From 5d9e50322404146f2b10512cb77fc0b3a4cbbeaa Mon Sep 17 00:00:00 2001
From: p10297854 <944423246@qq.com>
Date: Fri, 9 Jul 2021 18:21:23 +0800
Subject: [PATCH] ADD file via upload

---
 .../com/demo/loginDate/QueryLoginDate.java    | 81 +++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 back/src/com/demo/loginDate/QueryLoginDate.java

diff --git a/back/src/com/demo/loginDate/QueryLoginDate.java b/back/src/com/demo/loginDate/QueryLoginDate.java
new file mode 100644
index 0000000..7561109
--- /dev/null
+++ b/back/src/com/demo/loginDate/QueryLoginDate.java
@@ -0,0 +1,81 @@
+package com.demo.loginDate;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.ArrayList;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletException;
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import com.domain.GetDBConnection;
+import com.domain.Types;
+import com.domain.loginDateInfo;
+
+/**
+ * Servlet implementation class QueryLoginDate
+ */
+@WebServlet("/querylogindate")
+public class QueryLoginDate extends HttpServlet {
+	private static final long serialVersionUID = 1L;
+	loginDateInfo logininfo = new loginDateInfo();
+    /**
+     * @see HttpServlet#HttpServlet()
+     */
+    public QueryLoginDate() {
+        super();
+        // TODO Auto-generated constructor stub
+    }
+
+	/**
+	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
+	 */
+	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+		// TODO Auto-generated method stub
+		 Connection   con = GetDBConnection.connectDB("musicMySQL","root","12345");
+	      Statement sql; 
+	      ResultSet rs;
+	      PreparedStatement preSql;
+		  
+		   String sqlstr="select username,loginDate from loginDateInfo where loginDateID = (select max(loginDateID) from loginDateInfo where username=?)";        		//SQL语句
+		
+				      try { 
+				    	  sql=con.createStatement();
+				        preSql = con.prepareStatement(sqlstr);
+				        String username = request.getParameter("username");
+						username = new String(username.getBytes("iso8859-1"),"UTF-8");
+						 preSql.setString(1, username);
+						 //int ok = preSql.executeUpdate();
+				        rs = preSql.executeQuery();
+				    	rs.next();
+				    	 if(!rs.next()) {
+								response.sendError(204, "insert failed");
+							}else {
+								OutputStream out = response.getOutputStream();
+								//以什么编码打入
+								out.write(rs.getString("username").getBytes());
+								out.write(rs.getString("loginDate").getBytes());
+							}
+							logininfo.setUsername(rs.getString("username"));
+							logininfo.setLoginDate(rs.getString("loginDate"));
+							
+					request.setAttribute("logininfo", logininfo);
+						RequestDispatcher view = request.getRequestDispatcher("/showonelogin.jsp");
+						view.forward(request, response);
+				      } catch(SQLException e) {
+				    	  request.setAttribute("logininfo", logininfo);
+							RequestDispatcher view = request.getRequestDispatcher("/showonelogin.jsp");
+							view.forward(request, response);
+				          
+				      }
+	}
+
+}