servlet连接MySQL

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1.get 向服务器请求，索取数据 post 向服务器发送数据。

2、 request.toString();//结果：org.apache.catalina.connector.RequestFacade@171fa02

request.getParameter("account");//结果：zheee

<输出

PrintWriter pw = response.getWriter();pw.println("1:"+rq+"\n");pw.print("2:"+pw);

3.JDBC访问数据库

（1）加载驱动程序。Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

（2）打开数据库连接。url为数据库

Connection connector = null;

connector = (Connection) DriverManager.getConnection(url,"root","ahayouzi");

（3）获得statement对象。

（4）执行SQL语句，通过statement提出

（5）处理结果集。

DBUtil.java

import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;//import java.sql.Statement;import java.sql.Statement;import com.mysql.jdbc.Connection;public class DBUtil { // table      public static final String TABLE_PASSWORD = "table_user_password";      public static final String TABLE_USERINFO = "table_user_info";          static ResultSet rs;    // connect to MySql database      public static Statement getStatementt() {          String url = "jdbc:mysql://localhost:3306/first_mysql_test"; // 数据库的Url          Connection connecter = null;          Statement stm = null;        try {              Class.forName("com.mysql.jdbc.Driver"); // java反射，固定写法  加载驱动            connecter = (Connection) DriverManager.getConnection(url, "root", "ahayouzi");             stm = connecter.createStatement();        } catch (ClassNotFoundException e) {              e.printStackTrace();          } catch (SQLException e) {      }return stm;      }}

secondServlet.java(创建servlet)

public class secondServlet extends HttpServlet {private static final long serialVersionUID = 1L;           /**     * @see HttpServlet#HttpServlet()     */    public secondServlet() {        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//response.getWriter().append("Served at: ").append(request.getContextPath());Statement stmt = null;String sqlQuery;String sqlInsert;int row1;ResultSet result;response.setCharacterEncoding("utf-8");response.setContentType("text/html;charset=utf-8");String rq = request.getParameter("account");PrintWriter pw = response.getWriter();pw.println("1:"+rq+"\n");pw.print("2:"+pw);//pw.flush();try {stmt = DBUtil.getStatementt();sqlQuery = "SELECT * FROM "+DBUtil.TABLE_PASSWORD;result = stmt.executeQuery(sqlQuery);if(result.next()){pw.println("success!!!");sqlInsert = "INSERT INTO "+DBUtil.TABLE_PASSWORD+" values('3','azhen','3') ";row1 = stmt.executeUpdate(sqlInsert);if(row1 == 1){pw.print("insert success~");}else{pw.println("insert failed~");}}else{pw.println("NOPE!");}} catch (SQLException e) {}}/** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubdoGet(request, response);}}

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