services/device/time_zone_monitor/android/java/src/org/chromium/device/time_zone_monitor/TimeZoneMonitor.java

// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package org.chromium.device.time_zone_monitor;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;

import org.chromium.base.ContextUtils;
import org.chromium.base.Log;
import org.chromium.base.annotations.CalledByNative;
import org.chromium.base.annotations.JNINamespace;
import org.chromium.base.annotations.NativeMethods;

/**
 * Android implementation details for device::TimeZoneMonitorAndroid.
 */
@JNINamespace("device")
class TimeZoneMonitor {
    private static final String TAG = "TimeZoneMonitor";

    private final IntentFilter mFilter = new IntentFilter(Intent.ACTION_TIMEZONE_CHANGED);
    private final BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if (!intent.getAction().equals(Intent.ACTION_TIMEZONE_CHANGED)) {
                Log.e(TAG, "unexpected intent");
                return;
            }

            TimeZoneMonitorJni.get().timeZoneChangedFromJava(mNativePtr, TimeZoneMonitor.this);
        }
    };

    private long mNativePtr;

    /**
     * Start listening for intents.
     * @param nativePtr The native device::TimeZoneMonitorAndroid to notify of time zone changes.
     */
    private TimeZoneMonitor(long nativePtr) {
        mNativePtr = nativePtr;
        ContextUtils.getApplicationContext().registerReceiver(mBroadcastReceiver, mFilter);
    }

    @CalledByNative
    static TimeZoneMonitor getInstance(long nativePtr) {
        return new TimeZoneMonitor(nativePtr);
    }

    /**
     * Stop listening for intents.
     */
    @CalledByNative
    void stop() {
        ContextUtils.getApplicationContext().unregisterReceiver(mBroadcastReceiver);
        mNativePtr = 0;
    }

    @NativeMethods
    interface Natives {
        /**
         * Native JNI call to device::TimeZoneMonitorAndroid::TimeZoneChanged. See
         * device/time_zone_monitor/time_zone_monitor_android.cc.
         */
        void timeZoneChangedFromJava(long nativeTimeZoneMonitorAndroid, TimeZoneMonitor caller);
    }
}