base/runtime/org.argeo.eclipse.ui/src/main/java/org/argeo/eclipse/ui/AbstractTreeContentProvider.java

   1 /*
   2  * Copyright (C) 2007-2012 Argeo GmbH
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.argeo.eclipse.ui;
  17
  18 import org.eclipse.jface.viewers.ITreeContentProvider;
  19 import org.eclipse.jface.viewers.Viewer;
  20
  21 /**
  22  * Tree content provider dealing with tree objects and providing reasonable
  23  * defaults.
  24  */
  25 public abstract class AbstractTreeContentProvider implements
  26                 ITreeContentProvider {
  27
  28         /** Does nothing */
  29         public void dispose() {
  30         }
  31
  32         /** Does nothing */
  33         public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
  34         }
  35
  36         public Object[] getChildren(Object element) {
  37                 if (element instanceof TreeParent) {
  38                         return ((TreeParent) element).getChildren();
  39                 }
  40                 return new Object[0];
  41         }
  42
  43         public Object getParent(Object element) {
  44                 if (element instanceof TreeParent) {
  45                         return ((TreeParent) element).getParent();
  46                 }
  47                 return null;
  48         }
  49
  50         public boolean hasChildren(Object element) {
  51                 if (element instanceof TreeParent) {
  52                         return ((TreeParent) element).hasChildren();
  53                 }
  54                 return false;
  55         }
  56
  57 }