bundles/org.simantics.message.ui/src/org/simantics/message/ui/AbstractEntry.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
   3  * in Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.message.ui;
  13
  14 import java.io.PrintWriter;
  15 import java.util.ArrayList;
  16 import java.util.List;
  17
  18 import org.eclipse.core.runtime.PlatformObject;
  19 import org.eclipse.jface.resource.ImageDescriptor;
  20 import org.eclipse.ui.model.IWorkbenchAdapter;
  21
  22 /**
  23  * Everything that appears in LogView is Abstract Entry. It provides composite pattern.
  24  */
  25 public abstract class AbstractEntry extends PlatformObject implements IWorkbenchAdapter {
  26
  27         /**
  28          * The collection of direct children of this entry
  29          */
  30         private List<Object> children = new ArrayList<Object>();
  31         protected Object parent;
  32
  33         /**
  34          * Adds the specified child entry to the listing of children.
  35          * If the specified child is <code>null</code>, no work is done
  36          *
  37          * @param child
  38          */
  39         public void addChild(AbstractEntry child) {
  40                 if (child != null) {
  41                         children.add(0, child);
  42                         child.setParent(this);
  43                 }
  44         }
  45
  46         /**
  47          * @see IWorkbenchAdapter#getChildren(Object)
  48          */
  49         public Object[] getChildren(Object parent) {
  50                 return children.toArray();
  51         }
  52
  53         /**
  54          * @return true if this entry has children, false otherwise
  55          */
  56         public boolean hasChildren() {
  57                 return children.size() > 0;
  58         }
  59
  60         /**
  61          * @return the size of the child array
  62          *
  63          * TODO rename to getChildCount(), or something more meaningful
  64          */
  65         public int size() {
  66                 return children.size();
  67         }
  68
  69         /**
  70          * @see IWorkbenchAdapter#getImageDescriptor(Object)
  71          */
  72         public ImageDescriptor getImageDescriptor(Object object) {
  73                 return null;
  74         }
  75
  76         /**
  77          * @see IWorkbenchAdapter#getLabel(Object)
  78          */
  79         public String getLabel(Object o) {
  80                 return null;
  81         }
  82
  83         /**
  84          * @see IWorkbenchAdapter#getParent(Object)
  85          */
  86         public Object getParent(Object o) {
  87                 return parent;
  88         }
  89
  90         /**
  91          * Sets the parent of this entry
  92          * @param parent
  93          */
  94         public void setParent(AbstractEntry parent) {
  95                 this.parent = parent;
  96         }
  97
  98         /**
  99          * removes all of the children specified in the given listing
 100          *
 101          * @param list the list of children to remove
 102          */
 103         public void removeChildren(List<?> list) {
 104                 children.removeAll(list);
 105         }
 106
 107         /**
 108          * Removes all of the children from this entry
 109          */
 110         public void removeAllChildren() {
 111                 children.clear();
 112         }
 113
 114         /**
 115          * Writes this entry information into the given {@link PrintWriter}
 116          *
 117          * @param writer
 118          */
 119         public abstract void write(PrintWriter writer);
 120 }