1 /**
   2  * TemplateMethodPattern Example
   3  */
   4 
   5 abstract class AbstractDisplay {
   6     public abstract void open();
   7     public abstract void print();
   8     public abstract void close();
   9     public final void display() {
  10         open();
  11         for(int i=0; i<5; i++) print();
  12         close();
  13     }
  14 }
  15 
  16 class CharDisplay extends AbstractDisplay {
  17     private char ch;
  18     public CharDisplay(char ch) {
  19         this.ch = ch;
  20     }
  21     public void open() {
  22         System.out.print("<<");
  23     }
  24     public void print() {
  25         System.out.print(ch);
  26     }
  27     public void close() {
  28         System.out.println(">>");
  29     }
  30 }
  31 
  32 class StringDisplay extends AbstractDisplay {
  33     private String string;
  34     private int width;
  35     public StringDisplay(String string) {
  36         this.string = string;
  37         this.width = string.getBytes().length;
  38     }
  39     public void open() {
  40         printLine();
  41     }
  42     public void print() {
  43         System.out.println("|"+string+"|");
  44     }
  45     public void close() {
  46         printLine();
  47     }
  48     private void printLine() {
  49         System.out.print("+");
  50         for(int i=0; i<width; i++) {
  51             System.out.print("-");
  52         }
  53         System.out.println("+");
  54     }
  55 }
  56 
  57 public class TemplateMethodDisplay {
  58     public static void main(String[] args) {
  59         AbstractDisplay d1 = new CharDisplay('H');
  60         AbstractDisplay d2 = new StringDisplay("Hello world");
  61         d1.display();
  62         d2.display();
  63     }
  64 }