Operators

package demo;

public class App {
  public static void main( String[] args ) {
    /* String concatenation */
    {
      int a = 7;
      int b = 3;
      String m = "The number is " + a + b;
      String n = "The number is " + ( a + b );
      String o = a + b + " is the number";
      System.out.println( "-- String concatenation ----" );
      System.out.printf( "Concatenation:   %s%n", m );
      System.out.printf( "Grouping before: %s%n", n );
      System.out.printf( "Adding before:   %s%n", o );
    }

    /* Basic Arithmetic */
    {
      int a = 2;
      int b = 2;
      int c = a + b + 2;
      int d = a++;
      int e = ++b;

      int f = 1 / 2;
      int g = 1 % 2;
      int h = -1 % 2;

      System.out.println( "-- Basic Arithmetic ----------" );
      System.out.printf( "a = %d%n", a );
      System.out.printf( "b = %d%n", b );
      System.out.printf( "a + b + 2 = %d%n", c );
      System.out.printf( "a++ = %d%n", d );
      System.out.printf( "++b = %d%n", e );
      System.out.printf( "1 / 2 = %d%n", f );
      System.out.printf( "1 %% 2 = %d%n", g );
      System.out.printf( "1- %% 2 = %d%n", h );
    }

    /* Arithmetic operations return an int (or long) */
    {
      byte a = 7;
      byte b = 3;
      int plus = a + b;
      int minus = a - b;
      byte c = 7;
      c += b;
      System.out.println( "-- Arithmetic operations ---" );
      System.out.printf( "a + b = %d%n", plus );
      System.out.printf( "a - b = %d%n", minus );
      System.out.printf( "c = %d%n", c );
    }

    /* Relational operators */
    {
      boolean a = 2 > 1;
      boolean b = 2 != 2;
      boolean c = a && b;
      boolean d = a || b;
      boolean e = !a;

      System.out.println( "-- Relational operators ---" );
      System.out.printf( "2 > 1 = %s%n", a );
      System.out.printf( "2 != 2 = %s%n", b );
      System.out.printf( "%s && %s = %s%n", a, b, c );
      System.out.printf( "%s || %s = %s%n", a, b, d );
      System.out.printf( "!%s = %s%n", a, e );
    }
  }
}