处理InputStream并写入OuputStream，并确保这两个流都关闭

Question

在单个最后块中执行多个文件关闭是一件坏事吗？

有关摘录：

BufferedInputStream inStream;
BufferedOutputStream destStream;
try {
    inStream = new BufferedInputStream(/*...*/);
    destStream = new BufferedOutputStream(/*...*/);
    // ... reading from file
    // ... processing
    // ... writting to file
    destStream.flush();
} catch (Exception e) {
    Log("ERROR: " + e.getMessage());
} finally {
    try { destStream.close(); } catch (Exception ignored) {}
    try { inStream.close(); } catch (Exception ignored) {}
}

编辑-1:我不能使用java7 (所以我不能使用来自java7的try-with ) :(

Answer 1

正如Nolequen所写的，他的选择更适合使用。但这是7+中才有可能只有在

如果您想继续执行您的解决方案，您可以创建一个尝试并将其放入内部。

    try {
        BufferedInputStream inStream = new BufferedInputStream(/*...*/);
        BufferedOutputStream destStream = new BufferedOutputStream(/*...*/);
        // ... reading from file
        // ... processing
        // ... writting to file
        destStream.flush();
    } catch (Exception e) {
        Log("ERROR: " + e.getMessage());
    } finally {
        try { 
            destStream.close(); 
            inStream.close();
        } catch (Exception ignored) {}
}

Answer 2

最好使用试着用资源语句。因此，您不需要手动关闭流：

try (final BufferedInputStream inStream = new BufferedInputStream(/*...*/);
     final BufferedOutputStream destStream = new BufferedOutputStream(/*...*/)) {
    //do some work
} catch (Exception e) {
    Log("ERROR: " + e.getMessage());
}

Answer 3

InputStream和OutputStream都在Java6中实现了Closable接口，这样您就可以编写自己的异常，以规范更接近的对象/方法：

private void closeIgnoringException(Closable closable){
     try { closable.close(); } 
     catch (Exception ignored) {
       ignored.printStacktrace();
     }
}

Set<Closable> closables = new HasSet<Closable>();  
try {
    BufferedInputStream inStream = new BufferedInputStream(/*...*/);
    closables.add(inStream);
    BufferedOutputStream destStream = new BufferedOutputStream(/*...*/);
    closables.add(destStream );
    // ... reading from file
    // ... processing
    // ... writting to file
    destStream.flush();
} catch (Exception e) {
    Log("ERROR: " + e.getMessage());
} finally {
    for(Closable closable : closables)
       closeIgnoringException(closable );
}