case-study/jdt-before/core extension/org/eclipse/jdt/internal/corext/template/java/JavaDocContext.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2011 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 package org.eclipse.jdt.internal.corext.template.java;
  12
  13 import org.eclipse.jface.preference.IPreferenceStore;
  14
  15 import org.eclipse.jface.text.BadLocationException;
  16 import org.eclipse.jface.text.IDocument;
  17 import org.eclipse.jface.text.IRegion;
  18 import org.eclipse.jface.text.Position;
  19 import org.eclipse.jface.text.TextUtilities;
  20 import org.eclipse.jface.text.templates.Template;
  21 import org.eclipse.jface.text.templates.TemplateBuffer;
  22 import org.eclipse.jface.text.templates.TemplateContextType;
  23 import org.eclipse.jface.text.templates.TemplateException;
  24 import org.eclipse.jface.text.templates.TemplateTranslator;
  25
  26 import org.eclipse.jdt.core.ICompilationUnit;
  27 import org.eclipse.jdt.core.IJavaProject;
  28
  29 import org.eclipse.jdt.internal.corext.util.Strings;
  30
  31 import org.eclipse.jdt.ui.PreferenceConstants;
  32
  33 import org.eclipse.jdt.internal.ui.JavaPlugin;
  34
  35
  36 /**
  37  * A context for javadoc.
  38  */
  39 public class JavaDocContext extends CompilationUnitContext {
  40
  41         // tags
  42         private static final char HTML_TAG_BEGIN= '<';
  43         private static final char HTML_TAG_END= '>';
  44         private static final char JAVADOC_TAG_BEGIN= '@';
  45
  46         /**
  47          * Creates a javadoc template context.
  48          *
  49          * @param type the context type.
  50          * @param document the document.
  51          * @param completionOffset the completion offset within the document.
  52          * @param completionLength the completion length within the document.
  53          * @param compilationUnit the compilation unit (may be <code>null</code>).
  54          */
  55         public JavaDocContext(TemplateContextType type, IDocument document, int completionOffset, int completionLength, ICompilationUnit compilationUnit) {
  56                 super(type, document, completionOffset, completionLength, compilationUnit);
  57         }
  58
  59         /**
  60          * Creates a javadoc template context.
  61          *
  62          * @param type the context type.
  63          * @param document the document.
  64          * @param completionPosition the position defining the completion offset and length
  65          * @param compilationUnit the compilation unit (may be <code>null</code>).
  66          * @since 3.2
  67          */
  68         public JavaDocContext(TemplateContextType type, IDocument document, Position completionPosition, ICompilationUnit compilationUnit) {
  69                 super(type, document, completionPosition, compilationUnit);
  70         }
  71
  72         /*
  73          * @see TemplateContext#canEvaluate(Template templates)
  74          */
  75         @Override
  76         public boolean canEvaluate(Template template) {
  77                 String key= getKey();
  78
  79                 if (fForceEvaluation)
  80                         return true;
  81
  82                 return
  83                         template.matches(key, getContextType().getId()) &&
  84                         (key.length() != 0) && template.getName().toLowerCase().startsWith(key.toLowerCase());
  85         }
  86
  87         /*
  88          * @see DocumentTemplateContext#getStart()
  89          */
  90         @Override
  91         public int getStart() {
  92                 if (fIsManaged && getCompletionLength() > 0)
  93                         return super.getStart();
  94
  95                 try {
  96                         IDocument document= getDocument();
  97
  98                         if (getCompletionLength() == 0) {
  99                                 int start= getCompletionOffset();
 100
 101                                 if ((start != 0) && (document.getChar(start - 1) == HTML_TAG_END))
 102                                         start--;
 103
 104                                 while ((start != 0) && Character.isUnicodeIdentifierPart(document.getChar(start - 1)))
 105                                         start--;
 106
 107                                 if ((start != 0) && Character.isUnicodeIdentifierStart(document.getChar(start - 1)))
 108                                         start--;
 109
 110                                 // include html and javadoc tags
 111                                 if ((start != 0) && (
 112                                         (document.getChar(start - 1) == HTML_TAG_BEGIN) ||
 113                                         (document.getChar(start - 1) == JAVADOC_TAG_BEGIN)))
 114                                 {
 115                                         start--;
 116                                 }
 117
 118                                 return start;
 119
 120                         }
 121
 122                         int start= getCompletionOffset();
 123                         int end= getCompletionOffset() + getCompletionLength();
 124
 125                         while (start != 0 && Character.isUnicodeIdentifierPart(document.getChar(start - 1)))
 126                                 start--;
 127
 128                         while (start != end && Character.isWhitespace(document.getChar(start)))
 129                                 start++;
 130
 131                         if (start == end)
 132                                 start= getCompletionOffset();
 133
 134                         return start;
 135
 136
 137                 } catch (BadLocationException e) {
 138                         return getCompletionOffset();
 139                 }
 140         }
 141
 142         /*
 143          * @see org.eclipse.jdt.internal.corext.template.DocumentTemplateContext#getEnd()
 144          */
 145         @Override
 146         public int getEnd() {
 147
 148                 if (fIsManaged || getCompletionLength() == 0)
 149                         return super.getEnd();
 150
 151                 try {
 152                         IDocument document= getDocument();
 153
 154                         int start= getCompletionOffset();
 155                         int end= getCompletionOffset() + getCompletionLength();
 156
 157                         while (start != end && Character.isWhitespace(document.getChar(end - 1)))
 158                                 end--;
 159
 160                         return end;
 161
 162                 } catch (BadLocationException e) {
 163                         return super.getEnd();
 164                 }
 165         }
 166
 167         /*
 168          * @see org.eclipse.jdt.internal.corext.template.DocumentTemplateContext#getKey()
 169          */
 170         @Override
 171         public String getKey() {
 172
 173                 if (getCompletionLength() == 0)
 174                         return super.getKey();
 175
 176                 try {
 177                         IDocument document= getDocument();
 178
 179                         int start= getStart();
 180                         int end= getCompletionOffset();
 181                         return start <= end
 182                                 ? document.get(start, end - start)
 183                                 : ""; //$NON-NLS-1$
 184
 185                 } catch (BadLocationException e) {
 186                         return super.getKey();
 187                 }
 188         }
 189
 190         /*
 191          * @see TemplateContext#evaluate(Template)
 192          */
 193         @Override
 194         public TemplateBuffer evaluate(Template template) throws BadLocationException, TemplateException {
 195                 TemplateTranslator translator= new TemplateTranslator();
 196                 TemplateBuffer buffer= translator.translate(template);
 197
 198                 getContextType().resolve(buffer, this);
 199
 200                 IPreferenceStore prefs= JavaPlugin.getDefault().getPreferenceStore();
 201                 boolean useCodeFormatter= prefs.getBoolean(PreferenceConstants.TEMPLATES_USE_CODEFORMATTER);
 202
 203                 IJavaProject project= getJavaProject();
 204                 JavaFormatter formatter= new JavaFormatter(TextUtilities.getDefaultLineDelimiter(getDocument()), getIndentation(), useCodeFormatter, project);
 205                 formatter.format(buffer, this);
 206
 207                 return buffer;
 208         }
 209
 210         /**
 211          * Returns the indentation level at the position of code completion.
 212          *
 213          * @return the indentation level at the position of the code completion
 214          */
 215         private int getIndentation() {
 216                 int start= getStart();
 217                 IDocument document= getDocument();
 218                 try {
 219                         IRegion region= document.getLineInformationOfOffset(start);
 220                         String lineContent= document.get(region.getOffset(), region.getLength());
 221                         IJavaProject project= getJavaProject();
 222                         return Strings.computeIndentUnits(lineContent, project);
 223                 } catch (BadLocationException e) {
 224                         return 0;
 225                 }
 226         }
 227 }
 228