Thrift0.8当接口返回类型i16/i32/i64/bool时，客户端无法捕获服务端抛出的异常

测试代码：

namespace java com.meituan.service

exception BugTestException{
    1: required i32 code;
    2: required string msg;
}

service HelloService {
    i32 bugCall() throws (1: BugTestException e);
}

实现类

@Service
public class HelloServiceImpl implements HelloService.Iface {
    @Override
    public int bugCall() throws BugTestException, TException {
        throw new BugTestException(100, "收不到就是bug");
    }
}

org.apache.thrift.ProcessFunction

当 getResult 执行出现异常

public static class bugCall_result implements org.apache.thrift.TBase<bugCall_result, bugCall_result._Fields>, java.io.Serializable, Cloneable {
    public int success; // required         
    public BugTestException e; // required  
}


@Override                                                                                            
protected bugCall_result getResult(I iface, bugCall_args args) throws org.apache.thrift.TException { 
    bugCall_result result = new bugCall_result();                                                    
    try {                                                                                            
        result.success = iface.bugCall();                                                            
        result.setSuccessIsSet(true);                                                                
    } catch (BugTestException e) {                                                                   
        result.e = e;                                                                                
    }                                                                                                
    return result;                                                                                   
}                                                                                                    

服务端也是返回 TMessageType.REPLY
result.write(oprot) --com.meituan.service.HelloService.bugCall_result.bugCall_resultStandardScheme#write

此时 struct.success 等于默认的 0，（Class 中基本类型默认值为 0，引用类型默认值为 null）

struct.isSetSuccess() 为 false。

客户端读取操作：

com.meituan.service.HelloService.Client#recv_bugCall

org.apache.thrift.TServiceClient#receiveBase

此时读取到的 msg.type == 2，即 TMessageType.REPLY。
com.meituan.service.HelloService.bugCall_result.bugCall_resultStandardScheme#read

struct.success 读取到默认值 0，thrift 认为读取到了正确的值，所以执行 setSuccessIsSet。

故 com.meituan.service.HelloService.Client#recv_bugCall 直接返回了默认的 0，而没有抛出异常。

解决 1

 public int recv_bugCall() throws BugTestException, org.apache.thrift.TException {
            bugCall_result result = new bugCall_result();
            receiveBase(result, "bugCall");
            // 先执行异常检查
          	if (result.e != null) {
                throw result.e;
            }
          	if (result.isSetSuccess()) {
                return result.success;
            }
            throw new org.apache.thrift.TApplicationException(org.apache.thrift.TApplicationException.MISSING_RESULT, "bugCall failed: unknown result");
        }

解决 2

将 getResult 用 try-catch 包装起来。
这也是 thrift 0.9 版本的解决方案。

try {                                                                                       
  result = getResult(iface, args);                                                          
} catch(TException tex) {                                                                   
  LOGGER.error("Internal error processing " + getMethodName(), tex);                        
  TApplicationException x = new TApplicationException(TApplicationException.INTERNAL_ERROR, 
    "Internal error processing " + getMethodName());                                        
  oprot.writeMessageBegin(new TMessage(getMethodName(), TMessageType.EXCEPTION, seqid));    
  x.write(oprot);                                                                           
  oprot.writeMessageEnd();                                                                  
  oprot.getTransport().flush();                                                             
  return;                                                                                   
}