java 14 enhanced for loop

com.java14.myjava package;

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

import org.junit.Test;

public class TestArrays {
@Test
public void test1()
{

List<String> list=new ArrayList<String>();
list.add("TOM");
list.add("TOM2");
list.add("TOM3");

Iterator<String> it=list.iterator();
while(it.hasNext())
{
System.out.println(it.next());
}


int[] arr={3,1,2,5};
for (int i=0;i<arr.length;i++)
{
System.out.println(arr[i]);
}

//增强for循环
for(int i : arr)
{
System.out.println(i);
}


Map<String,String> map=new HashMap<String,String>();
map.put("1","Alice");
map.put("2","Alice2");
map.put("3","Alice3");
//迭代entry集合

/*
for( Entry<String,String> e:set)
{
String key = e.getKey();
String value=e.getValue();

System.out.println(key+value);
}
*/

Set<String> set =map.keySet();
for(String s :set)
{
System.out.println(s+"="+map.get(s));
}


}

/**
* 测试变长参数
*/
@Test
public void testVarParam(){
List<String> list=new ArrayList<String>();
addEle(list,"TOM","tompkj","cdnoe","xdweopo");
System.out.println(list.size());
}

private void addEle(List<String> list,String a, String...x)
{
for(String s:x)
{
list.add(s);
}
}

}

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Origin www.cnblogs.com/simly/p/11040005.html