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package algs11;
public class XAutoboxingValueOf {
  public static String concat(String s, String t) {
    return (s + t);
  }
  public static void main (String[] args) {
    {
      System.out.print ("\nString Dog:    ");
      String x1 = "Dog";
      String x2 = "Dog";
      String x3 = new String ("Dog");
      String x4 = new String ("Dog");

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      String x3i = x3.intern ();
      String x4i = x4.intern ();
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nString ...:    ");
      String x1 = "Antidisestablishmentarianism";
      String x2 = "Antidisestablishmentarianism";
      String x3 = new String ("Antidisestablishmentarianism");
      String x4 = new String ("Antidisestablishmentarianism");

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      String x3i = x3.intern ();
      String x4i = x4.intern ();
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nString + :     ");
      String x1 = "hi" + "mom";
      String x2 = "hi" + "mom";
      String x3 = new String ("hi" + "mom");
      String x4 = new String ("hi" + "mom");

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      String x3i = x3.intern ();
      String x4i = x4.intern ();
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nString concat: ");
      String x1 = concat ("hi", "mom");
      String x2 = concat ("hi", "mom");
      String x3 = new String (concat ("hi", "mom"));
      String x4 = new String (concat ("hi", "mom"));

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      String x3i = x3.intern ();
      String x4i = x4.intern ();
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nCharacter a:   ");
      Character x1 = 'a';
      Character x2 = 'a';
      Character x3 = new Character ('a');
      Character x4 = new Character ('a');

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      Character x3i = Character.valueOf (x3);
      Character x4i = Character.valueOf (x4);
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nCharacter \u13A7:   ");
      Character x1 = '\u13A7';
      Character x2 = '\u13A7';
      Character x3 = new Character ('\u13A7');
      Character x4 = new Character ('\u13A7');

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      Character x3i = Character.valueOf (x3);
      Character x4i = Character.valueOf (x4);
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nInteger 0:     ");
      Integer x1 = 0;
      Integer x2 = 0;
      Integer x3 = new Integer (0);
      Integer x4 = new Integer (0);

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      Integer x3i = Integer.valueOf (x3);
      Integer x4i = Integer.valueOf (x4);
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nInteger 12:    ");
      Integer x1 = Integer.valueOf(12);
      Integer x2 = Integer.valueOf(12);
      Integer x3 = new Integer (12);
      Integer x4 = new Integer (12);

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      Integer x3i = Integer.valueOf (x3);
      Integer x4i = Integer.valueOf (x4);
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nInteger 13297: ");
      Integer x1 = 13297;
      Integer x2 = 13297;
      Integer x3 = new Integer (13297);
      Integer x4 = new Integer (13297);

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      Integer x3i = Integer.valueOf (x3);
      Integer x4i = Integer.valueOf (x4);
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
    {
      System.out.print ("\nDouble 0.0:    ");
      Double x1 = 0.0;
      Double x2 = 0.0;
      Double x3 = new Double (0);
      Double x4 = new Double (0);

      System.out.format ("%-5b ", x1 == x2);
      System.out.format ("%-5b ", x1 == x3);
      System.out.format ("%-5b ", x3 == x4);

      Double x3i = Double.valueOf (x3);
      Double x4i = Double.valueOf (x4);
      System.out.format ("%-5b ", x1 == x3i);
      System.out.format ("%-5b ", x3i == x4i);
    }
  }
}