Filter.java

/*******************************************************************************
 * Copyright (c) 2008, 2010 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:
 *     Serge Beauchamp (Freescale Semiconductor) - initial API and implementation
 *     IBM Corporation - ongoing implementation
 *******************************************************************************/
package org.eclipse.core.internal.resources;

import java.util.Iterator;
import java.util.LinkedList;
import org.eclipse.core.filesystem.IFileInfo;
import org.eclipse.core.internal.utils.Messages;
import org.eclipse.core.internal.utils.Policy;
import org.eclipse.core.resources.*;
import org.eclipse.core.resources.filtermatchers.AbstractFileInfoMatcher;
import org.eclipse.core.runtime.*;
import org.eclipse.osgi.util.NLS;

/**
 * Class that instantiate IResourceFilter's that are stored in the project description.
 */
public class Filter {

	FilterDescription description;

	IProject project;

	AbstractFileInfoMatcher provider= null;

	public Filter(IProject project, FilterDescription description) {
		this.description= description;
		this.project= project;
	}

	public boolean match(IContainer parent, IFileInfo fileInfo) throws CoreException {
		if (provider == null) {
			IFilterMatcherDescriptor filterDescriptor= project.getWorkspace().getFilterMatcherDescriptor(getId());
			if (filterDescriptor != null)
				provider= ((FilterDescriptor)filterDescriptor).createFilter();
			if (provider == null) {
				String message= NLS.bind(Messages.filters_missingFilterType, getId());
				throw new CoreException(new Status(IStatus.ERROR, ResourcesPlugin.PI_RESOURCES, Platform.PLUGIN_ERROR, message, new Error()));
			}
			try {
				provider.initialize(project, description.getFileInfoMatcherDescription().getArguments());
			} catch (CoreException e) {
				Policy.log(e.getStatus());
				provider= null;
			}
		}
		if (provider != null)
			return provider.matches(parent, fileInfo);
		return false;
	}

	public boolean isFirst() {
		IFilterMatcherDescriptor descriptor= project.getWorkspace().getFilterMatcherDescriptor(getId());
		if (descriptor != null)
			return descriptor.isFirstOrdering();
		return false;
	}

	public Object getArguments() {
		return description.getFileInfoMatcherDescription().getArguments();
	}

	public String getId() {
		return description.getFileInfoMatcherDescription().getId();
	}

	public int getType() {
		return description.getType();
	}

	public boolean isIncludeOnly() {
		return (getType() & IResourceFilterDescription.INCLUDE_ONLY) != 0;
	}

	public boolean appliesTo(IFileInfo info) {
		if (info.isDirectory())
			return (getType() & IResourceFilterDescription.FOLDERS) != 0;
		return (getType() & IResourceFilterDescription.FILES) != 0;
	}

	public static IFileInfo[] filter(IProject project, LinkedList/*Filter*/includeFilters, LinkedList/*Filter*/excludeFilters, IContainer parent, IFileInfo[] list) throws CoreException {
		IFileInfo[] result= filterIncludes(project, includeFilters, parent, list);
		return filterExcludes(project, excludeFilters, parent, result);
	}

	public static IFileInfo[] filterIncludes(IProject project, LinkedList/*Filter*/filters, IContainer parent, IFileInfo[] list) throws CoreException {
		if (filters.size() > 0) {
			IFileInfo[] result= new IFileInfo[list.length];
			int outputIndex= 0;

			for (int i= 0; i < list.length; i++) {
				IFileInfo info= list[i];
				Iterator objIt= filters.iterator();
				boolean filtersWereApplicable= false;
				while (objIt.hasNext()) {
					Filter filter= (Filter)objIt.next();
					if (filter.appliesTo(info)) {
						filtersWereApplicable= true;
						if (filter.match(parent, info)) {
							result[outputIndex++]= info;
							break;
						}
					}
				}
				if (!filtersWereApplicable)
					result[outputIndex++]= info;
			}
			if (outputIndex != result.length) {
				IFileInfo[] tmp= new IFileInfo[outputIndex];
				System.arraycopy(result, 0, tmp, 0, outputIndex);
				result= tmp;
			}
			return result;
		}
		return list;
	}

	public static IFileInfo[] filterExcludes(IProject project, LinkedList/*Filter*/filters, IContainer parent, IFileInfo[] list) throws CoreException {
		if (filters.size() > 0) {
			IFileInfo[] result= new IFileInfo[list.length];
			int outputIndex= 0;

			for (int i= 0; i < list.length; i++) {
				IFileInfo info= list[i];
				Iterator objIt= filters.iterator();
				boolean shouldBeExcluded= false;
				while (objIt.hasNext()) {
					Filter filter= (Filter)objIt.next();
					if (filter.appliesTo(info)) {
						if (filter.match(parent, info)) {
							shouldBeExcluded= true;
							break;
						}
					}
				}
				if (!shouldBeExcluded)
					result[outputIndex++]= info;
			}
			if (outputIndex != result.length) {
				IFileInfo[] tmp= new IFileInfo[outputIndex];
				System.arraycopy(result, 0, tmp, 0, outputIndex);
				result= tmp;
			}
			return result;
		}
		return list;
	}
}