Does anyone know how to convert ByteBuffer to byte[] array? I need to get byte array from my ByteBuffer. When I run bytebuffer.hasArray() it returns no. Every question I looked so far is converting byte array to byteBuffer, but I need it other way around.
Thank you.
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Axel Fontaine
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Powisss
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2Have you tried `byteBuffer.array()`? – Johnny Willer Feb 26 '15 at 13:50
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1@JohnnyWiller - it will fail ... hasArray is returning `false`. – Stephen C Feb 26 '15 at 13:55
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Yes i did with no success. – Powisss Feb 26 '15 at 13:55
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Ok.. I think nomis's answer will work :) – Johnny Willer Feb 26 '15 at 13:56
2 Answers
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ByteBuffer exposes the bulk get(byte[]) method which transfers bytes from the buffer into the array. You'll need to instantiate an array of length equal to the number of remaining bytes in the buffer.
ByteBuffer buf = ...
byte[] arr = new byte[buf.remaining()];
buf.get(arr);
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Code only anwers are normally improved by adding some text explaining what the code is doing - can you add a bit of text to explain to the OP? – J Richard Snape Feb 26 '15 at 14:13
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9don't forget to call `buf.rewind()`, otherwise `buf.remaining()` will return with incorrect value – BoygeniusDexter Jun 04 '18 at 14:00
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hi, buf.get(arr) still returns a ByteBuffer, is there any other alternative? – jpganz18 Mar 03 '20 at 14:48
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This is not converting the ByteBuffer to byte array. Its still returning ByteBuffer. – Seetharamani Tmr Mar 20 '20 at 19:55
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4@SeetharamaniTmr - The bytes are being filled into "arr" variable and are not the returned value. – gioravered Apr 12 '20 at 08:58
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`byte[] arr = new byte[ buf.position() ]; buf.rewind(); buf.get(arr)` – Grigory K Jul 30 '21 at 11:47
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If hasArray() reports false then, calling array() will throw an exception.
In that case, the only way to get the data in a byte[] is to allocate a byte[] and copy the bytes to the byte[] using get(byte) or similar.
Stephen C
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