设计模式16-迭代子模式

来源：互联网发布：12315投诉有用吗淘宝编辑：程序博客网时间：2024/06/05 16:27

简介

顺序访问聚集中的对象

这里写图片描述

实现

两个接口

public interface Collection {      public Iterator iterator();      /*取得集合元素*/      public Object get(int i);      /*取得集合大小*/      public int size();  }

public interface Iterator {      //前移      public Object previous();      //后移      public Object next();      public boolean hasNext();      //取得第一个元素      public Object first();  }

两个实现：

public class MyCollection implements Collection {      public String string[] = {"A","B","C","D","E"};      @Override      public Iterator iterator() {          return new MyIterator(this);      }      @Override      public Object get(int i) {          return string[i];      }      @Override      public int size() {          return string.length;      }  }

public class MyIterator implements Iterator {      private Collection collection;      private int pos = -1;      public MyIterator(Collection collection){          this.collection = collection;      }      @Override      public Object previous() {          if(pos > 0){              pos--;          }          return collection.get(pos);      }      @Override      public Object next() {          if(pos<collection.size()-1){              pos++;          }          return collection.get(pos);      }      @Override      public boolean hasNext() {          if(pos<collection.size()-1){              return true;          }else{              return false;          }      }      @Override      public Object first() {          pos = 0;          return collection.get(pos);      }  }

测试类：

public class Test {      public static void main(String[] args) {          Collection collection = new MyCollection();          Iterator it = collection.iterator();          while(it.hasNext()){              System.out.println(it.next());          }      }  }

其他设计模式http://blog.csdn.net/qq_23370223/article/category/7193147

阅读全文

0 0