Binder Class relation ship

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public interface ICat extends android.os.IInterface{    public java.lang.String getColor() throws android.os.RemoteException;    public double getWeight() throws android.os.RemoteException;/* 对于服务端不需要上述接口，调用通过消息解调得到 */    /** Local-side IPC implementation stub class. */======================================================================  stubStub提供了服务端的数据包解析，他需要本地的服务提供实际的数据。用户必须重载提供数据。    public static abstract class Stub extends android.os.Binder implements org.crazyit.service.ICat    {        private static final java.lang.String DESCRIPTOR = "org.crazyit.service.ICat";        /** Construct the stub at attach it to the interface. */        public Stub()        {            this.attachInterface(this, DESCRIPTOR);        }        /**         * Cast an IBinder object into an org.crazyit.service.ICat interface,         * generating a proxy if needed.         */        public static org.crazyit.service.ICat asInterface(android.os.IBinder obj)        {            if ((obj==null)) {                return null;            }            android.os.IInterface iin = obj.queryLocalInterface(DESCRIPTOR);            if (((iin!=null)&&(iin instanceof org.crazyit.service.ICat))) {                return ((org.crazyit.service.ICat)iin);            }            return new org.crazyit.service.ICat.Stub.Proxy(obj);        }        @Override 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_getColor:                {                    data.enforceInterface(DESCRIPTOR);                    java.lang.String _result = this.getColor();                    reply.writeNoException();                    reply.writeString(_result);                    return true;                }                case TRANSACTION_getWeight:                {                    data.enforceInterface(DESCRIPTOR);                    double _result = this.getWeight();                    reply.writeNoException();                    reply.writeDouble(_result);                    return true;                }            }            return super.onTransact(code, data, reply, flags);        }        ××××××××××××××××××××××××××××××××××××××××××××××××××××××××  Proxy        运行在client空间，在client使用asInterface函数和远端IBinder构造        private static class Proxy implements org.crazyit.service.ICat        {            private android.os.IBinder mRemote;            Proxy(android.os.IBinder remote)            {                mRemote = remote;            }            @Override public android.os.IBinder asBinder()            {                return mRemote;            }            public java.lang.String getInterfaceDescriptor()            {                return DESCRIPTOR;            }            @Override public java.lang.String getColor() throws android.os.RemoteException            {                android.os.Parcel _data = android.os.Parcel.obtain();                android.os.Parcel _reply = android.os.Parcel.obtain();                java.lang.String _result;                try {                    _data.writeInterfaceToken(DESCRIPTOR);                    mRemote.transact(Stub.TRANSACTION_getColor, _data, _reply, 0);                    _reply.readException();                    _result = _reply.readString();                }                finally {                    _reply.recycle();                    _data.recycle();                }                return _result;            }            @Override public double getWeight() throws android.os.RemoteException            {                android.os.Parcel _data = android.os.Parcel.obtain();                android.os.Parcel _reply = android.os.Parcel.obtain();                double _result;                try {                    _data.writeInterfaceToken(DESCRIPTOR);                    mRemote.transact(Stub.TRANSACTION_getWeight, _data, _reply, 0);                    _reply.readException();                    _result = _reply.readDouble();                }                finally {                    _reply.recycle();                    _data.recycle();                }                return _result;            }        }        ××××××××××××××××××××××××××××××××××××××××××××××××    Proxy        static final int TRANSACTION_getColor = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);        static final int TRANSACTION_getWeight = (android.os.IBinder.FIRST_CALL_TRANSACTION + 1);    }}public class Binder implements IBinder {    private IInterface mOwner;  /× 存储了实际的接口对象，可以为自己 ×/    private String mDescriptor;}public interface IInterface{    public IBinder asBinder();}
关于Messenger的接口。
IMessenge.Proxy -> IMessenger -> IInterface (client side interface object)
IMessenge.Stub -> IMessenger -> IInterface (server side interface object)
IMessenge.Stub -> Binder -> IBinder
IMessenge.Proxy wrap pointer to IMessenge.Stub，the pointer maybe Binder
BinderProxy -> IBinder 可能是客户在本端的IBinder对象。
Handler <<– >> MessengerImpl -> IMessenger.Stub
Messenger ->> MessengerImpl –>> Handler
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