/*******************************************************************************
* Copyright (c) 2000, 2017 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
*
*******************************************************************************/
package org.eclipse.dltk.internal.ui.filters;
import java.util.ArrayList;
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.core.runtime.SafeRunner;
import org.eclipse.dltk.internal.corext.util.Messages;
import org.eclipse.dltk.ui.DLTKUIPlugin;
import org.eclipse.jface.util.SafeRunnable;
import org.eclipse.jface.viewers.ViewerFilter;
import org.eclipse.ui.IPluginContribution;
import org.eclipse.ui.activities.WorkbenchActivityHelper;
import com.ibm.icu.text.Collator;
/**
* Represents a custom filter which is provided by the
* "org.eclipse.dltk.dltkElementFilters" extension point.
*
*/
public class FilterDescriptor implements Comparable, IPluginContribution {
private static String PATTERN_FILTER_ID_PREFIX = "_patternFilterId_"; //$NON-NLS-1$
private static final String EXTENSION_POINT_NAME = "dltkElementFilters"; //$NON-NLS-1$
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;
private IConfigurationElement fElement;
/**
* Returns all contributed element filters.
*/
public static FilterDescriptor[] getFilterDescriptors() {
if (fgFilterDescriptors == null) {
IExtensionRegistry registry = Platform.getExtensionRegistry();
IConfigurationElement[] elements = registry
.getConfigurationElementsFor(DLTKUIPlugin.PLUGIN_ID,
EXTENSION_POINT_NAME);
fgFilterDescriptors = createFilterDescriptors(elements);
}
return fgFilterDescriptors;
}
/**
* Returns all element filters which are contributed to the given view.
*/
public static FilterDescriptor[] getFilterDescriptors(String targetId) {
FilterDescriptor[] filterDescs = FilterDescriptor
.getFilterDescriptors();
List<FilterDescriptor> result = new ArrayList<>(filterDescs.length);
for (int i = 0; i < filterDescs.length; i++) {
String tid = filterDescs[i].getTargetId();
if (WorkbenchActivityHelper.filterItem(filterDescs[i]))
continue;
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.
*/
private 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.dltk.ui.dltkElementFilters does not specify a correct filter"); //$NON-NLS-1$
Assert.isNotNull(getId(),
"An extension for extension-point org.eclipse.dltk.ui.dltkElementFilters does not provide a valid ID"); //$NON-NLS-1$
Assert.isNotNull(getName(),
"An extension for extension-point org.eclipse.dltk.ui.dltkElementFilters 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 = Messages.format(
FilterMessages.FilterDescriptor_filterCreationError_message,
getId());
ISafeRunnable code = new SafeRunnable(message) {
/*
* @see org.eclipse.core.runtime.ISafeRunnable#run()
*/
@Override
public void run() throws Exception {
result[0] = (ViewerFilter) fElement
.createExecutableExtension(CLASS_ATTRIBUTE);
}
};
SafeRunner.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();
else
return targetId + PATTERN_FILTER_ID_PREFIX + getPattern();
} else
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
*
*/
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
*/
@Override
public int compareTo(Object o) {
if (o instanceof FilterDescriptor)
return Collator.getInstance().compare(getName(),
((FilterDescriptor) o).getName());
else
return Integer.MIN_VALUE;
}
// ---- initialization ---------------------------------------------------
/**
* Creates the filter descriptors.
*/
private static FilterDescriptor[] createFilterDescriptors(
IConfigurationElement[] elements) {
List<FilterDescriptor> result = new ArrayList<>(5);
Set<String> descIds = new HashSet<>(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];
SafeRunner.run(new SafeRunnable(
FilterMessages.FilterDescriptor_filterDescriptionCreationError_message) {
@Override
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());
}
}
}
return result.toArray(new FilterDescriptor[result.size()]);
}
@Override
public String getLocalId() {
return fElement.getAttribute(ID_ATTRIBUTE);
}
@Override
public String getPluginId() {
return fElement.getContributor().getName();
}
}