| /* |
| * 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.geronimo.javamail.store.nntp.newsrc; |
| |
| import java.io.BufferedReader; |
| import java.io.IOException; |
| import java.io.Writer; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.Map; |
| |
| /** |
| * Base class implementation of a standard news reader news rc file. This is |
| * used to track newsgroup subscriptions and SEEN flags for articles. This is an |
| * abstract class designed for subclasses to bridge to the physical store type |
| * used for the newsgroup information. |
| */ |
| public abstract class NNTPNewsrc { |
| |
| // the group information we've read from the news rc file. |
| Map groups = new HashMap(); |
| |
| // flag to let us know of we need to persist the newsrc file on close. |
| boolean dirty = false; |
| |
| /** |
| * Base class constructor for NNTPNewsrc items. Subclasses provide their own |
| * domain-specific intialization. |
| */ |
| protected NNTPNewsrc() { |
| } |
| |
| /** |
| * Load the data from the newsrc file and parse into an instore group |
| * database. |
| */ |
| public void load() { |
| BufferedReader in = null; |
| |
| try { |
| in = getInputReader(); |
| |
| String line = in.readLine(); |
| |
| while (line != null) { |
| // parse the line...this returns null if it's something |
| // unrecognized. |
| NNTPNewsrcGroup group = NNTPNewsrcGroup.parse(this, line); |
| // if it parsed ok, add it to the group list, and potentially to |
| // the subscribed list. |
| if (group != null) { |
| groups.put(group.getName(), group); |
| } |
| |
| line = in.readLine(); |
| } |
| |
| in.close(); |
| } catch (IOException e) { |
| // an IOException may mean that the file just doesn't exist, which |
| // is fine. We'll ignore and |
| // proceed with the information we have. |
| } finally { |
| if (in != null) { |
| try { |
| in.close(); |
| } catch (IOException e) { |
| // ignore |
| } |
| } |
| } |
| } |
| |
| /** |
| * Save the newsrc file data back to the original source file. |
| * |
| * @exception IOException |
| */ |
| public void save() throws IOException { |
| Writer out = getOutputWriter(); |
| |
| Iterator i = groups.values().iterator(); |
| |
| while (i.hasNext()) { |
| NNTPNewsrcGroup group = (NNTPNewsrcGroup) i.next(); |
| group.save(out); |
| } |
| |
| out.close(); |
| } |
| |
| /** |
| * Abstract open method intended for sub class initialization. The subclass |
| * is responsible for creating the BufferedReaded used to read the .newsrc |
| * file. |
| * |
| * @return A BufferedReader for reading the .newsrc file. |
| * @exception IOException |
| */ |
| abstract public BufferedReader getInputReader() throws IOException; |
| |
| /** |
| * Abstract open for output method intended for subclass implementation. The |
| * subclasses are reponsible for opening the output stream and creating an |
| * appropriate Writer for saving the .newsrc file. |
| * |
| * @return A Writer target at the .newsrc file save location. |
| * @exception IOException |
| */ |
| abstract public Writer getOutputWriter() throws IOException; |
| |
| /** |
| * Retrieve the newsrc group information for a named group. If the file does |
| * not currently include this group, an unsubscribed group will be added to |
| * the file. |
| * |
| * @param name |
| * The name of the target group. |
| * |
| * @return The NNTPNewsrcGroup item corresponding to this name. |
| */ |
| public NNTPNewsrcGroup getGroup(String name) { |
| NNTPNewsrcGroup group = (NNTPNewsrcGroup) groups.get(name); |
| // if we don't know about this, create a new one and add to the list. |
| // This |
| // will be an unsubscribed one. |
| if (group == null) { |
| group = new NNTPNewsrcGroup(this, name, null, false); |
| groups.put(name, group); |
| // we've added a group, so we need to resave |
| dirty = true; |
| } |
| return group; |
| } |
| |
| /** |
| * Mark this newsrc database as dirty. |
| */ |
| public void setDirty() { |
| dirty = true; |
| } |
| |
| /** |
| * Close the newsrc file, persisting it back to disk if the file has |
| * changed. |
| */ |
| public void close() { |
| if (dirty) { |
| try { |
| save(); |
| } catch (IOException e) { |
| // ignore |
| } |
| } |
| } |
| |
| /** |
| * Retrieve the current set of loaded groups. |
| * |
| * @return An iterator for traversing the group set. |
| */ |
| public Iterator getGroups() { |
| return groups.values().iterator(); |
| } |
| } |