在没有 try/catch 块的情况下关闭 InputStream？

Question

我知道 InputStream 应该关闭。但我有些疑问在哪里以及如何做到这一点。

Unconditionally close an InputStream. Equivalent to InputStream.close(), except any exceptions will be ignored. This is typically used in finally blocks.

我的代码中不需要 try/catch 块，所以我没有 finally 块。在下面的方法中返回之前关闭 InputStream 是否可以，还是我应该做一些不同的事情？多个服务将使用此方法从文件加载 InputStream。

public InputStream read(String filename) {
    InputStream inputStream = Thread.currentThread().getContextClassLoader().getResourceAsStream(filename);

    if (inputStream == null) {
      // Throw some exception
    }

    IOUtils.closeQuietly(inputStream);

    return inputStream;
}

Answer 1

您根本不应该在此方法中调用 IOUtils.closeQuietly(inputStream); - 返回已关闭的流没有什么意义。

但是，这个方法应该在try/finally块中调用：

InputStream is = null;
try {
  is = read(filename);
  // Do whatever with is.
} finally {
  IOUtils.closeQuietly(is);
}

或使用 try-with-resources（注意 "try-with-resources statement will eliminate most needs for using IOUtils.closeQuietly" 的评论 here）：

try (InputStream is = read(filename)) {
  // Do whatever with is.
}

Answer 2

try/finally块：

InputStream is = null; try { InputStream is = is = read(filename); // Do whatever with is. } finally { is.close(); }

注意：所有 i/o 资源都需要在 finally 块中关闭，因为它是在 try-catch 块中初始化的。还建议加上：

} catch(IOException e){
   e.printstacktrace();
}

...用于异常处理

在没有 try/catch 块的情况下关闭 InputStream？

Closing InputStream without a try/catch block?

java

inputstream