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怎么在Java IDL中传递null参数

发布时间: 2011-12-12 22:59:56 作者: rapoo

如何在Java IDL中传递null参数?
1.I need to transfer a complex type with an array variable member in a
Java-IDL based program. But if the array is empty, the program will
report a java.lang.NullPointerException.
Is there any solution to it except block the request in client side?

The following is my idl:

#ifndef __SAMPLE_IDL__
#define __SAMPLE_IDL__

typedef sequence <octet> ByteArray;

struct ComplexType {
ByteArray data;
string info;
};

interface Sample {
void doSomething(in ComplexType value);
};

#endif // __SAMPLE_IDL__

And the following is a snippet from the client program:

ComplexType value = new ComplexType();
// leave data field to be NULL
value.info = "Hello, World! ";
xxx.doSomething(value);

If I provide an empty data field for ComplexType, it will fail to
serialize the parameter value.
And the following is part of the autogenerated class ByteArrayHelper:

public static void write (org.omg.CORBA.portable.OutputStream
ostream, byte[] value)
{
ostream.write_long (value.length);
ostream.write_octet_array (value, 0, value.length);
}

It always throws java.lang.NullPointerException at the line:
ostream.write_long (value.length);

2.If I have another method:
void echoString(in string info);

If the client call this method with a null parameter, ORB will
complain too. But sometimes, it 's reasonable requirement. Is it any
solution to this? Redefine a method:
void echoString();
or block such kind of request by client?

There must be a better solution. But what is it?

[解决办法]
好像不可以,你只能传空对象。
[解决办法]
你试一下IDL类型定义为any,调试一下java和c++分别怎么处理

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