《java设计模式》一书的源码

				import java.util.*;
				
				public class productList extends JawtList
				   implements visList
				{
				   public productList() {
				      super(10);     //sets up JawtList  
				   }
				   //-------------------------------------
				   private void splitAdd(String s) {
				      
				      //take each string apart and keep only
				      //the product names, discarding the quntities
				
				      int index = s.indexOf("--");  //separate qty from name
				                  
				      if(index > 0)
				         super.add(s.substring(0, index));
				      else
				         super.add(s);
				   }
				   //-------------------------------------
				   public void addLine(String s) {
				 
				      splitAdd(s);
				      super.validate();
				   }
				   //-------------------------------------
				   public void removeLine(int index) {
				      String s = super.getElementAt(index);
				      super.remove(s);
				   }
				}