net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/text/java/hover/BestMatchHover.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2003 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.java.hover;
  12
  13 import java.util.ArrayList;
  14 import java.util.Iterator;
  15 import java.util.List;
  16
  17 import net.sourceforge.phpdt.ui.PreferenceConstants;
  18 import net.sourceforge.phpdt.ui.text.java.hover.IJavaEditorTextHover;
  19 import net.sourceforge.phpeclipse.PHPeclipsePlugin;
  20
  21 import org.eclipse.jface.text.IInformationControlCreator;
  22 import org.eclipse.jface.text.IRegion;
  23 import org.eclipse.jface.text.ITextHover;
  24 import org.eclipse.jface.text.ITextHoverExtension;
  25 import org.eclipse.jface.text.ITextViewer;
  26 import org.eclipse.jface.text.information.IInformationProviderExtension2;
  27 import org.eclipse.ui.IEditorPart;
  28
  29
  30 /**
  31  * Caution: this implementation is a layer breaker and contains some "shortcuts"
  32  */
  33 public class BestMatchHover extends AbstractJavaEditorTextHover implements ITextHoverExtension, IInformationProviderExtension2 {
  34
  35         private List fTextHoverSpecifications;
  36         private List fInstantiatedTextHovers;
  37         private ITextHover fBestHover;
  38
  39         public BestMatchHover() {
  40                 installTextHovers();
  41         }
  42
  43         public BestMatchHover(IEditorPart editor) {
  44                 this();
  45                 setEditor(editor);
  46         }
  47
  48         /**
  49          * Installs all text hovers.
  50          */
  51         private void installTextHovers() {
  52
  53                 // initialize lists - indicates that the initialization happened
  54                 fTextHoverSpecifications= new ArrayList(2);
  55                 fInstantiatedTextHovers= new ArrayList(2);
  56
  57                 // populate list
  58                 JavaEditorTextHoverDescriptor[] hoverDescs= PHPeclipsePlugin.getDefault().getJavaEditorTextHoverDescriptors();
  59                 for (int i= 0; i < hoverDescs.length; i++) {
  60                         // ensure that we don't add ourselves to the list
  61                         if (!PreferenceConstants.ID_BESTMATCH_HOVER.equals(hoverDescs[i].getId()))
  62                                 fTextHoverSpecifications.add(hoverDescs[i]);
  63                 }
  64         }
  65
  66         private void checkTextHovers() {
  67                 if (fTextHoverSpecifications.size() == 0)
  68                         return;
  69
  70                 for (Iterator iterator= new ArrayList(fTextHoverSpecifications).iterator(); iterator.hasNext(); ) {
  71                         JavaEditorTextHoverDescriptor spec= (JavaEditorTextHoverDescriptor) iterator.next();
  72
  73                         IJavaEditorTextHover hover= spec.createTextHover();
  74                         if (hover != null) {
  75                                 hover.setEditor(getEditor());
  76                                 addTextHover(hover);
  77                                 fTextHoverSpecifications.remove(spec);
  78                         }
  79                 }
  80         }
  81
  82         protected void addTextHover(ITextHover hover) {
  83                 if (!fInstantiatedTextHovers.contains(hover))
  84                         fInstantiatedTextHovers.add(hover);
  85         }
  86
  87         /*
  88          * @see ITextHover#getHoverInfo(ITextViewer, IRegion)
  89          */
  90         public String getHoverInfo(ITextViewer textViewer, IRegion hoverRegion) {
  91
  92                 checkTextHovers();
  93                 fBestHover= null;
  94
  95                 if (fInstantiatedTextHovers == null)
  96                         return null;
  97
  98                 for (Iterator iterator= fInstantiatedTextHovers.iterator(); iterator.hasNext(); ) {
  99                         ITextHover hover= (ITextHover)iterator.next();
 100
 101                         String s= hover.getHoverInfo(textViewer, hoverRegion);
 102                         if (s != null && s.trim().length() > 0) {
 103                                 fBestHover= hover;
 104                                 return s;
 105                         }
 106                 }
 107
 108                 return null;
 109         }
 110
 111         /*
 112          * @see org.eclipse.jface.text.ITextHoverExtension#getInformationControlCreator()
 113          * @since 3.0
 114          */
 115         public IInformationControlCreator getInformationControlCreator() {
 116                 if (fBestHover instanceof ITextHoverExtension)
 117                         return ((ITextHoverExtension)fBestHover).getInformationControlCreator();
 118
 119                 return null;
 120         }
 121
 122         /*
 123          * @see org.eclipse.jface.text.information.IInformationProviderExtension2#getInformationPresenterControlCreator()
 124          * @since 3.0
 125          */
 126         public IInformationControlCreator getInformationPresenterControlCreator() {
 127                 if (fBestHover instanceof IInformationProviderExtension2)
 128                         return ((IInformationProviderExtension2)fBestHover).getInformationPresenterControlCreator();
 129
 130                 return null;
 131         }
 132 }