无序单列集合Set:HashSet\TreeSet
无序双列集合Map:HashMap\TreeMap

import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map.Entry;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;

public class de {
	public static void main(String[] args) {
		HashSet<Integer> set = new HashSet<Integer>();
		set.add(4);set.add(6);set.add(5);
		System.out.println("HashSet遍历");
		for(Integer item:set)
		{
			System.out.print(item+"  ");
		}
		System.out.println();
		
		System.out.println("TreeSet遍历");
		TreeSet<Integer> tree = new TreeSet<Integer>();
		tree.add(1);tree.add(19);tree.add(10);tree.add(9);
		for(Integer item:tree)
		{
			System.out.print(item+"  ");
		}
		System.out.println();
		
		System.out.println("HashMap遍历");
		HashMap<Integer,String> map1 = new HashMap<Integer,String>();
		map1.put(1, "小猪");map1.put(2, "小牛");map1.put(0, "小明");
		//遍历数据对元素
		Set<Entry<Integer,String>> set1 = map1.entrySet();
		for(Entry<Integer,String> item:set1)
		{
			System.out.print(item+"  ");
		}
		System.out.println();
		
		//遍历key
		System.out.println("HashMap的KeySet遍历");
		Set<Integer> set11 = map1.keySet();
		for(Integer item:set11)
		{
			System.out.print(item+"  ");
		}
		System.out.println();
		
		//遍历value
		System.out.println("HashMap的values遍历");
		Collection<String> col12 = map1.values();
		for(String item:col12)
		{
			System.out.print(item+"  ");
		}
		System.out.println();
		
		System.out.println("TreeMap遍历");
		TreeMap<Integer,String> map2 = new TreeMap<Integer,String>();
		map2.put(1, "小猪");map2.put(2, "小牛");map2.put(0, "小明");
		//遍历数据对元素
		Set<Entry<Integer,String>> set2 = map2.entrySet();
		for(Entry<Integer,String> item:set2)
		{
			System.out.print(item+"  ");
		}
		System.out.println();
		
		//遍历key
		System.out.println("TreeMapd的KeySet遍历");
		Set<Integer> set21 = map2.keySet();
		for(Integer item:set21)
		{
			System.out.print(item+"  ");
		}
		System.out.println();
		
		//遍历value
		System.out.println("TreeMap的values遍历");
		Collection<String> col22 = map2.values();
		for(String item:col22)
		{
			System.out.print(item+"  ");
		}
	}
}