java - 在这里使用@lombok.Cleanup的正确方法是什么？

Question

之前的代码是这样的 -

    try {
         some other code
         ......
         ......
            ByteArrayInputStream annoBais = new ByteArrayInputStream(annoBytes);
            DataInputStream dis = new DataInputStream(annoBais);
            InputStream annoStream = dis;
            inputRecord.put("XMLStream", annoStream);
            MappedRecord resultMappedRecord = (MappedRecord)interaction.execute(interactionSpec,inputRecord);
            HashMap mappedAnnotIds =  (HashMap)resultMappedRecord.get(("ResultHashMap").toString());
            annoStream.close(); //closed here
            annoBais.close();   // closed here
            dis.close();     // closed here
         ......
         ......
         some more code 
        }

我把它改为-

 try {
some other code
......
......                
@lombok.Cleanup ByteArrayInputStream annoBais = new ByteArrayInputStream(annoBytes);
@lombok.Cleanup DataInputStream dis = new DataInputStream(annoBais);
@lombok.Cleanup InputStream annoStream = dis; 
inputRecord.put("XMLStream", annoStream);
MappedRecord resultMappedRecord (MappedRecord)interaction.execute(interactionSpec,inputRecord);
HashMap mappedAnnotIds = (HashMap)resultMappedRecord.get(("ResultHashMap").toString());
......
......
some more code 
}

@lombok.Cleanup 是否具有相同的范围？它会在先前手动关闭的同一位置关闭吗？如果不是，我怎样才能以仍然具有相同范围的方式关闭它？

Answer 1

这里使用@lombok.Cleanup的正确方法是不使用lombok； Java7 通过 try with resources 解决了这个问题.

例如，使用您的代码:

     some other code
     ......
     ......

     try (  ByteArrayInputStream annoBais = new ByteArrayInputStream(annoBytes);
            DataInputStream dis = new DataInputStream(annoBais) ) {
        InputStream annoStream = dis;
        inputRecord.put("XMLStream", annoStream);
        MappedRecord resultMappedRecord = (MappedRecord)interaction.execute(interactionSpec,inputRecord);
        HashMap mappedAnnotIds =  (HashMap)resultMappedRecord.get(("ResultHashMap").toString());
     }
     //  annoBais & dis get closed here.
     //  Note: annoStream is an alias of dis, not a separate resource.
     ......
     ......
     some more code 

当然，这段代码需要被 try {} catch () {} block 包围，或者您的方法必须声明它抛出所需的异常。

使用“尝试使用资源”不会导致您必须处理其他异常。您始终需要处理所有已检查的异常，方法是捕获它们或声明您的方法抛出它们。