Store.java revision 8664ecf1817e9965f9910dd12f6115ef4aaa8f2a
1/* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package com.android.email.mail; 18 19import com.android.email.Email; 20import com.android.email.R; 21 22import org.xmlpull.v1.XmlPullParserException; 23 24import android.content.Context; 25import android.content.res.XmlResourceParser; 26import android.util.Log; 27 28import java.io.IOException; 29 30/** 31 * Store is the access point for an email message store. It's location can be 32 * local or remote and no specific protocol is defined. Store is intended to 33 * loosely model in combination the JavaMail classes javax.mail.Store and 34 * javax.mail.Folder along with some additional functionality to improve 35 * performance on mobile devices. Implementations of this class should focus on 36 * making as few network connections as possible. 37 */ 38public abstract class Store { 39 40 /** 41 * String constants for known store schemes. 42 */ 43 public static final String STORE_SCHEME_IMAP = "imap"; 44 public static final String STORE_SCHEME_POP3 = "pop3"; 45 public static final String STORE_SCHEME_LOCAL = "local"; 46 47 /** 48 * A global suggestion to Store implementors on how much of the body 49 * should be returned on FetchProfile.Item.BODY_SANE requests. 50 */ 51 public static final int FETCH_BODY_SANE_SUGGESTED_SIZE = (50 * 1024); 52 53 private static java.util.HashMap<String, Store> mStores = 54 new java.util.HashMap<String, Store>(); 55 56 /** 57 * Static named constructor. It should be overrode by extending class. 58 * Because this method will be called through reflection, it can not be protected. 59 */ 60 public static Store newInstance(String uri, Context context) 61 throws MessagingException { 62 throw new MessagingException("Store.newInstance: Unknown scheme in " + uri); 63 } 64 65 private static Store instantiateStore(String className, String uri, Context context) 66 throws MessagingException { 67 Object o = null; 68 try { 69 Class<?> c = Class.forName(className); 70 // and invoke "newInstance" class method and instantiate store object. 71 java.lang.reflect.Method m = 72 c.getMethod("newInstance", String.class, Context.class); 73 o = m.invoke(null, uri, context); 74 } catch (Exception e) { 75 Log.d(Email.LOG_TAG, String.format( 76 "exception %s invoking %s.newInstance.(String, Context) method for %s", 77 e.toString(), className, uri)); 78 throw new MessagingException("can not instantiate Store object for " + uri); 79 } 80 if (!(o instanceof Store)) { 81 throw new MessagingException( 82 uri + ": " + className + " create incompatible object"); 83 } 84 return (Store) o; 85 } 86 87 /** 88 * Look up descriptive information about a particular type of store. 89 */ 90 public static class StoreInfo { 91 public String mScheme; 92 public String mClassName; 93 public boolean mPushSupported = false; 94 95 public static StoreInfo getStoreInfo(String scheme, Context context) { 96 StoreInfo result = getStoreInfo(R.xml.stores_product, scheme, context); 97 if (result == null) { 98 result = getStoreInfo(R.xml.stores, scheme, context); 99 } 100 return result; 101 } 102 103 public static StoreInfo getStoreInfo(int resourceId, String scheme, Context context) { 104 try { 105 XmlResourceParser xml = context.getResources().getXml(resourceId); 106 int xmlEventType; 107 // walk through stores.xml file. 108 while ((xmlEventType = xml.next()) != XmlResourceParser.END_DOCUMENT) { 109 if (xmlEventType == XmlResourceParser.START_TAG && 110 "store".equals(xml.getName())) { 111 String xmlScheme = xml.getAttributeValue(null, "scheme"); 112 if (scheme.startsWith(xmlScheme)) { 113 StoreInfo result = new StoreInfo(); 114 result.mScheme = scheme; 115 result.mClassName = xml.getAttributeValue(null, "class"); 116 result.mPushSupported = xml.getAttributeBooleanValue( 117 null, "push", false); 118 return result; 119 } 120 } 121 } 122 } catch (XmlPullParserException e) { 123 // ignore 124 } catch (IOException e) { 125 // ignore 126 } 127 return null; 128 } 129 } 130 131 /** 132 * Get an instance of a mail store. The URI is parsed as a standard URI and 133 * the scheme is used to determine which protocol will be used. 134 * 135 * Although the URI format is somewhat protocol-specific, we use the following 136 * guidelines wherever possible: 137 * 138 * scheme [+ security [+]] :// username : password @ host [ / resource ] 139 * 140 * Typical schemes include imap, pop3, local, eas. 141 * Typical security models include SSL or TLS. 142 * A + after the security identifier indicates "required". 143 * 144 * Username, password, and host are as expected. 145 * Resource is protocol specific. For example, IMAP uses it as the path prefix. EAS uses it 146 * as the domain. 147 * 148 * @param uri The URI of the store. 149 * @return an initialized store of the appropriate class 150 * @throws MessagingException 151 */ 152 public synchronized static Store getInstance(String uri, Context context) 153 throws MessagingException { 154 Store store = mStores.get(uri); 155 if (store == null) { 156 StoreInfo info = StoreInfo.getStoreInfo(uri, context); 157 if (info != null) { 158 store = instantiateStore(info.mClassName, uri, context); 159 } 160 161 if (store != null) { 162 mStores.put(uri, store); 163 } 164 } 165 166 if (store == null) { 167 throw new MessagingException("Unable to locate an applicable Store for " + uri); 168 } 169 170 return store; 171 } 172 173 /** 174 * Get class of SettingActivity for this Store class. 175 * @return Activity class that has class method actionEditIncomingSettings(). 176 */ 177 public Class<? extends android.app.Activity> getSettingActivityClass() { 178 // default SettingActivity class 179 return com.android.email.activity.setup.AccountSetupIncoming.class; 180 } 181 182 public abstract Folder getFolder(String name) throws MessagingException; 183 184 public abstract Folder[] getPersonalNamespaces() throws MessagingException; 185 186 public abstract void checkSettings() throws MessagingException; 187 188 /** 189 * Enable or disable push mode delivery for a given Store. 190 * 191 * <p>For protocols that do not support push mode, be sure that push="true" is not 192 * set by the stores.xml definition file(s). This function need not be implemented. 193 * 194 * <p>For protocols that do support push mode, this will be called at startup (boot) time 195 * so that the Store can launch its own underlying connection service. It will also be called 196 * any time the user changes the settings for the account (because the user may switch back 197 * to polling mode (or disable checking completely). 198 * 199 * <p>This API will be called repeatedly, even after push mode has already been started or 200 * stopped. Stores that support push mode should return quickly if the configuration has not 201 * changed. 202 * 203 * @param enablePushMode start or stop push mode delivery 204 */ 205 public void enablePushModeDelivery(boolean enablePushMode) { 206 // does nothing for non-push protocols 207 } 208 209 /** 210 * Delete Store and its corresponding resources. 211 * @throws MessagingException 212 */ 213 public void delete() throws MessagingException { 214 } 215} 216