e158. creating a bytebuffer.txt

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A ByteBuffer is a fixed-capacity buffer that holds byte values. This example demonstrates a number of ways to create a ByteBuffer. 
See also e159 Getting Bytes from a ByteBuffer and e160 Putting Bytes into a ByteBuffer. 

    // Create a ByteBuffer using a byte array
    byte[] bytes = new byte[10];
    ByteBuffer buf = ByteBuffer.wrap(bytes);
    
    // Create a non-direct ByteBuffer with a 10 byte capacity
    // The underlying storage is a byte array.
    buf = ByteBuffer.allocate(10);
    
    // Create a direct (memory-mapped) ByteBuffer with a 10 byte capacity.
    buf = ByteBuffer.allocateDirect(10);
    
    // To create a ByteBuffer for a memory-mapped file,
    // see e166 Creating a Memory-Mapped File