1 /*
   2  * Copyright (c) 1996, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.beans;
  27 
  28 /**
  29  * This is a support class to make it easier for people to provide
  30  * BeanInfo classes.
  31  * <p>
  32  * It defaults to providing "noop" information, and can be selectively
  33  * overriden to provide more explicit information on chosen topics.
  34  * When the introspector sees the "noop" values, it will apply low
  35  * level introspection and design patterns to automatically analyze
  36  * the target bean.
  37  */
  38 
  39 public class SimpleBeanInfo implements BeanInfo {
  40 
  41     /**
  42      * Deny knowledge about the class and customizer of the bean.
  43      * You can override this if you wish to provide explicit info.
  44      */
  45     public BeanDescriptor getBeanDescriptor() {
  46         return null;
  47     }
  48 
  49     /**
  50      * Deny knowledge of properties. You can override this
  51      * if you wish to provide explicit property info.
  52      */
  53     public PropertyDescriptor[] getPropertyDescriptors() {
  54         return null;
  55     }
  56 
  57     /**
  58      * Deny knowledge of a default property. You can override this
  59      * if you wish to define a default property for the bean.
  60      */
  61     public int getDefaultPropertyIndex() {
  62         return -1;
  63     }
  64 
  65     /**
  66      * Deny knowledge of event sets. You can override this
  67      * if you wish to provide explicit event set info.
  68      */
  69     public EventSetDescriptor[] getEventSetDescriptors() {
  70         return null;
  71     }
  72 
  73     /**
  74      * Deny knowledge of a default event. You can override this
  75      * if you wish to define a default event for the bean.
  76      */
  77     public int getDefaultEventIndex() {
  78         return -1;
  79     }
  80 
  81     /**
  82      * Deny knowledge of methods. You can override this
  83      * if you wish to provide explicit method info.
  84      */
  85     public MethodDescriptor[] getMethodDescriptors() {
  86         return null;
  87     }
  88 
  89     /**
  90      * Claim there are no other relevant BeanInfo objects.  You
  91      * may override this if you want to (for example) return a
  92      * BeanInfo for a base class.
  93      */
  94     public BeanInfo[] getAdditionalBeanInfo() {
  95         return null;
  96     }
  97 
  98     /**
  99      * Claim there are no icons available.  You can override
 100      * this if you want to provide icons for your bean.
 101      */
 102     public java.awt.Image getIcon(int iconKind) {
 103         return null;
 104     }
 105 
 106     /**
 107      * This is a utility method to help in loading icon images.
 108      * It takes the name of a resource file associated with the
 109      * current object's class file and loads an image object
 110      * from that file.  Typically images will be GIFs.
 111      *
 112      * @param resourceName  A pathname relative to the directory
 113      *          holding the class file of the current class.  For example,
 114      *          "wombat.gif".
 115      * @return  an image object.  May be null if the load failed.
 116      */
 117     public java.awt.Image loadImage(final String resourceName) {
 118         try {
 119             final Class<?> c = getClass();
 120             java.awt.image.ImageProducer ip = (java.awt.image.ImageProducer)
 121                 java.security.AccessController.doPrivileged(
 122                 new java.security.PrivilegedAction<Object>() {
 123                     public Object run() {
 124                         java.net.URL url;
 125                         if ((url = c.getResource(resourceName)) == null) {
 126                             return null;
 127                         } else {
 128                             try {
 129                                 return url.getContent();
 130                             } catch (java.io.IOException ioe) {
 131                                 return null;
 132                             }
 133                         }
 134                     }
 135             });
 136 
 137             if (ip == null)
 138                 return null;
 139             java.awt.Toolkit tk = java.awt.Toolkit.getDefaultToolkit();
 140             return tk.createImage(ip);
 141         } catch (Exception ex) {
 142             return null;
 143         }
 144     }
 145 
 146 }