bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/dialogs/PatternFilter.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004 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.ui.dialogs;

 import java.text.BreakIterator;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 import org.eclipse.jface.viewers.AbstractTreeViewer;
 import org.eclipse.jface.viewers.ILabelProvider;
 import org.eclipse.jface.viewers.ITreeContentProvider;
 import org.eclipse.jface.viewers.StructuredViewer;
 import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.jface.viewers.ViewerFilter;
 import org.eclipse.ui.internal.misc.StringMatcher;

 /**
  * A filter used in conjunction with <code>FilteredTree</code>.  In order to
  * determine if a node should be filtered it uses the content provider of the
  * tree to do pattern matching on its children.  This causes the entire tree
  * structure to be realized.
  *
  * @see org.eclipse.ui.dialogs.FilteredTree
  * @since 3.2
  */
 public class PatternFilter extends ViewerFilter {
 	/*
 	 * Cache of filtered elements in the tree
 	 */
     private Map cache = new HashMap();

 	/**
 	 * Whether to include a leading wildcard for all provided patterns.  A
 	 * trailing wildcard is always included.
 	 */
 	private boolean includeLeadingWildcard = false;

 	/**
 	 * The string pattern matcher used for this pattern filter.
 	 */
     private StringMatcher matcher;

     /* (non-Javadoc)
      * @see org.eclipse.jface.viewers.ViewerFilter#filter(org.eclipse.jface.viewers.Viewer, java.lang.Object, java.lang.Object[])
      */
     public final Object[] filter(Viewer viewer, Object parent, Object[] elements) {
         if (matcher == null) {
 			return elements;
 		}

         Object[] filtered = (Object[]) cache.get(parent);
         if (filtered == null) {
             filtered = super.filter(viewer, parent, elements);
             cache.put(parent, filtered);
         }
         return filtered;
     }

     /* (non-Javadoc)
      * @see org.eclipse.jface.viewers.ViewerFilter#select(org.eclipse.jface.viewers.Viewer, java.lang.Object, java.lang.Object)
      */
     public final boolean select(Viewer viewer, Object parentElement,
 			Object element) {
         return isElementVisible(viewer, element);
     }

     /**
 	 * Sets whether a leading wildcard should be attached to each pattern
 	 * string.
 	 *
 	 * @param includeLeadingWildcard
 	 *            Whether a leading wildcard should be added.
 	 */
 	public final void setIncludeLeadingWildcard(
 			final boolean includeLeadingWildcard) {
 		this.includeLeadingWildcard = includeLeadingWildcard;
 	}

     /**
      * The pattern string for which this filter should select
      * elements in the viewer.
      *
      * @param patternString
      */
     public void setPattern(String patternString) {
         cache.clear();
         if (patternString == null || patternString.equals("")) { //$NON-NLS-1$
 			matcher = null;
 		} else {
 			String pattern = patternString + "*"; //$NON-NLS-1$
 			if (includeLeadingWildcard) {
 				pattern = "*" + pattern; //$NON-NLS-1$
 			}
 			matcher = new StringMatcher(pattern, true, false);
 		}
     }

     /**
      * Answers whether the given String matches the pattern.
      *
      * @param string the String to test
      *
      * @return whether the string matches the pattern
      */
     private boolean match(String string) {
     	if (matcher == null) {
 			return true;
 		}
         return matcher.match(string);
     }

     /**
      * Answers whether the given element is a valid selection in
      * the filtered tree.  For example, if a tree has items that
      * are categorized, the category itself may  not be a valid
      * selection since it is used merely to organize the elements.
      *
      * @param element
      * @return true if this element is eligible for automatic selection
      */
     public boolean isElementSelectable(Object element){
     	return element != null;
     }

     /**
      * Answers whether the given element in the given viewer matches
      * the filter pattern.  This is a default implementation that will
      * show a leaf element in the tree based on whether the provided
      * filter text matches the text of the given element's text, or that
      * of it's children (if the element has any).
      *
      * Subclasses may override this method.
      *
      * @param viewer the tree viewer in which the element resides
      * @param element the element in the tree to check for a match
      *
      * @return true if the element matches the filter pattern
      */
     public boolean isElementVisible(Viewer viewer, Object element){
     	return isParentMatch(viewer, element) || isLeafMatch(viewer, element);
     }

     /**
      * Check if the parent (category) is a match to the filter text.  The default
      * behavior returns true if the element has at least one child element that is
      * a match with the filter text.
      *
      * Subclasses may override this method.
      *
      * @param viewer the viewer that contains the element
      * @param element the tree element to check
      * @return true if the given element has children that matches the filter text
      */
     protected boolean isParentMatch(Viewer viewer, Object element){
         Object[] children = ((ITreeContentProvider) ((AbstractTreeViewer) viewer)
                 .getContentProvider()).getChildren(element);

         if ((children != null) && (children.length > 0)) {
 			return filter(viewer, element, children).length > 0;
 		}
         return false;
     }

     /**
      * Check if the current (leaf) element is a match with the filter text.
      * The default behavior checks that the label of the element is a match.
      *
      * Subclasses should override this method.
      *
      * @param viewer the viewer that contains the element
      * @param element the tree element to check
      * @return true if the given element's label matches the filter text
      */
     protected boolean isLeafMatch(Viewer viewer, Object element){
         String labelText = ((ILabelProvider) ((StructuredViewer) viewer)
                 .getLabelProvider()).getText(element);

         if(labelText == null) {
 			return false;
 		}
         return wordMatches(labelText);
     }

     /**
      * Take the given filter text and break it down into words using a
      * BreakIterator.
      *
      * @param text
      * @return an array of words
      */
     private String[] getWords(String text){
     	List words = new ArrayList();
 		// Break the text up into words, separating based on whitespace and
 		// common punctuation.
 		// Previously used String.split(..., "\\W"), where "\W" is a regular
 		// expression (see the Javadoc for class Pattern).
 		// Need to avoid both String.split and regular expressions, in order to
 		// compile against JCL Foundation (bug 80053).
 		// Also need to do this in an NL-sensitive way. The use of BreakIterator
 		// was suggested in bug 90579.
 		BreakIterator iter = BreakIterator.getWordInstance();
 		iter.setText(text);
 		int i = iter.first();
 		while (i != java.text.BreakIterator.DONE && i < text.length()) {
 			int j = iter.following(i);
 			if (j == java.text.BreakIterator.DONE) {
 				j = text.length();
 			}
 			// match the word
 			if (Character.isLetterOrDigit(text.charAt(i))) {
 				String word = text.substring(i, j);
 				words.add(word);
 			}
 			i = j;
 		}
 		return (String[]) words.toArray(new String[words.size()]);
     }

 	/**
 	 * Return whether or not if any of the words in text satisfy the
 	 * match critera.
 	 *
 	 * @param text the text to match
 	 * @return boolean <code>true</code> if one of the words in text
 	 * 					satisifes the match criteria.
 	 */
 	protected boolean wordMatches(String text) {
 		if (text == null) {
 			return false;
 		}

 		//If the whole text matches we are all set
 		if(match(text)) {
 			return true;
 		}

 		// Otherwise check if any of the words of the text matches
 		String[] words = getWords(text);
 		for (int i = 0; i < words.length; i++) {
 			String word = words[i];
 			if (match(word)) {
 				return true;
 			}
 		}

 		return false;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2004 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.ui.dialogs;

	import java.text.BreakIterator;
	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;

	import org.eclipse.jface.viewers.AbstractTreeViewer;
	import org.eclipse.jface.viewers.ILabelProvider;
	import org.eclipse.jface.viewers.ITreeContentProvider;
	import org.eclipse.jface.viewers.StructuredViewer;
	import org.eclipse.jface.viewers.Viewer;
	import org.eclipse.jface.viewers.ViewerFilter;
	import org.eclipse.ui.internal.misc.StringMatcher;

	/**
	* A filter used in conjunction with <code>FilteredTree</code>. In order to
	* determine if a node should be filtered it uses the content provider of the
	* tree to do pattern matching on its children. This causes the entire tree
	* structure to be realized.
	*
	* @see org.eclipse.ui.dialogs.FilteredTree
	* @since 3.2
	*/
	public class PatternFilter extends ViewerFilter {
	/*
	* Cache of filtered elements in the tree
	*/
	private Map cache = new HashMap();

	/**
	* Whether to include a leading wildcard for all provided patterns. A
	* trailing wildcard is always included.
	*/
	private boolean includeLeadingWildcard = false;

	/**
	* The string pattern matcher used for this pattern filter.
	*/
	private StringMatcher matcher;

	/* (non-Javadoc)
	* @see org.eclipse.jface.viewers.ViewerFilter#filter(org.eclipse.jface.viewers.Viewer, java.lang.Object, java.lang.Object[])
	*/
	public final Object[] filter(Viewer viewer, Object parent, Object[] elements) {
	if (matcher == null) {
	return elements;
	}

	Object[] filtered = (Object[]) cache.get(parent);
	if (filtered == null) {
	filtered = super.filter(viewer, parent, elements);
	cache.put(parent, filtered);
	}
	return filtered;
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.viewers.ViewerFilter#select(org.eclipse.jface.viewers.Viewer, java.lang.Object, java.lang.Object)
	*/
	public final boolean select(Viewer viewer, Object parentElement,
	Object element) {
	return isElementVisible(viewer, element);
	}

	/**
	* Sets whether a leading wildcard should be attached to each pattern
	* string.
	*
	* @param includeLeadingWildcard
	* Whether a leading wildcard should be added.
	*/
	public final void setIncludeLeadingWildcard(
	final boolean includeLeadingWildcard) {
	this.includeLeadingWildcard = includeLeadingWildcard;
	}

	/**
	* The pattern string for which this filter should select
	* elements in the viewer.
	*
	* @param patternString
	*/
	public void setPattern(String patternString) {
	cache.clear();
	if (patternString == null \|\| patternString.equals("")) { //$NON-NLS-1$
	matcher = null;
	} else {
	String pattern = patternString + "*"; //$NON-NLS-1$
	if (includeLeadingWildcard) {
	pattern = "*" + pattern; //$NON-NLS-1$
	}
	matcher = new StringMatcher(pattern, true, false);
	}
	}

	/**
	* Answers whether the given String matches the pattern.
	*
	* @param string the String to test
	*
	* @return whether the string matches the pattern
	*/
	private boolean match(String string) {
	if (matcher == null) {
	return true;
	}
	return matcher.match(string);
	}

	/**
	* Answers whether the given element is a valid selection in
	* the filtered tree. For example, if a tree has items that
	* are categorized, the category itself may not be a valid
	* selection since it is used merely to organize the elements.
	*
	* @param element
	* @return true if this element is eligible for automatic selection
	*/
	public boolean isElementSelectable(Object element){
	return element != null;
	}

	/**
	* Answers whether the given element in the given viewer matches
	* the filter pattern. This is a default implementation that will
	* show a leaf element in the tree based on whether the provided
	* filter text matches the text of the given element's text, or that
	* of it's children (if the element has any).
	*
	* Subclasses may override this method.
	*
	* @param viewer the tree viewer in which the element resides
	* @param element the element in the tree to check for a match
	*
	* @return true if the element matches the filter pattern
	*/
	public boolean isElementVisible(Viewer viewer, Object element){
	return isParentMatch(viewer, element) \|\| isLeafMatch(viewer, element);
	}

	/**
	* Check if the parent (category) is a match to the filter text. The default
	* behavior returns true if the element has at least one child element that is
	* a match with the filter text.
	*
	* Subclasses may override this method.
	*
	* @param viewer the viewer that contains the element
	* @param element the tree element to check
	* @return true if the given element has children that matches the filter text
	*/
	protected boolean isParentMatch(Viewer viewer, Object element){
	Object[] children = ((ITreeContentProvider) ((AbstractTreeViewer) viewer)
	.getContentProvider()).getChildren(element);

	if ((children != null) && (children.length > 0)) {
	return filter(viewer, element, children).length > 0;
	}
	return false;
	}

	/**
	* Check if the current (leaf) element is a match with the filter text.
	* The default behavior checks that the label of the element is a match.
	*
	* Subclasses should override this method.
	*
	* @param viewer the viewer that contains the element
	* @param element the tree element to check
	* @return true if the given element's label matches the filter text
	*/
	protected boolean isLeafMatch(Viewer viewer, Object element){
	String labelText = ((ILabelProvider) ((StructuredViewer) viewer)
	.getLabelProvider()).getText(element);

	if(labelText == null) {
	return false;
	}
	return wordMatches(labelText);
	}

	/**
	* Take the given filter text and break it down into words using a
	* BreakIterator.
	*
	* @param text
	* @return an array of words
	*/
	private String[] getWords(String text){
	List words = new ArrayList();
	// Break the text up into words, separating based on whitespace and
	// common punctuation.
	// Previously used String.split(..., "\\W"), where "\W" is a regular
	// expression (see the Javadoc for class Pattern).
	// Need to avoid both String.split and regular expressions, in order to
	// compile against JCL Foundation (bug 80053).
	// Also need to do this in an NL-sensitive way. The use of BreakIterator
	// was suggested in bug 90579.
	BreakIterator iter = BreakIterator.getWordInstance();
	iter.setText(text);
	int i = iter.first();
	while (i != java.text.BreakIterator.DONE && i < text.length()) {
	int j = iter.following(i);
	if (j == java.text.BreakIterator.DONE) {
	j = text.length();
	}
	// match the word
	if (Character.isLetterOrDigit(text.charAt(i))) {
	String word = text.substring(i, j);
	words.add(word);
	}
	i = j;
	}
	return (String[]) words.toArray(new String[words.size()]);
	}

	/**
	* Return whether or not if any of the words in text satisfy the
	* match critera.
	*
	* @param text the text to match
	* @return boolean <code>true</code> if one of the words in text
	* satisifes the match criteria.
	*/
	protected boolean wordMatches(String text) {
	if (text == null) {
	return false;
	}

	//If the whole text matches we are all set
	if(match(text)) {
	return true;
	}

	// Otherwise check if any of the words of the text matches
	String[] words = getWords(text);
	for (int i = 0; i < words.length; i++) {
	String word = words[i];
	if (match(word)) {
	return true;
	}
	}

	return false;
	}
	}