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