Retrieving binary data from SQL table in JAVA with Byte array and BitSet class

Table Structure - Column X(Binary (15),null)

Value in Column X - 000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000000000000000000

i.e 15x8=120 bits

SQL query

Select X from tablename;

Java Code part 开发者_运维百科for retrieving value: barray is byte[] and bits is new BitSet().

barray = resultset.getBytes("X");

if(barray != null) {
   for (int i = 0; i < barray.length * 8; i++) {
      if ((barray[barray.length-i/8-1]&(1<<(i%8))) > 0) {
         bits.set(i);
      }
   }
}

Problem: The 2nd if statement is returning false value(not sure y?) thus the bits object is not getting populated. Please suggest a solution.

I think your mistake is outside of the code you posted, as I wrapped it in this program, and it works here:

package de.fencing_game.paul.examples;

import java.util.BitSet;

/**
 * Test class for http://stackoverflow.com/questions/5391097/retrieving-binary-data-from-sql-table-in-java-with-byte-array-and-bitset-class.
 */
public class BitSetByteArrayTest {


    public static void main(String[] params) {

        byte[] barray= new byte[]{ 0x01, 0x02, 0x04, 0x08,
                                   0x10, 0x20, 0x40, (byte)0x80,
                                   };
        BitSet bits = new BitSet();

        if(barray!=null){
            for (int i=0; i<barray.length*8; i++) {
                if ((barray[barray.length-i/8-1]&(1<<(i%8))) > 0) {
                    bits.set(i);
                }
            }
        }
        System.out.println(bits);
    }
}

It works also with your input

    byte[] barray = { 0,    0, 0, 0, 0,
                      0x20, 0, 0, 0, 0,
                      0,    0, 0, 0, 0};

instead of the sample array, showing {77} then.