Java——迭代器遍历容器

迭代器遍历List

package TestIterator_11;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class TestIteratorList {
	public static void main(String[] args) {
		List<String> list = new ArrayList<>();
		list.add("A");
		list.add("B");
		list.add("C");
		list.add("D");
		list.add("E");
		
		for(Iterator<String> iter = list.iterator();iter.hasNext();) {
			String temp = iter.next();
			System.out.println(temp);
		}
	}
}

迭代器遍历Map

package TestIterator_11;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class TestIteratorMap {
	public static void main(String[] args) {
		Map<Integer,String> map = new HashMap<>();
		map.put(10, "A");
		map.put(20, "B");
		map.put(30, "C");
		map.put(40, "D");
		Set<Entry<Integer,String>> ss = map.entrySet();
		for(Iterator<Entry<Integer, String>> iter = ss.iterator();iter.hasNext();) {
			Entry<Integer, String> temp = iter.next();
			System.out.println(temp.getKey()+"----"+temp.getValue());
		}
		
		System.out.println("++++++++++++++++++++");
		
		Set<Integer> keySet = map.keySet();
		for(Iterator<Integer> iter = keySet.iterator();iter.hasNext();) {
			Integer key = iter.next();
			System.out.println(key+"---"+map.get(key));
		}
		
		
	}
}

迭代器遍历Set

package TestIterator_11;

import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

public class TestIteratorSet {
	public static void main(String[] args) {
		Set<String> list = new HashSet<>();
		list.add("A");
		list.add("B");
		list.add("C");
		list.add("D");
		list.add("E");
		
		for(Iterator<String> iter = list.iterator();iter.hasNext();) {
			String temp = iter.next();
			System.out.println(temp);
		}
	}
}