net.sourceforge.phpeclipse.ui/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 net.sourceforge.phpeclipse.ui.WebUI;
  23
  24 import org.eclipse.core.runtime.IConfigurationElement;
  25 import org.eclipse.core.runtime.IExtensionRegistry;
  26 import org.eclipse.core.runtime.ISafeRunnable;
  27 import org.eclipse.core.runtime.Platform;
  28 import org.eclipse.jface.util.Assert;
  29 import org.eclipse.jface.util.SafeRunnable;
  30 import org.eclipse.jface.viewers.ViewerFilter;
  31 import org.eclipse.ui.IPluginContribution;
  32 import org.eclipse.ui.activities.WorkbenchActivityHelper;
  33
  34 /**
  35  * Represents a custom filter which is provided by the
  36  * "net.sourceforge.phpdt.ui.javaElementFilters" extension point.
  37  *
  38  * since 2.0
  39  */
  40 public class FilterDescriptor implements Comparable, IPluginContribution {
  41
  42         private static String PATTERN_FILTER_ID_PREFIX = "_patternFilterId_"; //$NON-NLS-1$
  43
  44         private static final String EXTENSION_POINT_NAME = "phpElementFilters"; //$NON-NLS-1$
  45
  46         private static final String FILTER_TAG = "filter"; //$NON-NLS-1$
  47
  48         private static final String PATTERN_ATTRIBUTE = "pattern"; //$NON-NLS-1$
  49
  50         private static final String ID_ATTRIBUTE = "id"; //$NON-NLS-1$
  51
  52         /**
  53          * @deprecated as of 3.0 use {@link FilterDescriptor#TARGET_ID_ATTRIBUTE}
  54          */
  55         private static final String VIEW_ID_ATTRIBUTE = "viewId"; //$NON-NLS-1$
  56
  57         private static final String TARGET_ID_ATTRIBUTE = "targetId"; //$NON-NLS-1$
  58
  59         private static final String CLASS_ATTRIBUTE = "class"; //$NON-NLS-1$
  60
  61         private static final String NAME_ATTRIBUTE = "name"; //$NON-NLS-1$
  62
  63         private static final String ENABLED_ATTRIBUTE = "enabled"; //$NON-NLS-1$
  64
  65         private static final String DESCRIPTION_ATTRIBUTE = "description"; //$NON-NLS-1$
  66
  67         /**
  68          * @deprecated use "enabled" instead
  69          */
  70         private static final String SELECTED_ATTRIBUTE = "selected"; //$NON-NLS-1$
  71
  72         private static FilterDescriptor[] fgFilterDescriptors;
  73
  74         private IConfigurationElement fElement;
  75
  76         /**
  77          * Returns all contributed Java element filters.
  78          */
  79         public static FilterDescriptor[] getFilterDescriptors() {
  80                 if (fgFilterDescriptors == null) {
  81                         IExtensionRegistry registry = Platform.getExtensionRegistry();
  82                         IConfigurationElement[] elements = registry
  83                                         .getConfigurationElementsFor(WebUI.PLUGIN_ID,
  84                                                         EXTENSION_POINT_NAME);
  85                         fgFilterDescriptors = createFilterDescriptors(elements);
  86                 }
  87                 return fgFilterDescriptors;
  88         }
  89
  90         /**
  91          * Returns all Java element filters which are contributed to the given view.
  92          */
  93         public static FilterDescriptor[] getFilterDescriptors(String targetId) {
  94                 FilterDescriptor[] filterDescs = FilterDescriptor
  95                                 .getFilterDescriptors();
  96                 List result = new ArrayList(filterDescs.length);
  97                 for (int i = 0; i < filterDescs.length; i++) {
  98                         String tid = filterDescs[i].getTargetId();
  99                         if (WorkbenchActivityHelper.filterItem(filterDescs[i]))
 100                                 continue;
 101                         if (tid == null || tid.equals(targetId))
 102                                 result.add(filterDescs[i]);
 103                 }
 104                 return (FilterDescriptor[]) result.toArray(new FilterDescriptor[result
 105                                 .size()]);
 106         }
 107
 108         /**
 109          * Creates a new filter descriptor for the given configuration element.
 110          */
 111         private FilterDescriptor(IConfigurationElement element) {
 112                 fElement = element;
 113                 // it is either a pattern filter or a custom filter
 114                 Assert
 115                                 .isTrue(
 116                                                 isPatternFilter() ^ isCustomFilter(),
 117                                                 "An extension for extension-point net.sourceforge.phpdt.ui.javaElementFilters does not specify a correct filter"); //$NON-NLS-1$
 118                 Assert
 119                                 .isNotNull(
 120                                                 getId(),
 121                                                 "An extension for extension-point net.sourceforge.phpdt.ui.javaElementFilters does not provide a valid ID"); //$NON-NLS-1$
 122                 Assert
 123                                 .isNotNull(
 124                                                 getName(),
 125                                                 "An extension for extension-point net.sourceforge.phpdt.ui.javaElementFilters does not provide a valid name"); //$NON-NLS-1$
 126         }
 127
 128         /**
 129          * Creates a new <code>ViewerFilter</code>. This method is only valid for
 130          * viewer filters.
 131          */
 132         public ViewerFilter createViewerFilter() {
 133                 if (!isCustomFilter())
 134                         return null;
 135
 136                 final ViewerFilter[] result = new ViewerFilter[1];
 137                 String message = FilterMessages.getFormattedString(
 138                                 "FilterDescriptor.filterCreationError.message", getId()); //$NON-NLS-1$
 139                 ISafeRunnable code = new SafeRunnable(message) {
 140                         /*
 141                          * @see org.eclipse.core.runtime.ISafeRunnable#run()
 142                          */
 143                         public void run() throws Exception {
 144                                 result[0] = (ViewerFilter) fElement
 145                                                 .createExecutableExtension(CLASS_ATTRIBUTE);
 146                         }
 147
 148                 };
 149                 Platform.run(code);
 150                 return result[0];
 151         }
 152
 153         // ---- XML Attribute accessors
 154         // ---------------------------------------------
 155
 156         /**
 157          * Returns the filter's id.
 158          * <p>
 159          * This attribute is mandatory for custom filters. The ID for pattern
 160          * filters is PATTERN_FILTER_ID_PREFIX plus the pattern itself.
 161          * </p>
 162          */
 163         public String getId() {
 164                 if (isPatternFilter()) {
 165                         String targetId = getTargetId();
 166                         if (targetId == null)
 167                                 return PATTERN_FILTER_ID_PREFIX + getPattern();
 168                         else
 169                                 return targetId + PATTERN_FILTER_ID_PREFIX + getPattern();
 170                 } else
 171                         return fElement.getAttribute(ID_ATTRIBUTE);
 172         }
 173
 174         /**
 175          * Returns the filter's name.
 176          * <p>
 177          * If the name of a pattern filter is missing then the pattern is used as
 178          * its name.
 179          * </p>
 180          */
 181         public String getName() {
 182                 String name = fElement.getAttribute(NAME_ATTRIBUTE);
 183                 if (name == null && isPatternFilter())
 184                         name = getPattern();
 185                 return name;
 186         }
 187
 188         /**
 189          * Returns the filter's pattern.
 190          *
 191          * @return the pattern string or <code>null</code> if it's not a pattern
 192          *         filter
 193          */
 194         public String getPattern() {
 195                 return fElement.getAttribute(PATTERN_ATTRIBUTE);
 196         }
 197
 198         /**
 199          * Returns the filter's viewId.
 200          *
 201          * @return the view ID or <code>null</code> if the filter is for all views
 202          * @since 3.0
 203          */
 204         public String getTargetId() {
 205                 String tid = fElement.getAttribute(TARGET_ID_ATTRIBUTE);
 206
 207                 if (tid != null)
 208                         return tid;
 209
 210                 // Backwards compatibility code
 211                 return fElement.getAttribute(VIEW_ID_ATTRIBUTE);
 212
 213         }
 214
 215         /**
 216          * Returns the filter's description.
 217          *
 218          * @return the description or <code>null</code> if no description is
 219          *         provided
 220          */
 221         public String getDescription() {
 222                 String description = fElement.getAttribute(DESCRIPTION_ATTRIBUTE);
 223                 if (description == null)
 224                         description = ""; //$NON-NLS-1$
 225                 return description;
 226         }
 227
 228         /**
 229          * @return <code>true</code> if this filter is a custom filter.
 230          */
 231         public boolean isPatternFilter() {
 232                 return getPattern() != null;
 233         }
 234
 235         /**
 236          * @return <code>true</code> if this filter is a pattern filter.
 237          */
 238         public boolean isCustomFilter() {
 239                 return fElement.getAttribute(CLASS_ATTRIBUTE) != null;
 240         }
 241
 242         /**
 243          * Returns <code>true</code> if the filter is initially enabled.
 244          *
 245          * This attribute is optional and defaults to <code>true</code>.
 246          */
 247         public boolean isEnabled() {
 248                 String strVal = fElement.getAttribute(ENABLED_ATTRIBUTE);
 249                 if (strVal == null)
 250                         // backward compatibility
 251                         strVal = fElement.getAttribute(SELECTED_ATTRIBUTE);
 252                 return strVal == null || Boolean.valueOf(strVal).booleanValue();
 253         }
 254
 255         /*
 256          * Implements a method from IComparable
 257          */
 258         public int compareTo(Object o) {
 259                 if (o instanceof FilterDescriptor)
 260                         return Collator.getInstance().compare(getName(),
 261                                         ((FilterDescriptor) o).getName());
 262                 else
 263                         return Integer.MIN_VALUE;
 264         }
 265
 266         // ---- initialization ---------------------------------------------------
 267
 268         /**
 269          * Creates the filter descriptors.
 270          */
 271         private static FilterDescriptor[] createFilterDescriptors(
 272                         IConfigurationElement[] elements) {
 273                 List result = new ArrayList(5);
 274                 Set descIds = new HashSet(5);
 275                 for (int i = 0; i < elements.length; i++) {
 276                         final IConfigurationElement element = elements[i];
 277                         if (FILTER_TAG.equals(element.getName())) {
 278
 279                                 final FilterDescriptor[] desc = new FilterDescriptor[1];
 280                                 Platform
 281                                                 .run(new SafeRunnable(
 282                                                                 FilterMessages
 283                                                                                 .getString("FilterDescriptor.filterDescriptionCreationError.message")) { //$NON-NLS-1$
 284                                                         public void run() throws Exception {
 285                                                                 desc[0] = new FilterDescriptor(element);
 286                                                         }
 287                                                 });
 288
 289                                 if (desc[0] != null && !descIds.contains(desc[0].getId())) {
 290                                         result.add(desc[0]);
 291                                         descIds.add(desc[0].getId());
 292                                 }
 293                         }
 294                 }
 295                 Collections.sort(result);
 296                 return (FilterDescriptor[]) result.toArray(new FilterDescriptor[result
 297                                 .size()]);
 298         }
 299
 300         public String getLocalId() {
 301                 return fElement.getAttribute(ID_ATTRIBUTE);
 302         }
 303
 304         public String getPluginId() {
 305                 return fElement.getDeclaringExtension().getNamespace();
 306         }
 307
 308 }