标签：des android style class blog code
一、
1、定义硬件访问服务接口(为了进程间通信)
~/android-2.3_r1/frameworks/base
----Android.mk
----/core/java/android/os/IFregService.aidl
Android系统提供了一种描述语言来定义具有跨进程访问能力的服务接口，这种描述语言称为Android接口描述语言(AIDL)。
IFregService.aidl
package android.os;
interface IFregService {
void setVal(int val);
int getVal();
}
Android.mk
LOCAL_SRC_FILES += / .................................................................... core/java/android/os/IVibratorService.aidl / core/java/android/os/IFregService.aidl / core/java/android/service/urlrenderer/IUrlRendererService.aidl /
编译aidl：
生成的IFregService.java文件位于out/target/common/obj/JAVA_LIBRARIES/framework_intermediates/src/core/java/android/os中。
IFregService.java
/*
* This file is auto-generated. DO NOT MODIFY.
* Original file: frameworks/base/core/java/android/os/IFregService.aidl
*/
package android.os;
public interface IFregService extends android.os.IInterface {
/** Local-side IPC implementation stub class. */
public static abstract class Stub extends android.os.Binder implements
android.os.IFregService {
private static final java.lang.String DESCRIPTOR = "android.os.IFregService";
/** Construct the stub at attach it to the interface. */
public Stub() {
this.attachInterface(this, DESCRIPTOR);
}
/**
* Cast an IBinder object into an android.os.IFregService interface,
* generating a proxy if needed.
*/
public static android.os.IFregService asInterface(android.os.IBinder obj) {
if ((obj == null)) {
return null;
}
android.os.IInterface iin = (android.os.IInterface) obj
.queryLocalInterface(DESCRIPTOR);
if (((iin != null) && (iin instanceof android.os.IFregService))) {
return ((android.os.IFregService) iin);
}
return new android.os.IFregService.Stub.Proxy(obj);
}
public android.os.IBinder asBinder() {
return this;
}
@Override
public boolean onTransact(int code, android.os.Parcel data,
android.os.Parcel reply, int flags)
throws android.os.RemoteException {
switch (code) {
case INTERFACE_TRANSACTION: {
reply.writeString(DESCRIPTOR);
return true;
}
case TRANSACTION_setVal: {
data.enforceInterface(DESCRIPTOR);
int _arg0;
_arg0 = data.readInt();
this.setVal(_arg0);
reply.writeNoException();
return true;
}
case TRANSACTION_getVal: {
data.enforceInterface(DESCRIPTOR);
int _result = this.getVal();
reply.writeNoException();
reply.writeInt(_result);
return true;
}
}
return super.onTransact(code, data, reply, flags);
}
private static class Proxy implements android.os.IFregService {
private android.os.IBinder mRemote;
Proxy(android.os.IBinder remote) {
mRemote = remote;
}
public android.os.IBinder asBinder() {
return mRemote;
}
public java.lang.String getInterfaceDescriptor() {
return DESCRIPTOR;
}
public void setVal(int val) throws android.os.RemoteException {
android.os.Parcel _data = android.os.Parcel.obtain();
android.os.Parcel _reply = android.os.Parcel.obtain();
try {
_data.writeInterfaceToken(DESCRIPTOR);
_data.writeInt(val);
mRemote.transact(Stub.TRANSACTION_setVal, _data, _reply, 0);
_reply.readException();
} finally {
_reply.recycle();
_data.recycle();
}
}
public int getVal() throws android.os.RemoteException {
android.os.Parcel _data = android.os.Parcel.obtain();
android.os.Parcel _reply = android.os.Parcel.obtain();
int _result;
try {
_data.writeInterfaceToken(DESCRIPTOR);
mRemote.transact(Stub.TRANSACTION_getVal, _data, _reply, 0);
_reply.readException();
_result = _reply.readInt();
} finally {
_reply.recycle();
_data.recycle();
}
return _result;
}
}
static final int TRANSACTION_setVal = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);
static final int TRANSACTION_getVal = (android.os.IBinder.FIRST_CALL_TRANSACTION + 1);
}
public void setVal(int val) throws android.os.RemoteException;
public int getVal() throws android.os.RemoteException;
}
最后生成的framework.jar文件位于out/target/product/generic/system/framework中。
3、实现硬件访问服务
~/android-2.3_r1/frameworks/base/services/java/com/android/server
----FregService.java
package com.android.server;
import android.content.Context;
import android.os.IFregService;
import android.util.Slog;
public class FregService extends IFregService.Stub {
private static final String TAG = "FregService";
private int mPtr = 0;
FregService() {
mPtr = init_native();
if(mPtr == 0) {
Slog.e(TAG, "Failed to initialize freg service.");
}
}
public void setVal(int val) {
if(mPtr == 0) {
Slog.e(TAG, "Freg service is not initialized.");
return;
}
setVal_native(mPtr, val);
}
public int getVal() {
if(mPtr == 0) {
Slog.e(TAG, "Freg service is not initialized.");
return 0;
}
return getVal_native(mPtr);
}
private static native int init_native();//调用jni方法
private static native void setVal_native(int ptr, int val);
private static native int getVal_native(int ptr);
};
编译生成的services.jar位于out/target/product/generic/system/framework中。
二、
1、启动硬件访问服务
~/android-2.3_r1/frameworks/base/services/java/com/android/server
----SystemServer.java
修改ServerThread类的成员函数run的实现，如下所示：
@Override
public void run() {
....................................................................................
try {
Slog.i(TAG, "DiskStats Service");
ServiceManager.addService("diskstats", new DiskStatsService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting DiskStats Service", e);
}
try {
Slog.i(TAG, "Hello Service");
ServiceManager.addService("hello", new FregService());
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Freg Service", e);
}
编译生成的services.jar位于out/target/product/generic/system/framework中。
最后把services.jar和framework.jar重新打包进入system.img，位于out/target/product/gerneric中。
标签：des android style class blog code
原文地址：http://blog.csdn.net/jltxgcy/article/details/29372453
