net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/filters/FilterDescriptor.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2004 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpdt.internal.ui.filters;
  12
  13 import java.text.Collator;
  14 import java.util.ArrayList;
  15 import java.util.Collections;
  16 import java.util.HashSet;
  17 import java.util.List;
  18 import java.util.Set;
  19
  20 import net.sourceforge.phpeclipse.PHPeclipsePlugin;
  21
  22 import org.eclipse.core.runtime.IConfigurationElement;
  23 import org.eclipse.core.runtime.IExtensionRegistry;
  24 import org.eclipse.core.runtime.ISafeRunnable;
  25 import org.eclipse.core.runtime.Platform;
  26 import org.eclipse.jface.util.Assert;
  27 import org.eclipse.jface.util.SafeRunnable;
  28 import org.eclipse.jface.viewers.ViewerFilter;
  29 import org.eclipse.ui.IPluginContribution;
  30 import org.eclipse.ui.activities.WorkbenchActivityHelper;
  31
  32 /**
  33  * Represents a custom filter which is provided by the
  34  * "net.sourceforge.phpdt.ui.javaElementFilters" extension point.
  35  *
  36  * since 2.0
  37  */
  38 public class FilterDescriptor implements Comparable, IPluginContribution {
  39
  40         private static String PATTERN_FILTER_ID_PREFIX = "_patternFilterId_"; //$NON-NLS-1$
  41
  42         private static final String EXTENSION_POINT_NAME = "phpElementFilters"; //$NON-NLS-1$
  43
  44         private static final String FILTER_TAG = "filter"; //$NON-NLS-1$
  45
  46         private static final String PATTERN_ATTRIBUTE = "pattern"; //$NON-NLS-1$
  47
  48         private static final String ID_ATTRIBUTE = "id"; //$NON-NLS-1$
  49
  50         /**
  51          * @deprecated as of 3.0 use {@link FilterDescriptor#TARGET_ID_ATTRIBUTE}
  52          */
  53         private static final String VIEW_ID_ATTRIBUTE = "viewId"; //$NON-NLS-1$
  54
  55         private static final String TARGET_ID_ATTRIBUTE = "targetId"; //$NON-NLS-1$
  56
  57         private static final String CLASS_ATTRIBUTE = "class"; //$NON-NLS-1$
  58
  59         private static final String NAME_ATTRIBUTE = "name"; //$NON-NLS-1$
  60
  61         private static final String ENABLED_ATTRIBUTE = "enabled"; //$NON-NLS-1$
  62
  63         private static final String DESCRIPTION_ATTRIBUTE = "description"; //$NON-NLS-1$
  64
  65         /**
  66          * @deprecated use "enabled" instead
  67          */
  68         private static final String SELECTED_ATTRIBUTE = "selected"; //$NON-NLS-1$
  69
  70         private static FilterDescriptor[] fgFilterDescriptors;
  71
  72         private IConfigurationElement fElement;
  73
  74         /**
  75          * Returns all contributed Java element filters.
  76          */
  77         public static FilterDescriptor[] getFilterDescriptors() {
  78                 if (fgFilterDescriptors == null) {
  79                         IExtensionRegistry registry = Platform.getExtensionRegistry();
  80                         IConfigurationElement[] elements = registry
  81                                         .getConfigurationElementsFor(PHPeclipsePlugin.PLUGIN_ID,
  82                                                         EXTENSION_POINT_NAME);
  83                         fgFilterDescriptors = createFilterDescriptors(elements);
  84                 }
  85                 return fgFilterDescriptors;
  86         }
  87
  88         /**
  89          * Returns all Java element filters which are contributed to the given view.
  90          */
  91         public static FilterDescriptor[] getFilterDescriptors(String targetId) {
  92                 FilterDescriptor[] filterDescs = FilterDescriptor
  93                                 .getFilterDescriptors();
  94                 List result = new ArrayList(filterDescs.length);
  95                 for (int i = 0; i < filterDescs.length; i++) {
  96                         String tid = filterDescs[i].getTargetId();
  97                         if (WorkbenchActivityHelper.filterItem(filterDescs[i]))
  98                                 continue;
  99                         if (tid == null || tid.equals(targetId))
 100                                 result.add(filterDescs[i]);
 101                 }
 102                 return (FilterDescriptor[]) result.toArray(new FilterDescriptor[result
 103                                 .size()]);
 104         }
 105
 106         /**
 107          * Creates a new filter descriptor for the given configuration element.
 108          */
 109         private FilterDescriptor(IConfigurationElement element) {
 110                 fElement = element;
 111                 // it is either a pattern filter or a custom filter
 112                 Assert
 113                                 .isTrue(
 114                                                 isPatternFilter() ^ isCustomFilter(),
 115                                                 "An extension for extension-point net.sourceforge.phpdt.ui.javaElementFilters does not specify a correct filter"); //$NON-NLS-1$
 116                 Assert
 117                                 .isNotNull(
 118                                                 getId(),
 119                                                 "An extension for extension-point net.sourceforge.phpdt.ui.javaElementFilters does not provide a valid ID"); //$NON-NLS-1$
 120                 Assert
 121                                 .isNotNull(
 122                                                 getName(),
 123                                                 "An extension for extension-point net.sourceforge.phpdt.ui.javaElementFilters does not provide a valid name"); //$NON-NLS-1$
 124         }
 125
 126         /**
 127          * Creates a new <code>ViewerFilter</code>. This method is only valid for
 128          * viewer filters.
 129          */
 130         public ViewerFilter createViewerFilter() {
 131                 if (!isCustomFilter())
 132                         return null;
 133
 134                 final ViewerFilter[] result = new ViewerFilter[1];
 135                 String message = FilterMessages.getFormattedString(
 136                                 "FilterDescriptor.filterCreationError.message", getId()); //$NON-NLS-1$
 137                 ISafeRunnable code = new SafeRunnable(message) {
 138                         /*
 139                          * @see org.eclipse.core.runtime.ISafeRunnable#run()
 140                          */
 141                         public void run() throws Exception {
 142                                 result[0] = (ViewerFilter) fElement
 143                                                 .createExecutableExtension(CLASS_ATTRIBUTE);
 144                         }
 145
 146                 };
 147                 Platform.run(code);
 148                 return result[0];
 149         }
 150
 151         // ---- XML Attribute accessors
 152         // ---------------------------------------------
 153
 154         /**
 155          * Returns the filter's id.
 156          * <p>
 157          * This attribute is mandatory for custom filters. The ID for pattern
 158          * filters is PATTERN_FILTER_ID_PREFIX plus the pattern itself.
 159          * </p>
 160          */
 161         public String getId() {
 162                 if (isPatternFilter()) {
 163                         String targetId = getTargetId();
 164                         if (targetId == null)
 165                                 return PATTERN_FILTER_ID_PREFIX + getPattern();
 166                         else
 167                                 return targetId + PATTERN_FILTER_ID_PREFIX + getPattern();
 168                 } else
 169                         return fElement.getAttribute(ID_ATTRIBUTE);
 170         }
 171
 172         /**
 173          * Returns the filter's name.
 174          * <p>
 175          * If the name of a pattern filter is missing then the pattern is used as
 176          * its name.
 177          * </p>
 178          */
 179         public String getName() {
 180                 String name = fElement.getAttribute(NAME_ATTRIBUTE);
 181                 if (name == null && isPatternFilter())
 182                         name = getPattern();
 183                 return name;
 184         }
 185
 186         /**
 187          * Returns the filter's pattern.
 188          *
 189          * @return the pattern string or <code>null</code> if it's not a pattern
 190          *         filter
 191          */
 192         public String getPattern() {
 193                 return fElement.getAttribute(PATTERN_ATTRIBUTE);
 194         }
 195
 196         /**
 197          * Returns the filter's viewId.
 198          *
 199          * @return the view ID or <code>null</code> if the filter is for all views
 200          * @since 3.0
 201          */
 202         public String getTargetId() {
 203                 String tid = fElement.getAttribute(TARGET_ID_ATTRIBUTE);
 204
 205                 if (tid != null)
 206                         return tid;
 207
 208                 // Backwards compatibility code
 209                 return fElement.getAttribute(VIEW_ID_ATTRIBUTE);
 210
 211         }
 212
 213         /**
 214          * Returns the filter's description.
 215          *
 216          * @return the description or <code>null</code> if no description is
 217          *         provided
 218          */
 219         public String getDescription() {
 220                 String description = fElement.getAttribute(DESCRIPTION_ATTRIBUTE);
 221                 if (description == null)
 222                         description = ""; //$NON-NLS-1$
 223                 return description;
 224         }
 225
 226         /**
 227          * @return <code>true</code> if this filter is a custom filter.
 228          */
 229         public boolean isPatternFilter() {
 230                 return getPattern() != null;
 231         }
 232
 233         /**
 234          * @return <code>true</code> if this filter is a pattern filter.
 235          */
 236         public boolean isCustomFilter() {
 237                 return fElement.getAttribute(CLASS_ATTRIBUTE) != null;
 238         }
 239
 240         /**
 241          * Returns <code>true</code> if the filter is initially enabled.
 242          *
 243          * This attribute is optional and defaults to <code>true</code>.
 244          */
 245         public boolean isEnabled() {
 246                 String strVal = fElement.getAttribute(ENABLED_ATTRIBUTE);
 247                 if (strVal == null)
 248                         // backward compatibility
 249                         strVal = fElement.getAttribute(SELECTED_ATTRIBUTE);
 250                 return strVal == null || Boolean.valueOf(strVal).booleanValue();
 251         }
 252
 253         /*
 254          * Implements a method from IComparable
 255          */
 256         public int compareTo(Object o) {
 257                 if (o instanceof FilterDescriptor)
 258                         return Collator.getInstance().compare(getName(),
 259                                         ((FilterDescriptor) o).getName());
 260                 else
 261                         return Integer.MIN_VALUE;
 262         }
 263
 264         // ---- initialization ---------------------------------------------------
 265
 266         /**
 267          * Creates the filter descriptors.
 268          */
 269         private static FilterDescriptor[] createFilterDescriptors(
 270                         IConfigurationElement[] elements) {
 271                 List result = new ArrayList(5);
 272                 Set descIds = new HashSet(5);
 273                 for (int i = 0; i < elements.length; i++) {
 274                         final IConfigurationElement element = elements[i];
 275                         if (FILTER_TAG.equals(element.getName())) {
 276
 277                                 final FilterDescriptor[] desc = new FilterDescriptor[1];
 278                                 Platform
 279                                                 .run(new SafeRunnable(
 280                                                                 FilterMessages
 281                                                                                 .getString("FilterDescriptor.filterDescriptionCreationError.message")) { //$NON-NLS-1$
 282                                                         public void run() throws Exception {
 283                                                                 desc[0] = new FilterDescriptor(element);
 284                                                         }
 285                                                 });
 286
 287                                 if (desc[0] != null && !descIds.contains(desc[0].getId())) {
 288                                         result.add(desc[0]);
 289                                         descIds.add(desc[0].getId());
 290                                 }
 291                         }
 292                 }
 293                 Collections.sort(result);
 294                 return (FilterDescriptor[]) result.toArray(new FilterDescriptor[result
 295                                 .size()]);
 296         }
 297
 298         public String getLocalId() {
 299                 return fElement.getAttribute(ID_ATTRIBUTE);
 300         }
 301
 302         public String getPluginId() {
 303                 return fElement.getDeclaringExtension().getNamespace();
 304         }
 305
 306 }