Map集合的常見遍歷
entryset(迭代器foreach)
keyset(迭代器foreach)
values(只能拿到值)
package com.zjx.map;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
public class TestMap2 {
public static void main(String[] args) {
Map map = new HashMap<>();
map.put("鄧超","孫儷");
map.put("張無忌","趙敏");
map.put("張繼科","景甜");
System.out.println("keySet之iterator");
Set keySet = map.keySet();
Iterator iterator = keySet.iterator();
while(iterator.hasNext()){
Object key = iterator.next();
System.out.println(key + "--->"+map.get(key));
}
System.out.println("keySet之foreach");
for (Object key : keySet) {
System.out.println(key + "--->"+map.get(key));
}
System.out.println("--------------------------------");
System.out.println("entrySet之iterator");
Set entrySet = map.entrySet();
Iterator iterator2 = entrySet.iterator();
while (iterator2.hasNext()) {
Map.Entry obj = (Map.Entry)iterator2.next();
System.out.println(obj.getKey()+ "--->"+obj.getValue());
}
System.out.println("entrySet之foreach");
for (Object temp : entrySet) {
Map.Entry obj = (Map.Entry)temp;
System.out.println(obj.getKey()+ "--->"+obj.getValue());
}
System.out.println("--------------------------------");
Collection values = map.values();
for (Object value : values) {
System.out.println("值:"+value);
}
}
}