binder对于boolean类型的传递

通过写了一个AIDL文件,查看自动生成的java文件代码得出的结论:

假如有:  boolean loadNativeSharedLib(String libPathName);

则对应的binder通信的实际操作为:

写入:

@Override public boolean loadNativeSharedLib(java.lang.String libPathName) throws android.os.RemoteException
{
android.os.Parcel _data = android.os.Parcel.obtain();
android.os.Parcel _reply = android.os.Parcel.obtain();
boolean _result;
try {
_data.writeInterfaceToken(DESCRIPTOR);
_data.writeString(libPathName);
mRemote.transact(Stub.TRANSACTION_loadNativeSharedLib, _data, _reply, 0);
_reply.readException();
_result = (0!=_reply.readInt());
}
finally {
_reply.recycle();
_data.recycle();
}
return _result;
}

处理&返回:

case TRANSACTION_loadNativeSharedLib:
{
data.enforceInterface(DESCRIPTOR);
java.lang.String _arg0;
_arg0 = data.readString();
boolean _result = this.loadNativeSharedLib(_arg0);
reply.writeNoException();
reply.writeInt(((_result)?(1):(0)));
return true;
}

需要重点关注:

将boolean转化为int: reply.writeInt(((_result)?(1):(0)));

将int 还原boolean: _result = (0!=_reply.readInt());

这是一种简洁有效地方式.

之所以分析这个,是因为: 1)在native code调用java的service时需要考虑传递序列. 2)不借助aidl工具生成时,也需要手动实现上述两个block的代码