/*******************************************************************************
* Copyright (c) 2000, 2009 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.cdt.internal.ui.filters;
import com.ibm.icu.text.Collator;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtensionRegistry;
import org.eclipse.core.runtime.ISafeRunnable;
import org.eclipse.core.runtime.Platform;
import org.eclipse.jface.util.SafeRunnable;
import org.eclipse.jface.viewers.ViewerFilter;
import org.eclipse.osgi.util.NLS;
import org.eclipse.cdt.ui.CUIPlugin;
/**
* Represents a custom filter which is provided by the
* "org.eclipse.jdt.ui.javaElementFilters" extension point.
*
* since 2.0
*/
public class FilterDescriptor implements Comparable<FilterDescriptor> {
private static String PATTERN_FILTER_ID_PREFIX= "_patternFilterId_"; //$NON-NLS-1$
private static final String EXTENSION_POINT_NAME= "CElementFilters"; //$NON-NLS-1$
private static final String FILTER_TAG= "filter"; //$NON-NLS-1$
private static final String PATTERN_ATTRIBUTE= "pattern"; //$NON-NLS-1$
private static final String ID_ATTRIBUTE= "id"; //$NON-NLS-1$
/**
* @deprecated as of 3.0 use {@link FilterDescriptor#TARGET_ID_ATTRIBUTE}
*/
@Deprecated
private static final String VIEW_ID_ATTRIBUTE= "viewId"; //$NON-NLS-1$
private static final String TARGET_ID_ATTRIBUTE= "targetId"; //$NON-NLS-1$
private static final String CLASS_ATTRIBUTE= "class"; //$NON-NLS-1$
private static final String NAME_ATTRIBUTE= "name"; //$NON-NLS-1$
private static final String ENABLED_ATTRIBUTE= "enabled"; //$NON-NLS-1$
private static final String DESCRIPTION_ATTRIBUTE= "description"; //$NON-NLS-1$
/**
* @deprecated use "enabled" instead
*/
@Deprecated
private static final String SELECTED_ATTRIBUTE= "selected"; //$NON-NLS-1$
private static FilterDescriptor[] fgFilterDescriptors;
IConfigurationElement fElement;
/**
* Returns all contributed Java element filters.
*/
public static FilterDescriptor[] getFilterDescriptors() {
if (fgFilterDescriptors == null) {
IExtensionRegistry registory= Platform.getExtensionRegistry();
IConfigurationElement[] elements= registory.getConfigurationElementsFor(CUIPlugin.PLUGIN_ID, EXTENSION_POINT_NAME);
fgFilterDescriptors= createFilterDescriptors(elements);
}
return fgFilterDescriptors;
}
/**
* Returns all Java element filters which
* are contributed to the given view.
*/
public static FilterDescriptor[] getFilterDescriptors(String targetId) {
FilterDescriptor[] filterDescs= FilterDescriptor.getFilterDescriptors();
List<FilterDescriptor> result= new ArrayList<FilterDescriptor>(filterDescs.length);
for (int i= 0; i < filterDescs.length; i++) {
String tid= filterDescs[i].getTargetId();
if (tid == null || tid.equals(targetId))
result.add(filterDescs[i]);
}
return result.toArray(new FilterDescriptor[result.size()]);
}
/**
* Creates a new filter descriptor for the given configuration element.
*/
FilterDescriptor(IConfigurationElement element) {
fElement= element;
// it is either a pattern filter or a custom filter
Assert.isTrue(isPatternFilter() ^ isCustomFilter(), "An extension for extension-point org.eclipse.cdt.ui.CElementFilters does not specify a correct filter"); //$NON-NLS-1$
Assert.isNotNull(getId(), "An extension for extension-point org.eclipse.cdt.ui.CElementFilters does not provide a valid ID"); //$NON-NLS-1$
Assert.isNotNull(getName(), "An extension for extension-point org.eclipse.cdt.ui.CElementFilters does not provide a valid name"); //$NON-NLS-1$
}
/**
* Creates a new <code>ViewerFilter</code>.
* This method is only valid for viewer filters.
*/
public ViewerFilter createViewerFilter() {
if (!isCustomFilter())
return null;
final ViewerFilter[] result= new ViewerFilter[1];
String message= NLS.bind(FilterMessages.FilterDescriptor_filterCreationError_message, getId());
ISafeRunnable code= new SafeRunnable(message) {
/*
* @see org.eclipse.core.runtime.ISafeRunnable#run()
*/
public void run() throws Exception {
result[0]= (ViewerFilter)fElement.createExecutableExtension(CLASS_ATTRIBUTE);
}
};
SafeRunnable.run(code);
return result[0];
}
//---- XML Attribute accessors ---------------------------------------------
/**
* Returns the filter's id.
* <p>
* This attribute is mandatory for custom filters.
* The ID for pattern filters is
* PATTERN_FILTER_ID_PREFIX plus the pattern itself.
* </p>
*/
public String getId() {
if (isPatternFilter()) {
String targetId= getTargetId();
if (targetId == null)
return PATTERN_FILTER_ID_PREFIX + getPattern();
return targetId + PATTERN_FILTER_ID_PREFIX + getPattern();
}
return fElement.getAttribute(ID_ATTRIBUTE);
}
/**
* Returns the filter's name.
* <p>
* If the name of a pattern filter is missing
* then the pattern is used as its name.
* </p>
*/
public String getName() {
String name= fElement.getAttribute(NAME_ATTRIBUTE);
if (name == null && isPatternFilter())
name= getPattern();
return name;
}
/**
* Returns the filter's pattern.
*
* @return the pattern string or <code>null</code> if it's not a pattern filter
*/
public String getPattern() {
return fElement.getAttribute(PATTERN_ATTRIBUTE);
}
/**
* Returns the filter's viewId.
*
* @return the view ID or <code>null</code> if the filter is for all views
* @since 3.0
*/
public String getTargetId() {
String tid= fElement.getAttribute(TARGET_ID_ATTRIBUTE);
if (tid != null)
return tid;
// Backwards compatibility code
return fElement.getAttribute(VIEW_ID_ATTRIBUTE);
}
/**
* Returns the filter's description.
*
* @return the description or <code>null</code> if no description is provided
*/
public String getDescription() {
String description= fElement.getAttribute(DESCRIPTION_ATTRIBUTE);
if (description == null)
description= ""; //$NON-NLS-1$
return description;
}
/**
* @return <code>true</code> if this filter is a custom filter.
*/
public boolean isPatternFilter() {
return getPattern() != null;
}
/**
* @return <code>true</code> if this filter is a pattern filter.
*/
public boolean isCustomFilter() {
return fElement.getAttribute(CLASS_ATTRIBUTE) != null;
}
/**
* Returns <code>true</code> if the filter
* is initially enabled.
*
* This attribute is optional and defaults to <code>true</code>.
*/
public boolean isEnabled() {
String strVal= fElement.getAttribute(ENABLED_ATTRIBUTE);
if (strVal == null)
// backward compatibility
strVal= fElement.getAttribute(SELECTED_ATTRIBUTE);
return strVal == null || Boolean.valueOf(strVal).booleanValue();
}
/*
* Implements a method from IComparable
*/
public int compareTo(FilterDescriptor o) {
return Collator.getInstance().compare(getName(), (o).getName());
}
//---- initialization ---------------------------------------------------
/**
* Creates the filter descriptors.
*/
private static FilterDescriptor[] createFilterDescriptors(IConfigurationElement[] elements) {
List<FilterDescriptor> result= new ArrayList<FilterDescriptor>(5);
Set<String> descIds= new HashSet<String>(5);
for (int i= 0; i < elements.length; i++) {
final IConfigurationElement element= elements[i];
if (FILTER_TAG.equals(element.getName())) {
final FilterDescriptor[] desc= new FilterDescriptor[1];
SafeRunnable.run(new SafeRunnable(FilterMessages.FilterDescriptor_filterDescriptionCreationError_message) {
public void run() throws Exception {
desc[0]= new FilterDescriptor(element);
}
});
if (desc[0] != null && !descIds.contains(desc[0].getId())) {
result.add(desc[0]);
descIds.add(desc[0].getId());
}
}
}
Collections.sort(result);
return result.toArray(new FilterDescriptor[result.size()]);
}
}