Java tutorial
/* * Copyright (C) 2007 The Android Open Source Project * * 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.android.sdkstats; import com.android.prefs.AndroidLocation; import com.android.prefs.AndroidLocation.AndroidLocationException; import org.eclipse.jface.preference.PreferenceStore; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.util.Random; /** * Manages persistence settings for DDMS. * * For convenience, this also stores persistence settings related to the "server stats" ping * as well as some ADT settings that are SDK specific but not workspace specific. */ public class DdmsPreferenceStore { public final static String PING_OPT_IN = "pingOptIn"; //$NON-NLS-1$ private final static String PING_TIME = "pingTime"; //$NON-NLS-1$ private final static String PING_ID = "pingId"; //$NON-NLS-1$ private final static String ADT_USED = "adtUsed"; //$NON-NLS-1$ private final static String LAST_SDK_PATH = "lastSdkPath"; //$NON-NLS-1$ /** * PreferenceStore for DDMS. * Creation and usage must be synchronized on {@code DdmsPreferenceStore.class}. * Don't use it directly, instead retrieve it via {@link #getPreferenceStore()}. */ private static volatile PreferenceStore sPrefStore; public DdmsPreferenceStore() { } /** * Returns the DDMS {@link PreferenceStore}. * This keeps a static reference on the store, so consequent calls will * return always the same store. */ public PreferenceStore getPreferenceStore() { synchronized (DdmsPreferenceStore.class) { if (sPrefStore == null) { // get the location of the preferences String homeDir = null; try { homeDir = AndroidLocation.getFolder(); } catch (AndroidLocationException e1) { // pass, we'll do a dummy store since homeDir is null } if (homeDir == null) { sPrefStore = new PreferenceStore(); return sPrefStore; } assert homeDir != null; String rcFileName = homeDir + "ddms.cfg"; //$NON-NLS-1$ // also look for an old pref file in the previous location String oldPrefPath = System.getProperty("user.home") //$NON-NLS-1$ + File.separator + ".ddmsrc"; //$NON-NLS-1$ File oldPrefFile = new File(oldPrefPath); if (oldPrefFile.isFile()) { FileOutputStream fileOutputStream = null; try { PreferenceStore oldStore = new PreferenceStore(oldPrefPath); oldStore.load(); fileOutputStream = new FileOutputStream(rcFileName); oldStore.save(fileOutputStream, ""); //$NON-NLS-1$ oldPrefFile.delete(); PreferenceStore newStore = new PreferenceStore(rcFileName); newStore.load(); sPrefStore = newStore; } catch (IOException e) { // create a new empty store. sPrefStore = new PreferenceStore(rcFileName); } finally { if (fileOutputStream != null) { try { fileOutputStream.close(); } catch (IOException e) { // pass } } } } else { sPrefStore = new PreferenceStore(rcFileName); try { sPrefStore.load(); } catch (IOException e) { System.err.println("Error Loading DDMS Preferences"); } } } assert sPrefStore != null; return sPrefStore; } } /** * Save the prefs to the config file. */ public void save() { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { try { prefs.save(); } catch (IOException ioe) { // FIXME com.android.dmmlib.Log.w("ddms", "Failed saving prefs file: " + ioe.getMessage()); } } } // ---- Utility methods to access some specific prefs ---- /** * Indicates whether the ping ID is set. * This should be true when {@link #isPingOptIn()} is true. * * @return true if a ping ID is set, which means the user gave permission * to use the ping service. */ public boolean hasPingId() { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { return prefs != null && prefs.contains(PING_ID); } } /** * Retrieves the current ping ID, if set. * To know if the ping ID is set, use {@link #hasPingId()}. * <p/> * There is no magic value reserved for "missing ping id or invalid store". * The only proper way to know if the ping id is missing is to use {@link #hasPingId()}. */ public long getPingId() { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { // Note: getLong() returns 0L if the ID is missing so we do that too when // there's no store. return prefs == null ? 0L : prefs.getLong(PING_ID); } } /** * Generates a new random ping ID and saves it in the preference store. * * @return The new ping ID. */ public long generateNewPingId() { PreferenceStore prefs = getPreferenceStore(); Random rnd = new Random(); long id = rnd.nextLong(); synchronized (DdmsPreferenceStore.class) { prefs.setValue(PING_ID, id); try { prefs.save(); } catch (IOException e) { /* ignore exceptions while saving preferences */ } } return id; } /** * Returns the "ping opt in" value from the preference store. * This would be true if there's a valid preference store and * the user opted for sending ping statistics. */ public boolean isPingOptIn() { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { return prefs != null && prefs.contains(PING_OPT_IN); } } /** * Saves the "ping opt in" value in the preference store. * * @param optIn The new user opt-in value. */ public void setPingOptIn(boolean optIn) { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { prefs.setValue(PING_OPT_IN, optIn); try { prefs.save(); } catch (IOException e) { /* ignore exceptions while saving preferences */ } } } /** * Retrieves the ping time for the given app from the preference store. * Callers should use {@link System#currentTimeMillis()} for time stamps. * * @param app The app name identifier. * @return 0L if we don't have a preference store or there was no time * recorded in the store for the requested app. Otherwise the time stamp * from the store. */ public long getPingTime(String app) { PreferenceStore prefs = getPreferenceStore(); String timePref = PING_TIME + "." + app; //$NON-NLS-1$ synchronized (DdmsPreferenceStore.class) { return prefs == null ? 0 : prefs.getLong(timePref); } } /** * Sets the ping time for the given app from the preference store. * Callers should use {@link System#currentTimeMillis()} for time stamps. * * @param app The app name identifier. * @param timeStamp The time stamp from the store. * 0L is a special value that should not be used. */ public void setPingTime(String app, long timeStamp) { PreferenceStore prefs = getPreferenceStore(); String timePref = PING_TIME + "." + app; //$NON-NLS-1$ synchronized (DdmsPreferenceStore.class) { prefs.setValue(timePref, timeStamp); try { prefs.save(); } catch (IOException ioe) { /* ignore exceptions while saving preferences */ } } } /** * True if this is the first time the users runs ADT, which is detected by * the lack of the setting set using {@link #setAdtUsed(boolean)} * or this value being set to true. * * @return true if ADT has been used before * * @see #setAdtUsed(boolean) */ public boolean isAdtUsed() { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { if (prefs == null || !prefs.contains(ADT_USED)) { return false; } return prefs.getBoolean(ADT_USED); } } /** * Sets whether the ADT startup wizard has been shown. * ADT sets first to false once the welcome wizard has been shown once. * * @param used true if ADT has been used */ public void setAdtUsed(boolean used) { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { prefs.setValue(ADT_USED, used); try { prefs.save(); } catch (IOException ioe) { /* ignore exceptions while saving preferences */ } } } /** * Retrieves the last SDK OS path. * <p/> * This is just an information value, the path may not exist, may not * even be on an existing file system and/or may not point to an SDK * anymore. * * @return The last SDK OS path from the preference store, or null if * there is no store or an empty string if it is not defined. */ public String getLastSdkPath() { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { return prefs == null ? null : prefs.getString(LAST_SDK_PATH); } } /** * Sets the last SDK OS path. * * @param osSdkPath The SDK OS Path. Can be null or empty. */ public void setLastSdkPath(String osSdkPath) { PreferenceStore prefs = getPreferenceStore(); synchronized (DdmsPreferenceStore.class) { prefs.setValue(LAST_SDK_PATH, osSdkPath); try { prefs.save(); } catch (IOException ioe) { /* ignore exceptions while saving preferences */ } } } }