Java tutorial
/******************************************************************************* * Mirakel is an Android App for managing your ToDo-Lists * * Copyright (c) 2013-2015 Anatolij Zelenin, Georg Semmler. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. ******************************************************************************/ package de.azapps.tools; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import com.google.common.base.Optional; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.text.SimpleDateFormat; import java.util.Date; import de.azapps.mirakel.helper.MirakelCommonPreferences; public class Log { private static final String TAG = "de.azapps.tools.Log"; @NonNull private static Optional<FileWriter> fileWriter = Optional.absent(); private static boolean writeToFile = false; public static void enableLoggingToFile() { writeToFile = true; } public static void disableLoggingToFile() { writeToFile = false; fileWriter = Optional.absent(); } public static int d(final @Nullable String tag, final @Nullable String msg) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("d", tag, msg); return android.util.Log.d(tag, msg); } return 0; } public static int d(final @Nullable String tag, final @Nullable String msg, final Throwable e) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("d", tag, msg, e); return android.util.Log.d(tag, msg, e); } return 0; } public static int e(final @Nullable String tag, final @Nullable String msg) { if ((tag == null) || (msg == null)) { return 0; } write("e", tag, msg); return android.util.Log.e(tag, msg); } public static int e(final @Nullable String tag, final @Nullable String msg, final Throwable tr) { if ((tag == null) || (msg == null)) { return 0; } write("e", tag, msg, tr); return android.util.Log.e(tag, msg, tr); } private static String getStackTraceString(final Throwable tr) { return android.util.Log.getStackTraceString(tr); } public static int i(final @Nullable String tag, final @Nullable String msg) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("i", tag, msg); return android.util.Log.i(tag, msg); } return 0; } public static int i(final @Nullable String tag, final @Nullable String msg, final Throwable e) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("i", tag, msg, e); return android.util.Log.i(tag, msg, e); } return 0; } public static int v(final @Nullable String tag, final @Nullable String msg) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("v", tag, msg); return android.util.Log.v(tag, msg); } return 0; } public static int v(final @Nullable String tag, final @Nullable String msg, final Throwable e) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("v", tag, msg, e); return android.util.Log.v(tag, msg, e); } return 0; } public static int w(final @Nullable String tag, final @Nullable String msg) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("w", tag, msg); return android.util.Log.w(tag, msg); } return 0; } public static int w(final @Nullable String tag, final @Nullable String msg, final Throwable e) { if ((tag == null) || (msg == null)) { return 0; } if (MirakelCommonPreferences.isDebug()) { write("w", tag, msg, e); return android.util.Log.w(tag, msg, e); } return 0; } public static int wtf(final @Nullable String tag, final @Nullable String msg) { if ((tag == null) || (msg == null)) { return 0; } write("wtf", tag, msg); return android.util.Log.wtf(tag, msg); } public static int wtf(final @Nullable String tag, final @Nullable String msg, final Throwable e) { if ((tag == null) || (msg == null)) { return 0; } write("wtf", tag, msg, e); return android.util.Log.wtf(tag, e); } private static String getTime() { return new SimpleDateFormat("dd-MM-yyyy_HH-mm-ss").format(new Date()); } private static void init() { if (fileWriter.isPresent()) { return; } try { fileWriter = Optional.of(new FileWriter(new File(FileUtils.getLogDir(), getTime() + ".log"))); } catch (final IOException e) { writeToFile = false; fileWriter = Optional.absent(); Log.e(TAG, "Could not open file for logging"); } } public static void destroy() { if (fileWriter.isPresent()) { try { fileWriter.get().close(); } catch (final IOException e) { android.util.Log.wtf(TAG, "failed to close log", e); } } } public static void write(final String critic, final String tag, final String msg) { write(critic, tag, msg, null); } public static void write(final String critic, final String tag, final String msg, final Throwable throwable) { if (!writeToFile) { return; } init(); if (fileWriter.isPresent()) { String stacktrace = ""; if (throwable != null) { stacktrace = "\nStackTrace:" + getStackTraceString(throwable); } try { fileWriter.get().write(getTime() + "::" + critic + "::" + tag + "::" + msg + stacktrace + '\n'); fileWriter.get().flush(); } catch (final IOException e) { fileWriter = Optional.absent(); writeToFile = false;// Prevent stackoverflow from recursive // calling Log.e(TAG, "Could not write to file for logging", e); } } } public static void longInfo(final @Nullable String str) { if (str == null) { return; } if (str.length() > 4000) { Log.i(TAG, str.substring(0, 4000)); longInfo(str.substring(4000)); } else { Log.i(TAG, str); } } }