aidl生成binder代码

一、背景

编写binder接口工作量大，google已提供aidl工具进行自动生成

二、aidl使用说明

找到aidl.exe可执行文件，在Android studio  设置中Android SDK找到 Android SDK Location存放路径build-tools/版本号/文件夹下（linux系统上为aidl）

windows上演示示例

//IStudent.aidl
interface IStudent {
    int getStudentId(String name);
}

工具生成后效果：

└─aidl
    │  IStudent.aidl
    │  IStudent.java
    │
    └─cpp
            BnStudent.h
            BpStudent.h
            IStudent.cpp
            IStudent.h

自动生成Java代码

aidl.exe --lang=java -IE:\project\demo\aidl E:\project\demo\aidl\IStudent.aidl -o E:\project\demo\aidl
#–lang={java|cpp|ndk}  指定生成接口类型。如果不指定，默认生成Java文件。
#-o 指定输出目录
#-I DIR, --include=DIR import搜索路径，指定依赖的aidl文件所在目录

//IStudent.java
/*
 * This file is auto-generated.  DO NOT MODIFY.
 * Using: aidl.exe --lang=java -IE:\\project\\demo\\aidl E:\\project\\demo\\aidl\\IStudent.aidl -o E:\\project\\demo\\aidl
 */
public interface IStudent extends android.os.IInterface
{
  /** Default implementation for IStudent. */
  public static class Default implements IStudent
  {
    @Override public int getStudentId(java.lang.String name) throws android.os.RemoteException
    {
      return 0;
    }
    @Override
    public android.os.IBinder asBinder() {
      return null;
    }
  }
  /** Local-side IPC implementation stub class. */
  public static abstract class Stub extends android.os.Binder implements IStudent
  {
    /** Construct the stub at attach it to the interface. */
    @SuppressWarnings("this-escape")
    public Stub()
    {
      this.attachInterface(this, DESCRIPTOR);
    }
    /**
     * Cast an IBinder object into an IStudent interface,
     * generating a proxy if needed.
     */
  public static IStudent asInterface(android.os.IBinder obj)
    {
      if ((obj==null)) {
        return null;
      }
      android.os.IInterface iin = obj.queryLocalInterface(DESCRIPTOR);
      if (((iin!=null)&&(iin instanceof IStudent))) {
        return ((IStudent)iin);
      }
      return new IStudent.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
    {
      java.lang.String descriptor = DESCRIPTOR;
      if (code >= android.os.IBinder.FIRST_CALL_TRANSACTION && code <= android.os.IBinder.LAST_CALL_TRANSACTION) {
        data.enforceInterface(descriptor);
      }
      if (code == INTERFACE_TRANSACTION) {
        reply.writeString(descriptor);
        return true;
      }
      switch (code)
      {
        case TRANSACTION_getStudentId:
        {
          java.lang.String _arg0;
          _arg0 = data.readString();
          int _result = this.getStudentId(_arg0);
          reply.writeNoException();
          reply.writeInt(_result);
          break;
        }
        default:
        {
          return super.onTransact(code, data, reply, flags);
        }
      }
      return true;
    }
    private static class Proxy implements IStudent
    {
      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 int getStudentId(java.lang.String name) 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);
          _data.writeString(name);
          boolean _status = mRemote.transact(Stub.TRANSACTION_getStudentId, _data, _reply, 0);
          _reply.readException();
          _result = _reply.readInt();
        }
        finally {
          _reply.recycle();
          _data.recycle();
        }
        return _result;
      }
    }
    static final int TRANSACTION_getStudentId = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);
  }
  /** @hide */
  public static final java.lang.String DESCRIPTOR = "IStudent";
  public int getStudentId(java.lang.String name) throws android.os.RemoteException;
}

自动生成C++代码

aidl.exe --lang=cpp -IE:\project\demo\aidl E:\project\demo\aidl\IStudent.aidl -h E:\project\demo\aidl\cpp -o E:\project\demo\aidl\cpp

//BnStudent.h
/*
 * This file is auto-generated.  DO NOT MODIFY.
 * Using: aidl.exe --lang=cpp -IE:\\project\\demo\\aidl E:\\project\\demo\\aidl\\IStudent.aidl -h E:\\project\\demo\\aidl\\cpp -o E:\\project\\demo\\aidl\\cpp
 */
#pragma once

#include <binder/IInterface.h>
#include <IStudent.h>
#include <BnStudent.h>
#include <binder/Delegate.h>


class BnStudent : public ::android::BnInterface<IStudent> {
public:
  static constexpr uint32_t TRANSACTION_getStudentId = ::android::IBinder::FIRST_CALL_TRANSACTION + 0;
  explicit BnStudent();
  ::android::status_t onTransact(uint32_t _aidl_code, const ::android::Parcel& _aidl_data, ::android::Parcel* _aidl_reply, uint32_t _aidl_flags) override;
};  // class BnStudent

class IStudentDelegator : public BnStudent {
public:
  explicit IStudentDelegator(const ::android::sp<IStudent> &impl) : _aidl_delegate(impl) {}

  ::android::sp<IStudent> getImpl() { return _aidl_delegate; }
  ::android::binder::Status getStudentId(const ::android::String16& name, int32_t* _aidl_return) override {
    return _aidl_delegate->getStudentId(name, _aidl_return);
  }
private:
  ::android::sp<IStudent> _aidl_delegate;
};  // class IStudentDelegator

//BpStudent.h
/*
 * This file is auto-generated.  DO NOT MODIFY.
 * Using: aidl.exe --lang=cpp -IE:\\project\\demo\\aidl E:\\project\\demo\\aidl\\IStudent.aidl -h E:\\project\\demo\\aidl\\cpp -o E:\\project\\demo\\aidl\\cpp
 */
#pragma once

#include <binder/IBinder.h>
#include <binder/IInterface.h>
#include <utils/Errors.h>
#include <IStudent.h>

class BpStudent : public ::android::BpInterface<IStudent> {
public:
  explicit BpStudent(const ::android::sp<::android::IBinder>& _aidl_impl);
  virtual ~BpStudent() = default;
  ::android::binder::Status getStudentId(const ::android::String16& name, int32_t* _aidl_return) override;
};  // class BpStudent

//IStudent.cpp
/*
 * This file is auto-generated.  DO NOT MODIFY.
 * Using: aidl.exe --lang=cpp -IE:\\project\\demo\\aidl E:\\project\\demo\\aidl\\IStudent.aidl -h E:\\project\\demo\\aidl\\cpp -o E:\\project\\demo\\aidl\\cpp
 */
#include <IStudent.h>
#include <BpStudent.h>
DO_NOT_DIRECTLY_USE_ME_IMPLEMENT_META_INTERFACE(Student, "IStudent")
#include <BpStudent.h>
#include <BnStudent.h>
#include <binder/Parcel.h>


BpStudent::BpStudent(const ::android::sp<::android::IBinder>& _aidl_impl)
    : BpInterface<IStudent>(_aidl_impl){
}

::android::binder::Status BpStudent::getStudentId(const ::android::String16& name, int32_t* _aidl_return) {
  ::android::Parcel _aidl_data;
  _aidl_data.markForBinder(remoteStrong());
  ::android::Parcel _aidl_reply;
  ::android::status_t _aidl_ret_status = ::android::OK;
  ::android::binder::Status _aidl_status;
  _aidl_ret_status = _aidl_data.writeInterfaceToken(getInterfaceDescriptor());
  if (((_aidl_ret_status) != (::android::OK))) {
    goto _aidl_error;
  }
  _aidl_ret_status = _aidl_data.writeString16(name);
  if (((_aidl_ret_status) != (::android::OK))) {
    goto _aidl_error;
  }
  _aidl_ret_status = remote()->transact(BnStudent::TRANSACTION_getStudentId, _aidl_data, &_aidl_reply, 0);
  if (_aidl_ret_status == ::android::UNKNOWN_TRANSACTION && IStudent::getDefaultImpl()) [[unlikely]] {
     return IStudent::getDefaultImpl()->getStudentId(name, _aidl_return);
  }
  if (((_aidl_ret_status) != (::android::OK))) {
    goto _aidl_error;
  }
  _aidl_ret_status = _aidl_status.readFromParcel(_aidl_reply);
  if (((_aidl_ret_status) != (::android::OK))) {
    goto _aidl_error;
  }
  if (!_aidl_status.isOk()) {
    return _aidl_status;
  }
  _aidl_ret_status = _aidl_reply.readInt32(_aidl_return);
  if (((_aidl_ret_status) != (::android::OK))) {
    goto _aidl_error;
  }
  _aidl_error:
  _aidl_status.setFromStatusT(_aidl_ret_status);
  return _aidl_status;
}

#include <BnStudent.h>
#include <binder/Parcel.h>
#include <binder/Stability.h>


BnStudent::BnStudent()
{
  ::android::internal::Stability::markCompilationUnit(this);
}

::android::status_t BnStudent::onTransact(uint32_t _aidl_code, const ::android::Parcel& _aidl_data, ::android::Parcel* _aidl_reply, uint32_t _aidl_flags) {
  ::android::status_t _aidl_ret_status = ::android::OK;
  switch (_aidl_code) {
  case BnStudent::TRANSACTION_getStudentId:
  {
    ::android::String16 in_name;
    int32_t _aidl_return;
    if (!(_aidl_data.checkInterface(this))) {
      _aidl_ret_status = ::android::BAD_TYPE;
      break;
    }
    _aidl_ret_status = _aidl_data.readString16(&in_name);
    if (((_aidl_ret_status) != (::android::OK))) {
      break;
    }
    ::android::binder::Status _aidl_status(getStudentId(in_name, &_aidl_return));
    _aidl_ret_status = _aidl_status.writeToParcel(_aidl_reply);
    if (((_aidl_ret_status) != (::android::OK))) {
      break;
    }
    if (!_aidl_status.isOk()) {
      break;
    }
    _aidl_ret_status = _aidl_reply->writeInt32(_aidl_return);
    if (((_aidl_ret_status) != (::android::OK))) {
      break;
    }
  }
  break;
  default:
  {
    _aidl_ret_status = ::android::BBinder::onTransact(_aidl_code, _aidl_data, _aidl_reply, _aidl_flags);
  }
  break;
  }
  if (_aidl_ret_status == ::android::UNEXPECTED_NULL) {
    _aidl_ret_status = ::android::binder::Status::fromExceptionCode(::android::binder::Status::EX_NULL_POINTER).writeOverParcel(_aidl_reply);
  }
  return _aidl_ret_status;
}