2009/05/20 - Apache Shale has been retired.

 /*

  * Licensed to the Apache Software Foundation (ASF) under one or more

  * contributor license agreements.  See the NOTICE file distributed with

  * this work for additional information regarding copyright ownership.

  * The ASF licenses this file to you 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 org.apache.shale.util;

 import java.beans.Beans;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.Collections;

 import java.util.Enumeration;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.List;

 import java.util.Locale;

 import java.util.Map;

 import java.util.MissingResourceException;

 import java.util.ResourceBundle;

 import java.util.Set;

 import javax.faces.component.UIViewRoot;

 import javax.faces.context.FacesContext;

 /**

  * <p>Utility class emulating the behavior of the standard JSF Core Library

  * tag <code>&lt;f:loadBundle&gt;</code>.  This class is designed to be used

  * as a managed bean, and exposes a <code>map</code> property containing the

  * messages in the resoruce bundle specified by the <code>basename</code>

  * property, localized for the <code>Locale</code> specified on the current

  * request.</p>

  *

  * <p>A typical use of this class would be to declare a managed bean like this:</p>

  * <pre>

  *    <managed-bean>

  *      <managed-bean-name>bundle</managed-bean-name>

  *      <managed-bean-class>

  *        org.apache.shale.util.LoadBundle

  *      </managed-bean-class>

  *      <managed-bean-scope>request</managed-bean-scope>

  *      <managed-property>

  *        <property-name>basename</property-name>

  *        <value>com.mycompany.mypackage.Bundle</value>

  *      </managed-property>

  *    </managed-bean>

  * </pre>

  *

  * <p>This will result in creation of a request scope object whose <code>map</code>

  * property will return a <code>Map</code> representing the localized messages for

  * the <code>com.mycompany.mypackage.Bundle</code> resource bundle.  You can look

  * up localized messages in this <code>Map</code> by evaluating a value binding

  * expression like this:</p>

  * <blockquote>

  *   <code>#{messages.['message.key']}</code>

  * </blockquote>

  * <p>where <code>message.key</code> is the key for which to retrieve a

  * localized message.</p>

  *

  * <p>(Since 1.0.1) <strong>IMPLEMENTATION NOTE</strong> - For backwards

  * compatibility in applications that utilized the 1.0.0 version of this

  * class, the following sort of expression resolves to the same value:</p>

  * <blockquote>

  *   <code>#{messages.map['message.key']}</code>

  * </blockquote>

  */

 public class LoadBundle {

    // ------------------------------------------------------------- Constructors

    /** Creates a new instance of LoadBundle. */

    public LoadBundle() {

         this(null);

    }

    /** <p>Creates a new instance of LoadBundle for the specified bundle.</p>

     *

     * @param basename Base resource bundle name for this <code>LoadBundle</code>

     */

    public LoadBundle(String basename) {

        this.basename = basename;

    }

    // --------------------------------------------------------- Static Variables

    /**

     * <p>The default <code>Locale</code> for this application.</p>

     */

    private static final Locale defaultLocale = Locale.getDefault();

    // --------------------------------------------------------------- Properties

    /**

     * <p>The base resource bundle name for this <code>LoadBundle</code> instance.</p>

     */

    private String basename = null;

    /**

     * <p>Return the base resource bundle name for this <code>LoadBundle</code>

     * instance.</p>

     */

    public String getBasename() {

        return this.basename;

    }

    /**

     * <p>Set the base resource bundle name for this <code>LoadBundle</code>

     * instance.</p>

     *

     * @param basename The new base resource bundle name

     */

    public void setBasename(String basename) {

        this.basename = basename;

    }

    // ----------------------------------------------------------- Public Methods

    /**

     * <p>Return a <code>Map</code> whose keys and values represent the content

     * of the application resource bundle specified by the <code>basename</code>

     * property, localized for the <code>Locale</code> stored in the

     * <code>UIViewRoot</code> for the current request.</p>

     *

     * @exception IllegalStateException if we are not inside a Faces request,

     *  or if there is not a current view root with a valid locale

     */

    public Map getMap() throws IllegalStateException {

        // Validate our current state

        if (basename == null) {

            if (Beans.isDesignTime()) {

                return Collections.EMPTY_MAP;

            }

            throw new IllegalStateException("The 'basename' property cannot be null"); // FIXME - i18n

        }

        FacesContext context = FacesContext.getCurrentInstance();

        UIViewRoot root = null;

        Locale locale = null;

        if (context != null) {

            root = context.getViewRoot();

        }

        if (root != null) {

            locale = root.getLocale();

        }

        if (locale == null) {

            throw new IllegalStateException("Cannot retrieve locale-specific map if there " +

                    "is not a current Faces request, containing a valid view root, with" +

                    "a Locale instance inside.");

        }

        // Look up the requested resource bundle

        final ResourceBundle bundle = getBundle(basename, locale);

        if (bundle == null) {

            throw new IllegalArgumentException

              ("No resource bundle found for base name '" + basename + "' and locale '" + locale + "'"); // FIXME - i18n

        }

        // Construct and return an immutable Map representing these contents

        Map map = new Map() {

            public void clear() {

                throw new UnsupportedOperationException();

            }

            public boolean containsKey(Object key) {

                boolean result = false;

                if (key != null) {

                    result = bundle.getObject(key.toString()) != null;

                }

                return result;

            }

            public boolean containsValue(Object value) {

                Enumeration keys = bundle.getKeys();

                while (keys.hasMoreElements()) {

                    Object val = bundle.getObject(keys.nextElement().toString());

                    if ((val != null) && val.equals(value)) {

                        return true;

                    }

                }

                return false;

            }

            public Set entrySet() {

                Map map = new HashMap();

                Enumeration keys = bundle.getKeys();

                while (keys.hasMoreElements()) {

                    String key = keys.nextElement().toString();

                    Object value = bundle.getObject(key);

                    map.put(key, value);

                }

                return map.entrySet();

            }

            public boolean equals(Object o) {

                if ((o == null) || !(o instanceof Map)) {

                    return false;

                }

                return entrySet().equals(((Map) o).entrySet());

            }

            public Object get(Object key) {

                if (key == null) {

                    return null;

                }

                try {

                    return bundle.getObject(key.toString());

                } catch (MissingResourceException e) {

                    return "???" + key.toString() + "???";

                }

            }

            public int hashCode() {

                return bundle.hashCode();

            }

            public boolean isEmpty() {

                Enumeration keys = bundle.getKeys();

                while (keys.hasMoreElements()) {

                    return false;

                }

                return true;

            }

            public Set keySet() {

                Set set = new HashSet();

                Enumeration keys = bundle.getKeys();

                while (keys.hasMoreElements()) {

                    set.add(keys.nextElement());

                }

                return set;

            }

            public Object put(Object key, Object value) {

                throw new UnsupportedOperationException();

            }

            public void putAll(Map map) {

                throw new UnsupportedOperationException();

            }

            public Object remove(Object key) {

                throw new UnsupportedOperationException();

            }

            public int size() {

                int size = 0;

                Enumeration keys = bundle.getKeys();

                while (keys.hasMoreElements()) {

                    keys.nextElement();

                    size++;

                }

                return size;

            }

            public Collection values() {

                List list = new ArrayList();

                Enumeration keys = bundle.getKeys();

                while (keys.hasMoreElements()) {

                    String key = keys.nextElement().toString();

                    list.add(bundle.getObject(key));

                }

                return list;

            }

        };

        return map;

    }

     // --------------------------------------------------------- Private Methods

     /**

      * <p>Return the localized <code>ResourceBundle</code> for the specified

      * <code>Locale</code>.</p>

      *

      * @param basename Base name of the resource bundle to return

      * @param locale Locale used to select the appropriate resource bundle

      */

     private ResourceBundle getBundle(String basename, Locale locale) {

         assert basename != null;

         assert locale != null;

         ClassLoader rbcl = Thread.currentThread().getContextClassLoader();

         if (rbcl == null) {

             rbcl = this.getClass().getClassLoader();

         }

         try {

             return ResourceBundle.getBundle(basename, locale, rbcl);

         } catch (MissingResourceException e) {

             return ResourceBundle.getBundle(basename, defaultLocale, rbcl);

         }

     }

 }