int i = 42;
   String str = Integer.toString(i);
   or
   String str = "" + i

   String str = Double.toString(i);

   String str = Long.toString(l);

   String str = Float.toString(f);

   str = "25";
   int i = Integer.valueOf(str).intValue();
   or
   int i = Integer.parseInt(str);

   double d = Double.valueOf(str).doubleValue();

   long l = Long.valueOf(str).longValue();
   or
   long l = Long.parseLong(str);

   float f = Float.valueOf(str).floatValue();

   int i = 42;
   String binstr = Integer.toBinaryString(i);

   int i = 42;
   String hexstr = Integer.toString(i, 16);

   or
   String hexstr = Integer.toHexString(i);

   or (with leading zeroes and uppercase)
   public class Hex {
     public static void main(String args[]){
       int i = 42;
       System.out.print
         (Integer.toHexString( 0x10000 | i).substring(1).toUpperCase());
      }
     }
                

   int i = Integer.valueOf("B8DA3", 16).intValue();
   or
   int i = Integer.parseInt("B8DA3", 16);     

   int i = 64;
   String aChar = new Character((char)i).toString();

   char c = 'A';
   int i = (int) c; // i will have the value 65 decimal

     String test = "ABCD";
     for ( int i = 0; i < test.length(); ++i ) {
       char c = test.charAt( i );
       int j = (int) c;
       System.out.println(j);
       }

   b = (i != 0);

   i = (b)?1:0;

try{
  i = Integer.parseInt(aString);
  }
catch(NumberFormatException e)
  {
  }