链接数据库的两种方式:
1.在Action中连接数据库
2.使用工具类连接数据库
1.在Action中连接数据库
源码文档目录如图所示:
1.建立数据库
数据库建立语句:
create database aynu;
use aynu;
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for `person`
-- ----------------------------
DROP TABLE IF EXISTS `person`;
CREATE TABLE `person` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
`gender` varchar(255) DEFAULT NULL,
`age` int(11) DEFAULT NULL,
`city` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8; -- ----------------------------
-- Records of person
-- ----------------------------
2.加载struts2核心jar包和数据库驱动包
struts2核心jar包,加载方法略。
xwork-core-2.1.6.jar: Structs2框架的核心类库
struts2-core-2.1.8.1.jar: XWork类库,Structs2在其上构建
ognl-2.7.3.jar:对象图导航语言(Object Graph Navigation Language),Structs2框架通过其读写对象属性。
freemarker-2.3.15.jar: Structs2的UI标签的模板使用FreeMarker编写
commons-logging-1.0.4.jar: ASF出品的日志包,Structs2框架使用这个日志包来支持Log4J和JDK1.4+的日志记录。
commons-fileupload-1.2.1.jar: 文件上传组件,2.1.6版本后必须加入此文件。
数据库驱动包:
mysql-connector-java-3.1.12-bin.jar
3.index.jsp源码如下:
<%@ page pageEncoding="utf-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>register page</title>
</head>
<body>
<form action="register.action" method="post">
姓名:<input type="text" name="name"/><br/>
性别:<input type="radio" name="gender" value="male" checked="checked"/>男
<input type="radio" name="gender" value="female"/>女<br/>
年龄:<input type="text" name="age"/><br/>
城市:<input type="text" name="city"/><br/>
<input type="submit" value="注册"/>
</form>
</body>
</html>
4.show.jsp源码如下:
<%@ page pageEncoding="utf-8"%>
<html>
<head>
<title>show page</title>
</head>
<body>
插入完成!
</body>
</html>
5.RegisterAction.java源码如下:
package cn.edu.aynu.Stu_con_DataSql.actions; import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException; public class RegisterAction {
private String name;
private String gender;
private int age;
private String city;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
} public String execute(){
//将数据插入到数据库 //1.加载数据库驱动
try {
String driverName="com.mysql.jdbc.Driver";
Class.forName(driverName);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
Connection con=null;
PreparedStatement ps=null;
try { //2.数据库链接
String url="jdbc:mysql://127.0.0.1:3306/aynu";
String user="root";
String password="toor";
con=DriverManager.getConnection(url,user,password);//这里选择import java.sql.Connection; //插入SQL语句
String sql="insert into person(name,gender,age,city)values(?,?,?,?)";
ps=con.prepareStatement(sql); //插入数据
ps.setString(1, name);
ps.setString(2, gender);
ps.setInt(3, age);
ps.setString(4,city);
//执行SQL语句插入命令
ps.executeUpdate(); } catch (SQLException e) {
e.printStackTrace();
}finally{
try {
ps.close();
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return "success";
}
}
6.web.xml配置如下:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter> <filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping> <welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
7.struts.xml配置如下:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd"> <struts> <package name="one" extends="struts-default"> <action name="register" class="cn.edu.aynu.Stu_con_DataSql.actions.RegisterAction">
<result>/show.jsp</result>
</action> </package> </struts>
8.部署发布,启动tomcat,地址输入:
http://127.0.0.1:8080/Stu_con_DataSql/
程序截图如下:
数据插入数据库成功!
2.使用工具类连接数据库
只需要修改上面的RegisterAction.java和新增加一个工具类JdbcUtil.java即可。
RegisterAction.java源码如下:
package cn.edu.aynu.Stu_con_DataSql.actions; import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException; import cn.edu.aynu.Stu_con_DataSql.utils.JdbcUtil; public class RegisterAction {
private String name;
private String gender;
private int age;
private String city;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
} public String execute(){
//将数据插入到数据库 //1.加载数据库驱动
Connection con=JdbcUtil.getConnection();
PreparedStatement ps=null;
try { //插入SQL语句
String sql="insert into person(name,gender,age,city)values(?,?,?,?)";
ps=con.prepareStatement(sql); //插入数据
ps.setString(1, name);
ps.setString(2, gender);
ps.setInt(3, age);
ps.setString(4,city);
//执行SQL语句插入命令
ps.executeUpdate(); } catch (SQLException e) {
e.printStackTrace();
}finally{
try {
ps.close();
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return "success";
}
}
JdbcUtil.java源码如下:
package cn.edu.aynu.Stu_con_DataSql.utils; import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement; //数据库工具类
public class JdbcUtil { //这里引用import java.sql.Connection;
private static Connection con; //1.加载数据库驱动
static{ try {
String driverName="com.mysql.jdbc.Driver";
Class.forName(driverName);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} } //2.数据库链接
public static Connection getConnection(){ String url="jdbc:mysql://127.0.0.1:3306/aynu";
String user="root";
String password="toor";
try {
con=DriverManager.getConnection(url,user,password);
} catch (SQLException e) {
e.printStackTrace();
}
return con;
} //3.数据库全部关闭
public static void close(Connection con,Statement stmt,ResultSet rs){
//引入java.sql.Satement包,import java.sql.ResultSet,import java.sql.Connection;
try {
if(con!=null)con.close();
if(stmt!=null)stmt.close();
if(rs!=null)rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
//4.数据库选择关闭
public static void close(Object obj){
try {
if(obj instanceof Connection &&obj!=null)((Connection)obj).close();
if(obj instanceof Statement &&obj!=null)((Statement)obj).close();
if(obj instanceof ResultSet &&obj!=null)((ResultSet)obj).close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
重新部署发布,启动tomcat,输入地址:
http://127.0.0.1:8080/Stu_con_DataSql/