java - 发生异常后如何关闭 BufferedReader？

Question

以简单代码为例:

            FileInputStream fis = null;
            BufferedReader dr = null;
            try{
                fis = new FileInputStream("D:\\acc_cp.log");
                dr = new BufferedReader(new InputStreamReader(fis));
                producer = new LogProducer(); // it may throw an exception
                String line = "";
                while((line = dr.readLine())!= null ){ // readline may throw an exception too
                     producer.send("test", line);
                     Thread.sleep(50);
                }
            }catch(Exception e){
                e.printStackTrace();
            }finally{
                if(producer != null){
                    producer.close(); 
                }
            }

两者producer = new LogProducer();和(line = dr.readLine())可能会抛出异常。所以，我的问题是，如果 producer = new LogProducer();抛出异常，我想正确关闭 BufferedReader，合适的方法是什么？ 如果我输入 dr.close()在catch子句或finally子句中，它迫使我再次抛出异常，显然这不是一个好的解决方案。

Answer 1

您可以按照当前关闭生产者(在finally block 中)的方式执行此操作(如果您不想重新启动，则添加一个try-catch -抛出IOException)就像

} finally {
    if(producer != null){
        producer.close(); 
    }
    if(dr != null) {
        try {
            dr.close();
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
    }
}

或者，您可以使用try-with-resources statement 关闭就像

try (FileInputStream fis = new FileInputStream("D:\\acc_cp.log");
    BufferedReader dr = new BufferedReader(new InputStreamReader(fis));
    LogProducer producer = new LogProducer()) {
    // ...