CODEWITHSUNDEEP
java
Volatil3
Volatil3

Reputation: 14978

Java Array Initialization at runtime

I am working on Java based COM program, when I send data in this format so it works:

serialPort.writeBytes( new byte[] { (byte)3, (byte)0, (byte)0, 
                                    (byte)0, (byte)4, (byte)5} );

but when I do following so it does not, where am I doing wrong?

byte[] bcode = null;
bcode[0] = (byte)3;
bcode[1] = (byte)0;
bcode[2] = (byte)0;
bcode[3] = (byte)0;
bcode[4] = (byte)4;
bcode[5] = (byte)5;
serialPort.writeBytes(bcode);

Upvotes: 0

Views: 656

Answers (1)

rgettman
rgettman

Reputation: 178243

On the second example, you did not create your array, you assigned it null. You can't reference an array element of an array that doesn't exist. You could do

byte[] bcode = new byte[6];

That will create your array with space for 6 bytes. Then assign your values individually.

Upvotes: 6

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