
}
private IModule[] filter(IModule[] modules) {
if (modules == null)
return modules;
getModuleTypes();
List<IModule> list = new ArrayList<IModule>();
int size = modules.length;
for (int i = 0; i < size; i++) {
IModule m = modules[i];
if (moduleTypes.contains(m.getModuleType()))
list.add(m);
else if (Trace.WARNING) {
Trace.trace(Trace.STRING_WARNING, "Invalid module returned from factory, ignored: " + m);
}
}
IModule[] m = new IModule[list.size()];
list.toArray(m);
return m;
}
/**
* Return a string representation of this object.
*
* @return java.lang.String
*/
public String toString() {
return "ModuleFactory[" + getId() + "]";
}
}