springmvc----demo1---hello---bai

import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.support.SessionStatus;
import org.springframework.web.portlet.bind.annotation.RenderMapping;
import org.springframework.web.servlet.ModelAndView;

import com.etc.entity.Book;
import com.etc.entity.Student;

//通过注解创建1个控制器对象
@Controller
public class HelloAction 
{
	public HelloAction() 
	{
		System.out.println("构造了！！！");
	}
	//通过注解配置该方法处理含有hello的请求	
	@RequestMapping("/hello")
	public String hello()
	{
		//返回一个视图标识.自动被映射到/WEB-INF/jsp/hello.jsp的文件
		return "hello"; 
	}
	
	//通过modelandview返回模型和视图的打包
	@RequestMapping("/showdata")
	public ModelAndView showdata()
	{
		Map<String,Object> data = new HashMap<String,Object>();
		data.put("str", " i am bai"); //存储字符串
		data.put("stu", new Student(1,"白")); //存储字符串
		
		ModelAndView ma = new ModelAndView("showdata", data);
		return ma;
	}
	@RequestMapping(method=RequestMethod.GET,value="/showinput")
	public ModelAndView showinput(
	@RequestParam(value="a",required=true) String a,
	@RequestParam(value="b",required=false) String b			
	)
	{
		Map<String,Object> data = new HashMap<String,Object>();
		data.put("a", a); //存储字符串
		data.put("b", b); //存储字符串
		
		ModelAndView ma = new ModelAndView("showinput", data);
		return ma;
	}
	
	//在请求作用域初始化1个空模型
	@ModelAttribute("student")
	public Student initStudent()
	{
		return new Student();
	}
	    
	@ModelAttribute("book")
	public Book initBook()
	{
		return new Book();
	}

	//用于输入一个学生。练习，创建Animal类，aid,aname,feetcount。使用模型驱动输入1个动物并显示。
	@RequestMapping("/input_stu")
	public String showinput_stu
	(@ModelAttribute("student") Student stu
	,@ModelAttribute("book") Book book)				
	{
		return "show_stu";
	}	
	
	@RequestMapping(value="/{a}/{b}/input_path")
	public ModelAndView inputpath(@PathVariable String a,@PathVariable String b)
	{
		Map<String,Object> data = new HashMap<String,Object>();
		data.put("a", a); //存储字符串
		data.put("b", b); //存储字符串
		
		ModelAndView ma = new ModelAndView("showinput_path", data);
		return ma;
	}
	//使用rest风格，录入1个学生
	@RequestMapping(value="/{sid}/{sname}/input_stu_path.html")
	public ModelAndView inputpath(@PathVariable int sid,@PathVariable String sname)
	{
		Map<String,Student> data = new HashMap<String,Student>();
		
		data.put("stu", new Student(sid, sname) ); //存储学生
		
		ModelAndView ma = new ModelAndView("showinput_stu_path", data);
		return ma;
	}
	
	//使用老方法获取request,session
	@RequestMapping(value="/getsession1")
	public String getsession1(HttpServletRequest request)
	{
		request.setAttribute("r", "rrrrrrrrrrr");
		HttpSession s = request.getSession();
		s.setAttribute("s1", "11111111");
		return "show_session1";
	}
	
	
	//使用新方法获取session
	@RequestMapping(value="/getsession2")
	public String getsession1(HttpSession session
			,HttpServletRequest request
			,SessionStatus sta)
	{
		//如果该session被删除，需要重建*/
		if (sta.isComplete())
			session = request.getSession();//重建sessin
		session.setAttribute("s2","222222");
		//session.invalidate(); //删除整个session
		return "show_session2";
	}
}