blocks|key|72691|text|安迪·托马斯提到过，有一种更简单的方法可以毫无问题地将ByteBuffer解码为String。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|72692|String+s+=+StandardCharsets.UTF_8.decode(byteBuffer).toString();|code-block|syntax|javascript|72693|entityMap^0|R|A|14|6|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

There is simpler approach to decode a <code>ByteBuffer</code> into a <code>String</code> without any problems, mentioned by Andy Thomas. 

<pre><code>String s = StandardCharsets.UTF_8.decode(byteBuffer).toString();
</code></pre>

blocks|key|289854|text|试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|289855|new+String(bytebuffer.array(),+"ASCII");|code-block|syntax|javascript|289856|注意：在不知道其编码的情况下，无法正确地将字节数组转换为字符串。|289857|我希望这能帮到你|289858|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Try this:

<pre><code>new String(bytebuffer.array(), "ASCII");
</code></pre>

NB. you can't correctly convert a byte array to a String without knowing its encoding.

I hope this helps

blocks|key|72547|text|我只想指出，假设ByteBuffer.array()总是有效是不安全的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|72548|byte[]+bytes;
if(buffer.hasArray())+{
++++bytes+=+buffer.array();
}+else+{
++++bytes+=+new+byte[buffer.remaining()];
++++buffer.get(bytes);
}
String+v+=+new+String(bytes,+charset);|code-block|syntax|javascript|72549|通常，buffer.hasArray()总是真或假，这取决于您的用例。在实践中，除非你真的希望它在任何情况下都能工作，否则优化掉你不需要的分支是安全的。但是其余的答案可能不适用于通过ByteBuffer.allocateDirect()创建的ByteBuffer。|72550|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Just wanted to point out, it's not safe to assume ByteBuffer.array() will always work.

<pre><code>byte[] bytes;
if(buffer.hasArray()) {
 bytes = buffer.array();
} else {
 bytes = new byte[buffer.remaining()];
 buffer.get(bytes);
}
String v = new String(bytes, charset);
</code></pre>

Usually buffer.hasArray() will always be true or false depending on your use case. In practice, unless you really want it to work under any circumstances, it's safe to optimize away the branch you don't need. But the rest of the answers may not work with a ByteBuffer that's been created through ByteBuffer.allocateDirect().

blocks|key|289979|text|简单地调用array()的答案是不太正确的:当缓冲区已经被部分使用，或者引用了数组的一部分(您可以在给定偏移量处对数组执行ByteBuffer.wrap操作，而不一定是从开头开始)，我们必须在计算中考虑到这一点。这是在所有情况下都适用于缓冲区的通用解决方案(不包括编码)：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|289980|if+(myByteBuffer.hasArray())+{
++++return+new+String(myByteBuffer.array(),
++++++++myByteBuffer.arrayOffset()+%2B+myByteBuffer.position(),
++++++++myByteBuffer.remaining());
}+else+{
++++final+byte[]+b+=+new+byte[myByteBuffer.remaining()];
++++myByteBuffer.duplicate().get(b);
++++return+new+String(b);
}|code-block|syntax|javascript|289981|有关编码方面的问题，请参阅Andy+Thomas的答案。|289982|entityMap^0|5|7|1P|F|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

The answers referring to simply calling <code>array()</code> are not quite correct: when the buffer has been partially consumed, or is referring to a part of an array (you can <code>ByteBuffer.wrap</code> an array at a given offset, not necessarily from the beginning), we have to account for that in our calculations. This is the general solution that works for buffers in all cases (does not cover encoding):

<pre><code>if (myByteBuffer.hasArray()) {
 return new String(myByteBuffer.array(),
 myByteBuffer.arrayOffset() + myByteBuffer.position(),
 myByteBuffer.remaining());
} else {
 final byte[] b = new byte[myByteBuffer.remaining()];
 myByteBuffer.duplicate().get(b);
 return new String(b);
}
</code></pre>

For the concerns related to encoding, see Andy Thomas' answer.

blocks|key|289927|text|请注意(除了编码问题)，一些更复杂的代码链接会遇到获取ByteBuffer的“活动”部分的麻烦(例如，通过使用位置和限制)，而不是简单地编码整个后备数组中的所有字节(正如这些答案中的许多示例所做的那样)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|289928|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|$]]

Notice (aside from the encoding issue) that some of the more complicated code linked goes to the trouble of getting the "active" portion of the ByteBuffer in question (for example by using position and limit), rather than simply encoding all of the bytes in the entire backing array (as many of the examples in these answers do).

blocks|key|290052|text|private+String+convertFrom(String+lines,+String+from,+String+to)+{
++++ByteBuffer+bb+=+ByteBuffer.wrap(lines.getBytes());
++++CharBuffer+cb+=+Charset.forName(to).decode(bb);
++++return+new+String(Charset.forName(from).encode(cb).array());
};
public+Doit(){
++++String+concatenatedLines+=+convertFrom(concatenatedLines,+"CP1252",+"UTF-8");
};|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|290053|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>private String convertFrom(String lines, String from, String to) {
 ByteBuffer bb = ByteBuffer.wrap(lines.getBytes());
 CharBuffer cb = Charset.forName(to).decode(bb);
 return new String(Charset.forName(from).encode(cb).array());
};
public Doit(){
 String concatenatedLines = convertFrom(concatenatedLines, "CP1252", "UTF-8");
};
</code></pre>

blocks|key|72747|text|下面是一个将字节缓冲区转换为字符串的简单函数：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|72748|public+String+byteBufferToString(ByteBuffer+bufferData)+{
++++byte[]+buffer+=+new+byte[bufferData.readableByteCount()];
++++//+read+bufferData+and+insert+into+buffer+
++++data.read(buffer);
++++//+CharsetUtil+supports+UTF_16,+ASCII,+and+many+more
++++String+text+=+new+String(buffer,+CharsetUtil.UTF_8);
++++System.out.println("Text:+"%2Btext);
++++return+text;
}|code-block|syntax|javascript|72749|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here is a simple function for converting a byte buffer to string:
<pre><code>public String byteBufferToString(ByteBuffer bufferData) {
 byte[] buffer = new byte[bufferData.readableByteCount()];
 // read bufferData and insert into buffer 
 data.read(buffer);
 // CharsetUtil supports UTF_16, ASCII, and many more
 String text = new String(buffer, CharsetUtil.UTF_8);
 System.out.println(&quot;Text: &quot;+text);
 return text;
}
</code></pre>

blocks|key|290161|text|这是我在java.nio.ByteBuffer实例上唯一有效的方法：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|290162|String+fileContent+=+new+String(bb.array(),+StandardCharsets.UTF_8);|290163|相关代码片段如下：|290164|import+java.nio.file.Path;
import+java.nio.file.Paths;
import+java.nio.channels.FileChannel;
import+java.nio.ByteBuffer;


Path+path+=+Paths.get("/home/binita/testbb");
FileChannel+fileChannel+=+FileChannel.open(path,+
+++++++++++++++++EnumSet.of(StandardOpenOption.READ
++++++++++++++++++++)
+++++++++++++++++);++
++++++++++++
ByteBuffer+bb+=+ByteBuffer.allocate(1024);
int+bytesRead+=+fileChannel.read(bb);
if(bytesRead+>+0)+{
+String+fileContent+=+new+String(bb.array(),+StandardCharsets.UTF_8);
}|code-block|syntax|javascript|290165|entityMap^0|4|J|0|0|1W|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|T|8|@$9|U|A|V|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|W|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|X|8|@]|D|@]|E|$M|N]]|$1|O|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|P|$]]

This was the only method that worked for me on a <code>java.nio.ByteBuffer</code> instance:
<code>String fileContent = new String(bb.array(), StandardCharsets.UTF_8);</code>
Related code snippet below:
<pre><code>import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.channels.FileChannel;
import java.nio.ByteBuffer;


Path path = Paths.get(&quot;/home/binita/testbb&quot;);
FileChannel fileChannel = FileChannel.open(path, 
 EnumSet.of(StandardOpenOption.READ
 )
 ); 
 
ByteBuffer bb = ByteBuffer.allocate(1024);
int bytesRead = fileChannel.read(bb);
if(bytesRead &gt; 0) {
 String fileContent = new String(bb.array(), StandardCharsets.UTF_8);
}
</code></pre>

Is this a correct approach to convert ByteBuffer to String in this way,

<pre><code>String k = "abcd";
ByteBuffer b = ByteBuffer.wrap(k.getBytes());
String v = new String(b.array());

if(k.equals(v))
 System.out.println("it worked");
else
 System.out.println("did not work");
</code></pre>

The reason I ask is that is this looks too simple, whereas other approaches like <a href="https://stackoverflow.com/questions/1252468/java-converting-string-to-and-from-bytebuffer-and-associated-problems">Java: Converting String to and from ByteBuffer and associated problems</a> looks more complex.

Java ByteBuffer to String

以这种方式将ByteBuffer转换为字符串是正确方法吗，String k = "abcd";ByteBuffer b = ByteBuffer.wrap(k.getBytes());String v = new String(b.array());if(k.equals(v))    System.out.println("it worked");else    System.out.print

问Java ByteBuffer to String
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