Servlet简单例子：输出当前日期

# JJU_干干

方法：

用到两个时间包：

import java.time.LocalDate;

import java.time.format.DateTimeFormatter;

调用LocalDate类的now方法获取当前时间：
```
LocalDate.now()
```
调用DataTimeFormatter定义日期格式：
```
DateTimeFormatter.ofPattern("yyyy-MM-dd")
```
调用LocalData.now()的format()输出时间：
```
LocalDate.now().format()
```

代码：

package case_01;

import java.io.IOException;
import java.io.PrintWriter;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class TimeNow
 */
@WebServlet("/TimeNow")
public class TimeNow extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public TimeNow() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        // 以下两条语句防止输入中文出现乱码
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset = utf-8");
        response.getWriter().append("Served at: ").append(request.getContextPath());
        PrintWriter out = response.getWriter();
        
        // 获取当前日期
        LocalDate date = LocalDate.now();
        // 定义日期格式： yyy-MM-dd：年-月-日
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd"); 
        //输出当前日期
        out.print(" 今天是："+date.format(formatter));
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

}

运行结果：