aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: package javax.activation;
aoqi@0: 
aoqi@0: import java.util.Map;
aoqi@0: import java.util.WeakHashMap;
aoqi@0: 
aoqi@0: 
aoqi@0: /**
aoqi@0:  * The CommandMap class provides an interface to a registry of
aoqi@0:  * command objects available in the system.
aoqi@0:  * Developers are expected to either use the CommandMap
aoqi@0:  * implementation included with this package (MailcapCommandMap) or
aoqi@0:  * develop their own. Note that some of the methods in this class are
aoqi@0:  * abstract.
aoqi@0:  *
aoqi@0:  * @since 1.6
aoqi@0:  */
aoqi@0: public abstract class CommandMap {
aoqi@0:     private static CommandMap defaultCommandMap = null;
aoqi@0:     private static Map<ClassLoader,CommandMap> map =
aoqi@0:                                 new WeakHashMap<ClassLoader,CommandMap>();
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get the default CommandMap.
aoqi@0:      * <p>
aoqi@0:      *
aoqi@0:      * <ul>
aoqi@0:      * <li> In cases where a CommandMap instance has been previously set
aoqi@0:      *      to some value (via <i>setDefaultCommandMap</i>)
aoqi@0:      *  return the CommandMap.
aoqi@0:      * <li>
aoqi@0:      *  In cases where no CommandMap has been set, the CommandMap
aoqi@0:      *       creates an instance of <code>MailcapCommandMap</code> and
aoqi@0:      *       set that to the default, returning its value.
aoqi@0:      *
aoqi@0:      * </ul>
aoqi@0:      *
aoqi@0:      * @return the CommandMap
aoqi@0:      */
aoqi@0:     public static synchronized CommandMap getDefaultCommandMap() {
aoqi@0:         if (defaultCommandMap != null)
aoqi@0:             return defaultCommandMap;
aoqi@0: 
aoqi@0:         // fetch per-thread-context-class-loader default
aoqi@0:         ClassLoader tccl = SecuritySupport.getContextClassLoader();
aoqi@0:         CommandMap def = map.get(tccl);
aoqi@0:         if (def == null) {
aoqi@0:             def = new MailcapCommandMap();
aoqi@0:             map.put(tccl, def);
aoqi@0:         }
aoqi@0:         return def;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Set the default CommandMap. Reset the CommandMap to the default by
aoqi@0:      * calling this method with <code>null</code>.
aoqi@0:      *
aoqi@0:      * @param commandMap The new default CommandMap.
aoqi@0:      * @exception SecurityException if the caller doesn't have permission
aoqi@0:      *                                  to change the default
aoqi@0:      */
aoqi@0:     public static synchronized void setDefaultCommandMap(CommandMap commandMap) {
aoqi@0:         SecurityManager security = System.getSecurityManager();
aoqi@0:         if (security != null) {
aoqi@0:             try {
aoqi@0:                 // if it's ok with the SecurityManager, it's ok with me...
aoqi@0:                 security.checkSetFactory();
aoqi@0:             } catch (SecurityException ex) {
aoqi@0:                 // otherwise, we also allow it if this code and the
aoqi@0:                 // factory come from the same (non-system) class loader (e.g.,
aoqi@0:                 // the JAF classes were loaded with the applet classes).
aoqi@0:                 if (CommandMap.class.getClassLoader() == null ||
aoqi@0:                     CommandMap.class.getClassLoader() !=
aoqi@0:                             commandMap.getClass().getClassLoader())
aoqi@0:                     throw ex;
aoqi@0:             }
aoqi@0:         }
aoqi@0:         // remove any per-thread-context-class-loader CommandMap
aoqi@0:         map.remove(SecuritySupport.getContextClassLoader());
aoqi@0:         defaultCommandMap = commandMap;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get the preferred command list from a MIME Type. The actual semantics
aoqi@0:      * are determined by the implementation of the CommandMap.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @return the CommandInfo classes that represent the command Beans.
aoqi@0:      */
aoqi@0:     abstract public  CommandInfo[] getPreferredCommands(String mimeType);
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get the preferred command list from a MIME Type. The actual semantics
aoqi@0:      * are determined by the implementation of the CommandMap. <p>
aoqi@0:      *
aoqi@0:      * The <code>DataSource</code> provides extra information, such as
aoqi@0:      * the file name, that a CommandMap implementation may use to further
aoqi@0:      * refine the list of commands that are returned.  The implementation
aoqi@0:      * in this class simply calls the <code>getPreferredCommands</code>
aoqi@0:      * method that ignores this argument.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @param ds        a DataSource for the data
aoqi@0:      * @return the CommandInfo classes that represent the command Beans.
aoqi@0:      * @since   JAF 1.1
aoqi@0:      */
aoqi@0:     public CommandInfo[] getPreferredCommands(String mimeType, DataSource ds) {
aoqi@0:         return getPreferredCommands(mimeType);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get all the available commands for this type. This method
aoqi@0:      * should return all the possible commands for this MIME type.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @return the CommandInfo objects representing all the commands.
aoqi@0:      */
aoqi@0:     abstract public CommandInfo[] getAllCommands(String mimeType);
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get all the available commands for this type. This method
aoqi@0:      * should return all the possible commands for this MIME type. <p>
aoqi@0:      *
aoqi@0:      * The <code>DataSource</code> provides extra information, such as
aoqi@0:      * the file name, that a CommandMap implementation may use to further
aoqi@0:      * refine the list of commands that are returned.  The implementation
aoqi@0:      * in this class simply calls the <code>getAllCommands</code>
aoqi@0:      * method that ignores this argument.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @param ds        a DataSource for the data
aoqi@0:      * @return the CommandInfo objects representing all the commands.
aoqi@0:      * @since   JAF 1.1
aoqi@0:      */
aoqi@0:     public CommandInfo[] getAllCommands(String mimeType, DataSource ds) {
aoqi@0:         return getAllCommands(mimeType);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get the default command corresponding to the MIME type.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @param cmdName   the command name
aoqi@0:      * @return the CommandInfo corresponding to the command.
aoqi@0:      */
aoqi@0:     abstract public CommandInfo getCommand(String mimeType, String cmdName);
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get the default command corresponding to the MIME type. <p>
aoqi@0:      *
aoqi@0:      * The <code>DataSource</code> provides extra information, such as
aoqi@0:      * the file name, that a CommandMap implementation may use to further
aoqi@0:      * refine the command that is chosen.  The implementation
aoqi@0:      * in this class simply calls the <code>getCommand</code>
aoqi@0:      * method that ignores this argument.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @param cmdName   the command name
aoqi@0:      * @param ds        a DataSource for the data
aoqi@0:      * @return the CommandInfo corresponding to the command.
aoqi@0:      * @since   JAF 1.1
aoqi@0:      */
aoqi@0:     public CommandInfo getCommand(String mimeType, String cmdName,
aoqi@0:                                 DataSource ds) {
aoqi@0:         return getCommand(mimeType, cmdName);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Locate a DataContentHandler that corresponds to the MIME type.
aoqi@0:      * The mechanism and semantics for determining this are determined
aoqi@0:      * by the implementation of the particular CommandMap.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @return          the DataContentHandler for the MIME type
aoqi@0:      */
aoqi@0:     abstract public DataContentHandler createDataContentHandler(String
aoqi@0:                                                                 mimeType);
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Locate a DataContentHandler that corresponds to the MIME type.
aoqi@0:      * The mechanism and semantics for determining this are determined
aoqi@0:      * by the implementation of the particular CommandMap. <p>
aoqi@0:      *
aoqi@0:      * The <code>DataSource</code> provides extra information, such as
aoqi@0:      * the file name, that a CommandMap implementation may use to further
aoqi@0:      * refine the choice of DataContentHandler.  The implementation
aoqi@0:      * in this class simply calls the <code>createDataContentHandler</code>
aoqi@0:      * method that ignores this argument.
aoqi@0:      *
aoqi@0:      * @param mimeType  the MIME type
aoqi@0:      * @param ds        a DataSource for the data
aoqi@0:      * @return          the DataContentHandler for the MIME type
aoqi@0:      * @since   JAF 1.1
aoqi@0:      */
aoqi@0:     public DataContentHandler createDataContentHandler(String mimeType,
aoqi@0:                                 DataSource ds) {
aoqi@0:         return createDataContentHandler(mimeType);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get all the MIME types known to this command map.
aoqi@0:      * If the command map doesn't support this operation,
aoqi@0:      * null is returned.
aoqi@0:      *
aoqi@0:      * @return          array of MIME types as strings, or null if not supported
aoqi@0:      * @since   JAF 1.1
aoqi@0:      */
aoqi@0:     public String[] getMimeTypes() {
aoqi@0:         return null;
aoqi@0:     }
aoqi@0: }