我正在使用axis2来提供一个基本的Web服务,它将获取文件名作为参数,并生成一个响应SOAP数据包,该数据包将随SOAP一起附加文件.

这是我创建服务代码的方式(它的简单和灵感来自Axis2示例代码)

public String getFile(String name) throws IOException
{
MessageContext msgCtx = MessageContext.getCurrentMessageContext();
File file = new File (name);
System.out.println("File = " + name);
System.out.println("File exists = " + file.exists());
FileDataSource fileDataSource = new FileDataSource(file);
System.out.println("fileDataSource = " + fileDataSource);
DataHandler dataHandler = new DataHandler(fileDataSource);
System.out.println("DataHandler = " + dataHandler);
    String attachmentID = msgCtx.addAttachment(dataHandler);
    System.out.println("attachment ID = " + attachmentID);
    return attachmentID;
}

现在客户端代码 –

      MessageContext response = mepClient
            .getMessageContext(WSDLConstants.MESSAGE_LABEL_IN_VALUE);
    SOAPBody body = response.getEnvelope().getBody();
    OMElement element = body.getFirstElement().getFirstChildWithName(
    new QName("http://service.soapwithattachments.sample","return"));
    String attachementId = element.getText();
    System.out.println("attachment id is " + attachementId);
    Attachments attachment = response.getAttachmentMap();
        DataHandler dataHandler = attachment.getDataHandler(attachementId);

问题是dataHandler始终为null.虽然我认为在服务器端,文件已被读取并与SOAP数据包一起附加.难道我做错了什么 ？

编辑：
我把< parameter name =“enableSwA”locked =“false”> true< / parameter>在axis2.xml文件中.

解决方法:

我找到了这个问题的解决方案.
问题是,在服务器端,使用MessageContext msgCtx = MessageContext.getCurrentMessageContext(); call,我们得到传入消息上下文的句柄.我在传入的消息上下文中添加了附件,而附件需要添加到传出消息上下文中.
要获取传出消息上下文的句柄,需要执行以下步骤 –

   //this is the incoming message context
    MessageContext inMessageContext  = MessageContext.getCurrentMessageContext();
    OperationContext operationContext = inMessageContext.getOperationContext();
    //this is the outgoing message context
    MessageContext outMessageContext =     operationContext.getMessageContext(WSDLConstants.MESSAGE_LABEL_OUT_VALUE);

收到传出消息上下文后,在此处添加附件 –

String attachmentID = outMessageContext.addAttachment(dataHandler);

其余代码保持不变.

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