BitUtil.java

package com.hypixel.hytale.common.util;

import javax.annotation.Nonnull;

public class BitUtil {
   public BitUtil() {
   }

   public static void setNibble(@Nonnull byte[] data, int idx, byte b) {
      int fieldIdx = idx >> 1;
      byte val = data[fieldIdx];
      b = (byte)(b & 15);
      int i = idx & 1;
      b = (byte)(b << ((i ^ 1) << 2));
      val = (byte)(val & 15 << (i << 2));
      val = (byte)(val | b);
      data[fieldIdx] = val;
   }

   public static byte getNibble(@Nonnull byte[] data, int idx) {
      int   idx >> ;
         data[fieldIdx];
         idx & ;
      val = ()(val >> ((i ^ ) << ));
      val = ()(val & );
       val;
   }

       {
         idx >> ;
         data[fieldIdx];
         idx & ;
         ()(val >> ((i ^ ) << ));
      oldVal = ()(oldVal & );
      b = ()(b & );
      b = ()(b << ((i ^ ) << ));
      val = ()(val &  << (i << ));
      val = ()(val | b);
      data[fieldIdx] = val;
       oldVal;
   }
}