net.sourceforge.phpeclipse.ui/src/net/sourceforge/phpdt/internal/ui/text/template/preferences/TemplateVariableProcessor.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.text.template.preferences;
  12
  13 import java.util.ArrayList;
  14 import java.util.Collections;
  15 import java.util.Comparator;
  16 import java.util.Iterator;
  17 import java.util.List;
  18
  19 import org.eclipse.jface.text.ITextViewer;
  20 import org.eclipse.jface.text.contentassist.ICompletionProposal;
  21 import org.eclipse.jface.text.contentassist.IContentAssistProcessor;
  22 import org.eclipse.jface.text.contentassist.IContextInformation;
  23 import org.eclipse.jface.text.contentassist.IContextInformationValidator;
  24 import org.eclipse.jface.text.templates.TemplateContextType;
  25 import org.eclipse.jface.text.templates.TemplateVariableResolver;
  26
  27 public class TemplateVariableProcessor implements IContentAssistProcessor {
  28
  29         private static Comparator fgTemplateVariableProposalComparator = new Comparator() {
  30                 public int compare(Object arg0, Object arg1) {
  31                         TemplateVariableProposal proposal0 = (TemplateVariableProposal) arg0;
  32                         TemplateVariableProposal proposal1 = (TemplateVariableProposal) arg1;
  33
  34                         return proposal0.getDisplayString().compareTo(
  35                                         proposal1.getDisplayString());
  36                 }
  37
  38                 public boolean equals(Object arg0) {
  39                         return false;
  40                 }
  41         };
  42
  43         /** the context type */
  44         private TemplateContextType fContextType;
  45
  46         /**
  47          * Sets the context type.
  48          */
  49         public void setContextType(TemplateContextType contextType) {
  50                 fContextType = contextType;
  51         }
  52
  53         /**
  54          * Gets the context type.
  55          */
  56         public TemplateContextType getContextType() {
  57                 return fContextType;
  58         }
  59
  60         /*
  61          * @see IContentAssistProcessor#computeCompletionProposals(ITextViewer, int)
  62          */
  63         public ICompletionProposal[] computeCompletionProposals(ITextViewer viewer,
  64                         int documentOffset) {
  65
  66                 if (fContextType == null)
  67                         return null;
  68
  69                 List proposals = new ArrayList();
  70
  71                 String text = viewer.getDocument().get();
  72                 int start = getStart(text, documentOffset);
  73                 int end = documentOffset;
  74
  75                 String string = text.substring(start, end);
  76                 String prefix = (string.length() >= 2) ? string.substring(2) : null;
  77
  78                 int offset = start;
  79                 int length = end - start;
  80
  81                 for (Iterator iterator = fContextType.resolvers(); iterator.hasNext();) {
  82                         TemplateVariableResolver variable = (TemplateVariableResolver) iterator
  83                                         .next();
  84
  85                         if (prefix == null || variable.getType().startsWith(prefix))
  86                                 proposals.add(new TemplateVariableProposal(variable, offset,
  87                                                 length, viewer));
  88                 }
  89
  90                 Collections.sort(proposals, fgTemplateVariableProposalComparator);
  91                 return (ICompletionProposal[]) proposals
  92                                 .toArray(new ICompletionProposal[proposals.size()]);
  93         }
  94
  95         /* Guesses the start position of the completion */
  96         private int getStart(String string, int end) {
  97                 int start = end;
  98
  99                 if (start >= 1 && string.charAt(start - 1) == '$')
 100                         return start - 1;
 101
 102                 while ((start != 0)
 103                                 && Character.isUnicodeIdentifierPart(string.charAt(start - 1)))
 104                         start--;
 105
 106                 if (start >= 2 && string.charAt(start - 1) == '{'
 107                                 && string.charAt(start - 2) == '$')
 108                         return start - 2;
 109
 110                 return end;
 111         }
 112
 113         /*
 114          * @see IContentAssistProcessor#computeContextInformation(ITextViewer, int)
 115          */
 116         public IContextInformation[] computeContextInformation(ITextViewer viewer,
 117                         int documentOffset) {
 118                 return null;
 119         }
 120
 121         /*
 122          * @see IContentAssistProcessor#getCompletionProposalAutoActivationCharacters()
 123          */
 124         public char[] getCompletionProposalAutoActivationCharacters() {
 125                 return new char[] { '$' };
 126         }
 127
 128         /*
 129          * @see IContentAssistProcessor#getContextInformationAutoActivationCharacters()
 130          */
 131         public char[] getContextInformationAutoActivationCharacters() {
 132                 return null;
 133         }
 134
 135         /*
 136          * @see IContentAssistProcessor#getErrorMessage()
 137          */
 138         public String getErrorMessage() {
 139                 return null;
 140         }
 141
 142         /*
 143          * @see IContentAssistProcessor#getContextInformationValidator()
 144          */
 145         public IContextInformationValidator getContextInformationValidator() {
 146                 return null;
 147         }
 148
 149 }