filterbeaninfo.java

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/*
 * Copyright 2003-2005 the original author or authors.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 */
package com.jdon.jivejdon.model.message.output.beanutil;


import java.beans.BeanDescriptor;
import java.beans.BeanInfo;
import java.beans.EventSetDescriptor;
import java.beans.IntrospectionException;
import java.beans.MethodDescriptor;
import java.beans.PropertyDescriptor;
import java.util.Enumeration;
import java.util.Locale;
import java.util.ResourceBundle;

/**
 * An abstract BeanInfo implementation that automatically constructs
 * PropertyDescriptors and handles i18n through ResourceBundles.
 */
public abstract class FilterBeanInfo implements BeanInfo {

    private ResourceBundle bundle;

    public FilterBeanInfo() {
        //Get the locale that should be used, then load the resource bundle.
        Locale currentLocale = Locale.US;
        try {
            bundle = ResourceBundle.getBundle("bean_" + getName(),
                    currentLocale);
        }
        catch (Exception e) {
            // Ignore any exception when trying to load bundle.
        }
    }

    /**
     * Returns the names of the properties of the bean that should be exposed.
     *
     * @return the names of the properties that should be exposed.
     */
    public abstract String [] getPropertyNames();

    /**
     * Returns the bean Class.
     *
     * @return the Class of the JavaBean that the BeanInfo is for.
     */
    public abstract Class getBeanClass();

    /**
     * Returns the name of the class that the bean info applies to (which
     * corresponds to the resource bundle that will be loaded). For example,
     * for the class <tt>com.foo.ExampleClass</tt>, the name would be
     * <tt>ExampleClass</tt>.
     *
     * @return the name of the JavaBean that the BeanInfo is for.
     */
    public abstract String getName();

    //FROM THE BEANINFO INTERFACE//

    public BeanDescriptor getBeanDescriptor() {
        BeanDescriptor descriptor = new BeanDescriptor(getBeanClass());
        try {
            // Attempt to load the displayName and shortDescription explicitly.
            String displayName = bundle.getString("displayName");
            if (displayName != null) {
                descriptor.setDisplayName(displayName);
            }
            String shortDescription = bundle.getString("shortDescription");
            if (shortDescription != null) {
                descriptor.setShortDescription(shortDescription);
            }
            // Add any other properties that are specified.
            Enumeration em = bundle.getKeys();
            while (em.hasMoreElements()) {
                String key = (String)em.nextElement();
                String value = bundle.getString(key);
                if (value != null) {
                    descriptor.setValue(key, value);
                }
            }
        }
        catch (Exception e) {
            // Ignore any exceptions. We may get some if we try to load a
            // a property that doesn't appear in the resource bundle.
        }
        return descriptor;
    }

    public PropertyDescriptor[] getPropertyDescriptors()  {
        Class beanClass = getBeanClass();
        String [] properties = getPropertyNames();

        PropertyDescriptor [] descriptors = new PropertyDescriptor[properties.length];
        try {
            // For each property, create a property descriptor and set the
            // name and description using the localized data.
            for (int i=0; i<descriptors.length; i++) {
                PropertyDescriptor newDescriptor =
                    new PropertyDescriptor(properties[i], beanClass);
                if (bundle != null) {
                    newDescriptor.setDisplayName(
                        bundle.getString(properties[i] + ".displayName")
                    );
                    newDescriptor.setShortDescription(
                        bundle.getString(properties[i] + ".shortDescription")
                    );
                }
                descriptors[i] = newDescriptor;
            }
            return descriptors;
        }
        catch (IntrospectionException ie) {
            ie.printStackTrace();
            throw new Error(ie.toString());
        }
    }

    public int getDefaultPropertyIndex() {
	return -1;
    }

    public EventSetDescriptor[] getEventSetDescriptors() {
	return null;
    }

    public int getDefaultEventIndex() {
	return -1;
    }

    public MethodDescriptor[] getMethodDescriptors() {
	return null;
    }

    public BeanInfo[] getAdditionalBeanInfo() {
	return null;
    }

    public java.awt.Image getIcon(int iconKind) {
	return null;
    }
    
  
}