泛型_变量

package javatest;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.junit.Test;
import java.util.Map;
public class PersonTest {
@Test public void xxx() throws Exception
{
	List names = new ArrayList();
	names.add("xxx");
	names.add(90);
	String name = (String)names.get(0);
	Integer age = (Integer)names.get(1);
	System.out.println(name+""+age);
	
}

@Test public void xxx2() throws Exception
{
	List <String>names = new ArrayList<String>();
	names.add("zhangsan");
	names.add("12");
String name = names.get(0);
String age = names.get(1);
	System.out.println(name+""+age);
	
}

@Test public void xxx3() throws Exception
{
	Map <String,Integer> maps = new HashMap<String,Integer>();
   maps.put("第一", 34);
   maps.put("第二", 399);
	for(String key :maps.keySet())
	{
		System.out.println(key+"="+maps.get(key));
	}
	
	
	for(Map.Entry<String, Integer> entry : maps.entrySet())
	{
		
		System.out.println(entry.getKey()+"="+entry.getValue());
	}
}





}