blocks|key|1244800|text|BufferedReader的源代码显示，当您关闭BufferedReader时，底层是关闭的。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1244801|entityMap|0|LINK|mutability|MUTABLE|url|http://www.docjar.com/html/api/java/io/BufferedReader.java.html^0|0|E|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

The source code for <a href="http://www.docjar.com/html/api/java/io/BufferedReader.java.html" rel="noreferrer">BufferedReader</a> shows that the underlying is closed when you close the BufferedReader.

blocks|key|1459474|text|根据BufferedReader来源的说法，在这种情况下，bReader.close调用fReader.close，因此从技术上讲，您不必调用后者。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1459475|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

According to BufferedReader source, in this case bReader.close call fReader.close so technically you do not have to call the latter.

blocks|key|1459637|text|从Java7开始，您可以使用try-with-resources+Statement|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1459638|try+(BufferedReader+br+=+new+BufferedReader(new+FileReader(path)))+{
++++return+br.readLine();
}|code-block|syntax|javascript|1459639|因为BufferedReader实例是在try-with-resource语句中声明的，所以无论try语句是正常完成还是突然完成，它都将被关闭。因此，您不需要在finally语句中自己关闭它。(嵌套资源语句也是如此)|style|CODE|1459640|这是推荐的使用资源的方法，有关详细信息，请参阅documentation|1459641|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html|1^0|E|S|0|0|0|2|E|28|7|0|N|D|1|0^^$0|@$1|2|3|4|5|6|7|X|8|@]|9|@$A|Y|B|Z|1|10]]|C|$]]|$1|D|3|E|5|F|7|11|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|12|8|@$A|13|B|14|K|L]|$A|15|B|16|K|L]]|9|@]|C|$]]|$1|M|3|N|5|6|7|17|8|@]|9|@$A|18|B|19|1|1A]]|C|$]]|$1|O|3|-4|5|6|7|1B|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]|W|$5|R|S|T|C|$U|V]]]]

Starting from Java 7 you can use <a href="https://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html" rel="nofollow noreferrer">try-with-resources Statement</a>

<pre><code>try (BufferedReader br = new BufferedReader(new FileReader(path))) {
 return br.readLine();
}
</code></pre>

Because the <code>BufferedReader</code> instance is declared in a try-with-resource statement, it will be closed regardless of whether the try statement completes normally or abruptly. So you don't need to close it yourself in the <code>finally</code> statement. (This is also the case with nested resource statements)

This is the recomanded way to work with resources, see the <a href="https://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html" rel="nofollow noreferrer">documentation</a> for more detailed information

blocks|key|1244858|text|您只需关闭bufferedReader+(即reader.close()+)，它就会正常工作。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1244859|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

You Only Need to close the bufferedReader i.e reader.close() and it will work fine .

blocks|key|1244968|text|我来晚了，但是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1244969|BufferReader.java：|1244970|public+BufferedReader(Reader+in)+{
++this(in,+defaultCharBufferSize);
}

(...)

public+void+close()+throws+IOException+{
++++synchronized+(lock)+{
++++++++if+(in+==+null)
++++++++++++return;
++++++++try+{
++++++++++++in.close();
++++++++}+finally+{
++++++++++++in+=+null;
++++++++++++cb+=+null;
++++++++}
++++}
}|code-block|syntax|javascript|1244971|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I'm late, but:

BufferReader.java:

<pre><code>public BufferedReader(Reader in) {
 this(in, defaultCharBufferSize);
}

(...)

public void close() throws IOException {
 synchronized (lock) {
 if (in == null)
 return;
 try {
 in.close();
 } finally {
 in = null;
 cb = null;
 }
 }
}
</code></pre>

blocks|key|1245040|text|在您的场景中，您只需要关闭BufferedReader。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1245041|正如其他人所指出的，JavaDocs是模棱两可的。当您希望立即调用close时，使用try-with-resources块是最好的方法，但如果您需要保持读取器的打开状态(例如，一个类具有返回使用底层读取器的流的方法--在那里调用close通常是调用者的责任)，那么它就不起作用。|1245042|如果您无法访问源代码，并且希望查看您的阅读器和JVM是否在各种阅读器和流上调用close，则可以将close方法作为一种简单的测试进行覆盖。|1245043|Path+path+=+Paths.get("/home/example/test.txt");

InputStream+fileInputStream+=+new+FileInputStream(path.toFile())+{
++++public+void+close()+throws+IOException+{
++++++++System.out.println("FileInputStream::close()");
++++++++super.close();
++++}
};
Reader+inputStreamReader+=+new+InputStreamReader(fileInputStream,+Charsets.UTF_8)+{
++++public+void+close()+throws+IOException+{
++++++++System.out.println("InputStreamReader::close()");
++++++++super.close();
++++}
};
BufferedReader+bufferedReader+=+new+BufferedReader(inputStreamReader)+{
++++public+void+close()+throws+IOException+{
++++++++System.out.println("BufferedReader::close()");
++++++++super.close();
++++}
};

bufferedReader.close();|code-block|syntax|javascript|1245044|当你运行上面的代码时，你会看到类似的东西：|1245045|BufferedReader::close()
InputStreamReader::close()
FileInputStream::close()|1245046|由于在JavaDoc中没有明确的规范，我们不能确定所有JVM的行为。然而，大多数读取器/流似乎都遵循上面的模式(例如，你可以在上面的例子中添加一个GZIPInputStream，然后看到GZIPInputStream::close()也会被调用)。|1245047|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/10/docs/api/java/io/Reader.html#close()^0|D|E|0|X|5|36|5|A|8|0|0|13|5|1D|5|0|0|0|0|21|F|2L|O|0^^$0|@$1|2|3|4|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|15|8|@$9|16|A|17|B|C]|$9|18|A|19|B|C]]|D|@$9|1A|A|1B|1|1C]]|E|$]]|$1|H|3|I|5|6|7|1D|8|@$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]]|D|@]|E|$]]|$1|J|3|K|5|L|7|1I|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|1J|8|@]|D|@]|E|$]]|$1|Q|3|R|5|L|7|1K|8|@]|D|@]|E|$M|N]]|$1|S|3|T|5|6|7|1L|8|@$9|1M|A|1N|B|C]|$9|1O|A|1P|B|C]]|D|@]|E|$]]|$1|U|3|-4|5|6|7|1Q|8|@]|D|@]|E|$]]]|V|$W|$5|X|Y|Z|E|$10|11]]]]

You need to close only the <code>BufferedReader</code> in your scenario.
As others have pointed out, the <a href="https://docs.oracle.com/javase/10/docs/api/java/io/Reader.html#close()" rel="nofollow noreferrer">JavaDocs</a> are ambiguous. Using the try-with-resources block is the best approach when you want <code>close</code> to be called right away, but it doesn't work if you need to keep the reader open (e.g. a class that has a method that returns a stream which uses an underlying reader--it would generally be the caller's responsibility to call <code>close</code> there).
If you don't have access to the source code and want to see whether your reader and JVM calls <code>close</code> on the various readers and streams in your situation, you could override the <code>close</code> method as a simple test.
<pre><code>Path path = Paths.get(&quot;/home/example/test.txt&quot;);

InputStream fileInputStream = new FileInputStream(path.toFile()) {
 public void close() throws IOException {
 System.out.println(&quot;FileInputStream::close()&quot;);
 super.close();
 }
};
Reader inputStreamReader = new InputStreamReader(fileInputStream, Charsets.UTF_8) {
 public void close() throws IOException {
 System.out.println(&quot;InputStreamReader::close()&quot;);
 super.close();
 }
};
BufferedReader bufferedReader = new BufferedReader(inputStreamReader) {
 public void close() throws IOException {
 System.out.println(&quot;BufferedReader::close()&quot;);
 super.close();
 }
};

bufferedReader.close();
</code></pre>
When you run the above, you'll see something very similar to:
<pre><code>BufferedReader::close()
InputStreamReader::close()
FileInputStream::close()
</code></pre>
Since there is no explicit specification written in the JavaDoc, we can't be certain of the behavior across all JVMs. However, most of readers/streams seem to follow the above pattern (e.g. you can add a <code>GZIPInputStream</code> to the above example and see that <code>GZIPInputStream::close()</code> also gets called).

I'm reading a local file using a BufferedReader wrapped around a FileReader:

<pre><code>BufferedReader reader = new BufferedReader(new FileReader(fileName));
// read the file
// (error handling snipped)
reader.close();
</code></pre>

Do I need to <code>close()</code> the <code>FileReader</code> as well, or will the wrapper handle that?
I've seen code where people do something like this:

<pre><code>FileReader fReader = new FileReader(fileName);
BufferedReader bReader = new BufferedReader(fReader);
// read the file
// (error handling snipped)
bReader.close();
fReader.close();
</code></pre>

This method is called from a servlet, and I'd like to make sure I don't leave any handles open.

Do I need to close() both FileReader and BufferedReader?

我正在使用包装在FileReader周围的BufferedReader读取本地文件：BufferedReader reader = new BufferedReader(new FileReader(fileName));// read the file// (error handling snipped)reader.close();我是否也需要对FileReader执行close()操作，或者

问我需要同时关闭FileReader和BufferedReader ()吗？
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问我需要同时关闭FileReader和BufferedReader ()吗？
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