close()方法应该在finally语句中调用吗?

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下面列出了关闭输出流(output writer) 的三种不同方式.

第一种是将close()方法调用置于try语句块内部;

//close() is in try clause
try {
  PrintWriter out = new PrintWriter(
      new BufferedWriter(
      new FileWriter("out.txt", true)));
  out.println("the text");
  out.close();
} catch (IOException e) {
  e.printStackTrace();
}

第二种是将close()方法调用置于finally语句块中;

//close() is in finally clause
PrintWriter out = null;
try {
  out = new PrintWriter(
    new BufferedWriter(
    new FileWriter("out.txt", true)));
  out.println("the text");
} catch (IOException e) {
  e.printStackTrace();
} finally {
  if (out != null) {
    out.close();
  }
}

第三种是使用从Java 7 开始引进的 try-with-resources方式;

//Java 7, try-with-resource statement
try (PrintWriter out2 = new PrintWriter(
      new BufferedWriter(
      new FileWriter("out.txt", true)))) {
  out2.println("the text");
} catch (IOException e) {
  e.printStackTrace();
}

哪一种是最好的方式呢?

有一定编程经验的开发者都知道,不论何种情况下(不管有没有异常发生), 输出流都应该被关闭,所以 close()方法应该在 finally块中调用。