Java Byte Array Conversion

Dec 24, 2016

This is a small class to convert a byte array to short and int, faster than with a ByteBuffer.

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public class Convert {
    // byte to "unsigned int"
    // this is needed because there is are no unsigned types in java
    public static int BToUI(byte b) {
        return ((int) b) & 0XFF;
    }
    // byte to short
    public static short BAToS(byte b[]) {
        return BAToS(b, 0);
    }
    // byte to short with an offset in the byte array
    public static short BAToS(byte b[], int offset) {
        return (short) (((b[offset + 1] & 0xFF) << 8) | (b[offset] & 0xFF));
    }
    // byte array to an integer
    public static int BAToI(byte b[]) {
        return BAToI(b, 0);
    }
    // byte array to an integer with an offset
    public static int BAToI(byte b[], int offset) {
        return ((b[offset + 3] & 0xFF) << 24) |
                ((b[offset + 2] & 0xFF) << 16) |
                ((b[offset + 1] & 0xFF) << 8)  |
                (b[offset] & 0xFF);
    }
    
    // byte array to float
    public static float BAToF(byte b[]) {
        return Float.intBitsToFloat(BAToI(b));
    }
}