《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);
				    }
				}