package top.triabin._02genericinset;
import org.junit.Test;
import java.util.*;
public class GenericTest { @Test public void test1(){ ArrayList list = new ArrayList(); list.add(78); list.add(89); list.add(90); list.add(86);
for(Object score : list){ int stuScore = (Integer)score; System.out.println(stuScore); } }
@Test public void test2(){ ArrayList<Integer> list = new ArrayList<Integer>(); list.add(78); list.add(89); list.add(90); list.add(86);
Iterator<Integer> iterator = list.iterator(); while(iterator.hasNext()){ System.out.println(iterator.next()); } }
@Test public void test3(){
Map<String,Integer> map = new HashMap<>();
map.put("Tom",87); map.put("Jerry",90); map.put("Jack",66);
Set<Map.Entry<String, Integer>> entry = map.entrySet(); Iterator<Map.Entry<String, Integer>> iterator = entry.iterator(); while(iterator.hasNext()){ Map.Entry<String, Integer> e = iterator.next(); String key = e.getKey(); Integer value = e.getValue(); System.out.println(key + "-->" + value); } } }
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