文件位置：
frameworks\base\services\jni
动态注册文件：onload.cpp
[cpp]
#include "JNIHelp.h"
#include "jni.h"
#include "utils/Log.h"
#include "utils/misc.h"
namespace android {
int register_android_server_AlarmManagerService（JNIEnv* env）；
int register_android_server_BatteryService（JNIEnv* env）；
int register_android_server_InputManager（JNIEnv* env）；
int register_android_server_LightsService（JNIEnv* env）；
int register_android_server_PowerManagerService（JNIEnv* env）；
int register_android_server_VibratorService（JNIEnv* env）；
int register_android_server_SystemServer（JNIEnv* env）；
int register_android_server_location_GpsLocationProvider（JNIEnv* env）；
};
using namespace android;
extern "C" jint JNI_OnLoad（JavaVM* vm, void* reserved）
{
JNIEnv* env = NULL;
jint result = -1;
if （vm->GetEnv（（void**） &env, JNI_VERSION_1_4） != JNI_OK） {
LOGE（"GetEnv failed!"）；
return result;
}
LOG_ASSERT（env, "Could not retrieve the env!"）；
register_android_server_PowerManagerService（env）；
register_android_server_InputManager（env）；
register_android_server_LightsService（env）；
register_android_server_AlarmManagerService（env）；
register_android_server_BatteryService（env）；
register_android_server_VibratorService（env）；
register_android_server_SystemServer（env）；
register_android_server_location_GpsLocationProvider（env）；
return JNI_VERSION_1_4;
}
注册文件主要做了两件事情：1在android空间声明注册函数2.在C空间注册jni中注册相关的服务
将注册文件编译进内核
[cpp]
LOCAL_SRC_FILES:= \
com_android_server_AlarmManagerService.cpp \
com_android_server_BatteryService.cpp \
com_android_server_InputManager.cpp \
com_android_server_LightsService.cpp \
com_android_server_PowerManagerService.cpp \
com_android_server_SystemServer.cpp \
com_android_server_UsbService.cpp \
com_android_server_VibratorService.cpp \
com_android_server_location_GpsLocationProvider.cpp \
onload.cpp
3.JNI实现（com_android_server_LightsService.cpp）
[cpp]
/*
* 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,
* 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.
*/
#define LOG_TAG "LightsService"
#include "jni.h"
#include "JNIHelp.h"
#include "android_runtime/AndroidRuntime.h"
#include <utils/misc.h>
#include <utils/Log.h>
#include <hardware/hardware.h>
#include <hardware/lights.h>
#include <stdio.h>
namespace android
{
// These values must correspond with the LIGHT_ID constants in
// LightsService.java
enum {
LIGHT_INDEX_BACKLIGHT = 0,
LIGHT_INDEX_KEYBOARD = 1,
LIGHT_INDEX_BUTTONS = 2,
LIGHT_INDEX_BATTERY = 3,
LIGHT_INDEX_NOTIFICATIONS = 4,
LIGHT_INDEX_ATTENTION = 5,
LIGHT_INDEX_BLUETOOTH = 6,
LIGHT_INDEX_WIFI = 7,
LIGHT_COUNT
};