case-study/jdt-before/ui/org/eclipse/jdt/internal/ui/text/template/contentassist/PositionBasedCompletionProposal.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2008 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Eclipse Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/epl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11
  12 package org.eclipse.jdt.internal.ui.text.template.contentassist;
  13
  14
  15 import org.eclipse.swt.graphics.Image;
  16 import org.eclipse.swt.graphics.Point;
  17
  18 import org.eclipse.core.runtime.Assert;
  19
  20 import org.eclipse.jface.text.BadLocationException;
  21 import org.eclipse.jface.text.DocumentEvent;
  22 import org.eclipse.jface.text.IDocument;
  23 import org.eclipse.jface.text.ITextViewer;
  24 import org.eclipse.jface.text.Position;
  25 import org.eclipse.jface.text.contentassist.ICompletionProposal;
  26 import org.eclipse.jface.text.contentassist.ICompletionProposalExtension;
  27 import org.eclipse.jface.text.contentassist.ICompletionProposalExtension2;
  28 import org.eclipse.jface.text.contentassist.IContextInformation;
  29
  30
  31 /**
  32  * An enhanced implementation of the <code>ICompletionProposal</code> interface implementing all the extension interfaces.
  33  * It uses a position to track its replacement offset and length. The position must be set up externally.
  34  */
  35 public class PositionBasedCompletionProposal implements ICompletionProposal, ICompletionProposalExtension, ICompletionProposalExtension2 {
  36
  37         /** The string to be displayed in the completion proposal popup */
  38         private String fDisplayString;
  39         /** The replacement string */
  40         private String fReplacementString;
  41         /** The replacement position. */
  42         private Position fReplacementPosition;
  43         /** The cursor position after this proposal has been applied */
  44         private int fCursorPosition;
  45         /** The image to be displayed in the completion proposal popup */
  46         private Image fImage;
  47         /** The context information of this proposal */
  48         private IContextInformation fContextInformation;
  49         /** The additional info of this proposal */
  50         private String fAdditionalProposalInfo;
  51         /** The trigger characters */
  52         private char[] fTriggerCharacters;
  53
  54         /**
  55          * Creates a new completion proposal based on the provided information.  The replacement string is
  56          * considered being the display string too. All remaining fields are set to <code>null</code>.
  57          *
  58          * @param replacementString the actual string to be inserted into the document
  59          * @param replacementPosition the position of the text to be replaced
  60          * @param cursorPosition the position of the cursor following the insert relative to replacementOffset
  61          */
  62         public PositionBasedCompletionProposal(String replacementString, Position replacementPosition, int cursorPosition) {
  63                 this(replacementString, replacementPosition, cursorPosition, null, null, null, null, null);
  64         }
  65
  66         /**
  67          * Creates a new completion proposal. All fields are initialized based on the provided information.
  68          *
  69          * @param replacementString the actual string to be inserted into the document
  70          * @param replacementPosition the position of the text to be replaced
  71          * @param cursorPosition the position of the cursor following the insert relative to replacementOffset
  72          * @param image the image to display for this proposal
  73          * @param displayString the string to be displayed for the proposal
  74          * @param contextInformation the context information associated with this proposal
  75          * @param additionalProposalInfo the additional information associated with this proposal
  76          * @param triggers the trigger characters
  77          */
  78         public PositionBasedCompletionProposal(String replacementString, Position replacementPosition, int cursorPosition, Image image, String displayString, IContextInformation contextInformation, String additionalProposalInfo, char[] triggers) {
  79                 Assert.isNotNull(replacementString);
  80                 Assert.isTrue(replacementPosition != null);
  81
  82                 fReplacementString= replacementString;
  83                 fReplacementPosition= replacementPosition;
  84                 fCursorPosition= cursorPosition;
  85                 fImage= image;
  86                 fDisplayString= displayString;
  87                 fContextInformation= contextInformation;
  88                 fAdditionalProposalInfo= additionalProposalInfo;
  89                 fTriggerCharacters= triggers;
  90         }
  91
  92         /*
  93          * @see ICompletionProposal#apply(IDocument)
  94          */
  95         public void apply(IDocument document) {
  96                 try {
  97                         document.replace(fReplacementPosition.getOffset(), fReplacementPosition.getLength(), fReplacementString);
  98                 } catch (BadLocationException x) {
  99                         // ignore
 100                 }
 101         }
 102
 103         /*
 104          * @see ICompletionProposal#getSelection(IDocument)
 105          */
 106         public Point getSelection(IDocument document) {
 107                 return new Point(fReplacementPosition.getOffset() + fCursorPosition, 0);
 108         }
 109
 110         /*
 111          * @see ICompletionProposal#getContextInformation()
 112          */
 113         public IContextInformation getContextInformation() {
 114                 return fContextInformation;
 115         }
 116
 117         /*
 118          * @see ICompletionProposal#getImage()
 119          */
 120         public Image getImage() {
 121                 return fImage;
 122         }
 123
 124         /*
 125          * @see org.eclipse.jface.text.contentassist.ICompletionProposal#getDisplayString()
 126          */
 127         public String getDisplayString() {
 128                 if (fDisplayString != null)
 129                         return fDisplayString;
 130                 return fReplacementString;
 131         }
 132
 133         /*
 134          * @see ICompletionProposal#getAdditionalProposalInfo()
 135          */
 136         public String getAdditionalProposalInfo() {
 137                 return fAdditionalProposalInfo;
 138         }
 139
 140         /*
 141          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#apply(org.eclipse.jface.text.ITextViewer, char, int, int)
 142          */
 143         public void apply(ITextViewer viewer, char trigger, int stateMask, int offset) {
 144                 apply(viewer.getDocument());
 145         }
 146
 147         /*
 148          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#selected(org.eclipse.jface.text.ITextViewer, boolean)
 149          */
 150         public void selected(ITextViewer viewer, boolean smartToggle) {
 151         }
 152
 153         /*
 154          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#unselected(org.eclipse.jface.text.ITextViewer)
 155          */
 156         public void unselected(ITextViewer viewer) {
 157         }
 158
 159         /*
 160          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#validate(org.eclipse.jface.text.IDocument, int, org.eclipse.jface.text.DocumentEvent)
 161          */
 162         public boolean validate(IDocument document, int offset, DocumentEvent event) {
 163                 try {
 164                         String content= document.get(fReplacementPosition.getOffset(), offset - fReplacementPosition.getOffset());
 165                         if (fReplacementString.startsWith(content))
 166                                 return true;
 167                 } catch (BadLocationException e) {
 168                         // ignore concurrently modified document
 169                 }
 170                 return false;
 171         }
 172
 173         /*
 174          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension#apply(org.eclipse.jface.text.IDocument, char, int)
 175          */
 176         public void apply(IDocument document, char trigger, int offset) {
 177                 // not called any more
 178         }
 179
 180         /*
 181          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension#isValidFor(org.eclipse.jface.text.IDocument, int)
 182          */
 183         public boolean isValidFor(IDocument document, int offset) {
 184                 // not called any more
 185                 return false;
 186         }
 187
 188         /*
 189          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension#getTriggerCharacters()
 190          */
 191         public char[] getTriggerCharacters() {
 192                 return fTriggerCharacters;
 193         }
 194
 195         /*
 196          * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension#getContextInformationPosition()
 197          */
 198         public int getContextInformationPosition() {
 199                 return fReplacementPosition.getOffset();
 200         }
 201
 202 }
 203