There are many ways to create a ByteBuffer:

• Create a ByteBuffer using an existing array

byte[] bytes = new byte[BUFFER_SIZE];
ByteBuffer buffer = ByteBuffer.wrap(bytes);

• Create a non-direct ByteBuffer with a specific byte capacity

ByteBuffer buffer = ByteBuffer.allocate(10);

• Create a direct ByteBuffer with a specific byte capacity

ByteBuffer buffer = ByteBuffer.allocateDirect(10);

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