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Android example source code file (BootReceiver.java)

This example Android source code file (BootReceiver.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" TM.

Java - Android tags/keywords

android, bootreceiver, can't, content, dropboxmanager, exception, file, intent, io, ioexception, log_size, network, old_updater_class, old_updater_package, os, override, provider, sharedpreferences, string, system_recovery_log

The BootReceiver.java Android example source code

 * Copyright (C) 2009 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,
 * See the License for the specific language governing permissions and
 * limitations under the License.

package com.android.server;

import android.content.BroadcastReceiver;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.net.Downloads;
import android.os.Build;
import android.os.DropBoxManager;
import android.os.FileObserver;
import android.os.FileUtils;
import android.os.RecoverySystem;
import android.os.SystemProperties;
import android.provider.Settings;
import android.util.Slog;

import java.io.File;
import java.io.IOException;

 * Performs a number of miscellaneous, non-system-critical actions
 * after the system has finished booting.
public class BootReceiver extends BroadcastReceiver {
    private static final String TAG = "BootReceiver";

    // Maximum size of a logged event (files get truncated if they're longer)
    private static final int LOG_SIZE = 65536;

    private static final File TOMBSTONE_DIR = new File("/data/tombstones");

    // The pre-froyo package and class of the system updater, which
    // ran in the system process.  We need to remove its packages here
    // in order to clean up after a pre-froyo-to-froyo update.
    private static final String OLD_UPDATER_PACKAGE =
    private static final String OLD_UPDATER_CLASS =

    // Keep a reference to the observer so the finalizer doesn't disable it.
    private static FileObserver sTombstoneObserver = null;

    public void onReceive(final Context context, Intent intent) {
        try {
            // Start the load average overlay, if activated
            ContentResolver res = context.getContentResolver();
            if (Settings.System.getInt(res, Settings.System.SHOW_PROCESSES, 0) != 0) {
                Intent loadavg = new Intent(context, com.android.server.LoadAverageService.class);
        } catch (Exception e) {
            Slog.e(TAG, "Can't start load average service", e);

        // Log boot events in the background to avoid blocking the main thread with I/O
        new Thread() {
            public void run() {
                try {
                } catch (Exception e) {
                    Slog.e(TAG, "Can't log boot events", e);
                try {
                } catch (Exception e) {
                    Slog.e(TAG, "Can't remove old update packages", e);


    private void removeOldUpdatePackages(Context ctx) {

    private void logBootEvents(Context ctx) throws IOException {
        final DropBoxManager db = (DropBoxManager) ctx.getSystemService(Context.DROPBOX_SERVICE);
        final SharedPreferences prefs = ctx.getSharedPreferences("log_files", Context.MODE_PRIVATE);
        final String headers = new StringBuilder(512)
            .append("Build: ").append(Build.FINGERPRINT).append("\n")
            .append("Hardware: ").append(Build.BOARD).append("\n")
            .append("Bootloader: ").append(Build.BOOTLOADER).append("\n")
            .append("Radio: ").append(Build.RADIO).append("\n")
            .append("Kernel: ")
            .append(FileUtils.readTextFile(new File("/proc/version"), 1024, "...\n"))

        String recovery = RecoverySystem.handleAftermath();
        if (recovery != null && db != null) {
            db.addText("SYSTEM_RECOVERY_LOG", headers + recovery);

        if (SystemProperties.getLong("ro.runtime.firstboot", 0) == 0) {
            String now = Long.toString(System.currentTimeMillis());
            SystemProperties.set("ro.runtime.firstboot", now);
            if (db != null) db.addText("SYSTEM_BOOT", headers);

            // Negative sizes mean to take the *tail* of the file (see FileUtils.readTextFile())
            addFileToDropBox(db, prefs, headers, "/proc/last_kmsg",
                    -LOG_SIZE, "SYSTEM_LAST_KMSG");
            addFileToDropBox(db, prefs, headers, "/cache/recovery/log",
                    -LOG_SIZE, "SYSTEM_RECOVERY_LOG");
            addFileToDropBox(db, prefs, headers, "/data/dontpanic/apanic_console",
                    -LOG_SIZE, "APANIC_CONSOLE");
            addFileToDropBox(db, prefs, headers, "/data/dontpanic/apanic_threads",
                    -LOG_SIZE, "APANIC_THREADS");
        } else {
            if (db != null) db.addText("SYSTEM_RESTART", headers);

        // Scan existing tombstones (in case any new ones appeared)
        File[] tombstoneFiles = TOMBSTONE_DIR.listFiles();
        for (int i = 0; tombstoneFiles != null && i < tombstoneFiles.length; i++) {
            addFileToDropBox(db, prefs, headers, tombstoneFiles[i].getPath(),
                    LOG_SIZE, "SYSTEM_TOMBSTONE");

        // Start watching for new tombstone files; will record them as they occur.
        // This gets registered with the singleton file observer thread.
        sTombstoneObserver = new FileObserver(TOMBSTONE_DIR.getPath(), FileObserver.CLOSE_WRITE) {
            public void onEvent(int event, String path) {
                try {
                    String filename = new File(TOMBSTONE_DIR, path).getPath();
                    addFileToDropBox(db, prefs, headers, filename, LOG_SIZE, "SYSTEM_TOMBSTONE");
                } catch (IOException e) {
                    Slog.e(TAG, "Can't log tombstone", e);


    private static void addFileToDropBox(
            DropBoxManager db, SharedPreferences prefs,
            String headers, String filename, int maxSize, String tag) throws IOException {
        if (db == null || !db.isTagEnabled(tag)) return;  // Logging disabled

        File file = new File(filename);
        long fileTime = file.lastModified();
        if (fileTime <= 0) return;  // File does not exist

        if (prefs != null) {
            long lastTime = prefs.getLong(filename, 0);
            if (lastTime == fileTime) return;  // Already logged this particular file
            prefs.edit().putLong(filename, fileTime).commit();

        Slog.i(TAG, "Copying " + filename + " to DropBox (" + tag + ")");
        db.addText(tag, headers + FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n"));

Other Android examples (source code examples)

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