Struts2 + Hibernate3.3 开发简单的登录注册功能【J2EE】

开发环境：

IDE：Myeclipse10.0

数据库：Oracle（SQL Developer）

Web容器：Tomcat 7.0

JDK：1.6

Struts：2.0

Hibernate：3.3

数据库：（ID为主键，设置了序列以及触发器SEQUENCE_ID，使得ID自增）

注意事项：

创建项目以后，为项目添加Sturts和Hibernate能力

连接数据库并生成POJO类：Hibernate框架连接SQL sever 2016完整详细步骤

还有一个一定会出错的地方，因为Hibernate和Struts 2 中有相同的包（版本不同）会引起冲突，所以要把Struts 2 中的antlr-2.7.2.jar移除，具体操作可以看这篇：java.lang.NoSuchMethodError: antlr.collections.AST.getLine()I最终解决方案

编码步骤：

1. 使用hibernate框架生成数据实体POJO类，即该项目中的Userinfo类
2. 编写逻辑层UserDAO类
3. 编写控制层Action类，分为登录Action和注册Action
4. 编写视图层JSP，分为登录界面和注册页面，以及登录、注册成功后通通跳转到成功界面
5. 编写struts.xml，分为两个action，因为有两张form表单要填写以对应跳转不同的视图

POJO类：Userinfo.java

package com.ov;

/**
 * Userinfo entity. @author MyEclipse Persistence Tools
 */

public class Userinfo implements java.io.Serializable {

    // Fields

    private Integer id;
    private String username;
    private String password;
    private String repassword;

    // Constructors

    /** default constructor */
    public Userinfo() {
    }

    /** full constructor */
    public Userinfo(String username, String password, String repassword) {
        this.username = username;
        this.password = password;
        this.repassword = repassword;
    }

    // Property accessors

    public Integer getId() {
        return this.id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return this.username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return this.password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getRepassword() {
        return this.repassword;
    }

    public void setRepassword(String repassword) {
        this.repassword = repassword;
    }

}

自动生成的Userinfo.hbm.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!--
    Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
    <class name="com.ov.Userinfo" table="USERINFO" schema="SYSTEM">
        <id name="id" type="java.lang.Integer">
            <column name="ID" precision="9" scale="0" />
            <generator class="sequence">
            <param name="sequence">SEQUENCE_ID</param>
            </generator>
        </id>
        <property name="username" type="java.lang.String">
            <column name="USERNAME" length="50" />
        </property>
        <property name="password" type="java.lang.String">
            <column name="PASSWORD" length="50" />
        </property>
        <property name="repassword" type="java.lang.String">
            <column name="REPASSWORD" length="50" />
        </property>
    </class>
</hibernate-mapping>

UserDAO.java

package com.dao;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import com.ov.Userinfo;
import com.util.HibernateSessionFactory;

public class UserDAO {
    private Session session;
    private Transaction t;
    //获取session连接
    public  void getCurrentSession() {
        session = HibernateSessionFactory.getSession();
    }
    //关闭session连接
    public void closeSession() {
        if(session != null){
            HibernateSessionFactory.closeSession();
        }
    }

    /**
     * 登录：验证用户名和密码
     * @param user
     * @return true 存在
     * @return false 不存在
     */
    public boolean loginByUser(String username,String password){
            getCurrentSession();
            t = session.beginTransaction();
            Query query = session.createQuery("from Userinfo where username='"+username+"' and password='"+password+"'");
            List list = query.list();
            closeSession();
            if(list!=null && list.size()>0) { //存在用户名和密码
                return true;
            }
            return false;
    }

    /**
     * 注册：先查询表中是否存在相同用户名，若无则增加，有则提示
     * @param userinfo
     * @return true 成功
     * @return false 失败
     */
    public boolean registByUser(Userinfo userinfo) {
        try{
            getCurrentSession();
            t = session.beginTransaction();
            String username = userinfo.getUsername();
            String password = userinfo.getPassword();
            String repassword = userinfo.getRepassword();
            Query query = session.createQuery("from Userinfo where username='"+username+"'");
            //query.setString(0, username);
            List list = query.list();
            if(list.size()>0){     //如果表中已经有相同的用户名
                return false;
            }
            else{
                session.save(userinfo);
                t.commit();
                return true;
            }
        }catch (Exception e) {
            e.printStackTrace();
        }
        finally{
            closeSession();
        }
        return false;
    }
}

LoginAction.java

package com.action;

import java.util.Map;

import org.hibernate.Session;

import com.dao.UserDAO;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.ov.Userinfo;

public class LoginAction extends ActionSupport {
    private String username;
    private String password;
    private String msg;//用于显示错误信息
    /**
     * 处理用户请求的execute方法
     */
    public String execute() throws Exception {
        //获得会话，用来保存当前登录用户的信息！
        Map<String,Object> session = ActionContext.getContext().getSession();
        Userinfo userinfo = new Userinfo();
        userinfo.setUsername(username);
        userinfo.setPassword(password);
        session.put("userinfo", userinfo);
        return SUCCESS;
    }

    public void validate() {
        if(username==null || username.equals("")){
            this.addFieldError("username", "用户名不能为空！");
        }
        else if(password==null || password.equals("")){
            this.addFieldError("password", "密码不能为空！");
        }
        else{
            UserDAO dao = new UserDAO();
            if(dao.loginByUser(username,password) == false){
                this.addFieldError("username", "用户名或密码错误！");
            }
        }
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

}

RegistAction.java

package com.action;

import java.util.Map;

import org.hibernate.Session;

import com.dao.UserDAO;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.ov.Userinfo;

public class LoginAction extends ActionSupport {
    private String username;
    private String password;
    private String msg;//用于显示错误信息
    /**
     * 处理用户请求的execute方法
     */
    public String execute() throws Exception {
        //获得会话，用来保存当前登录用户的信息！
        Map<String,Object> session = ActionContext.getContext().getSession();
        Userinfo userinfo = new Userinfo();
        userinfo.setUsername(username);
        userinfo.setPassword(password);
        session.put("userinfo", userinfo);
        return SUCCESS;
    }

    public void validate() {
        if(username==null || username.equals("")){
            this.addFieldError("username", "用户名不能为空！");
        }
        else if(password==null || password.equals("")){
            this.addFieldError("password", "密码不能为空！");
        }
        else{
            UserDAO dao = new UserDAO();
            if(dao.loginByUser(username,password) == false){
                this.addFieldError("username", "用户名或密码错误！");
            }
        }
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

}

struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
<struts>
    <package name="default" extends="struts-default">
        <!-- 登录 -->
        <action name="loginAction" class="com.action.LoginAction">
            <result name="success">/success.jsp</result>
            <result name="input">/index.jsp</result>
        </action>
        <!-- 注册 -->
        <action name="registAction" class="com.action.RegistAction">
             <result name="success">/success.jsp</result>
                <result name="input">/register.jsp</result>
            </action>
    </package>
</struts>    

index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <title>主页</title>
  </head>

  <body>
    <s:form action="loginAction" method="post">
        <s:fielderror><s:property value="msg"/></s:fielderror>
        <s:textfield label="用户名" name="username"/>
        <s:password label="密码" name="password"/>
        <s:a href="register.jsp">注册</s:a>
        <s:submit value="登录"/>
    </s:form>
  </body>
</html>

register.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    <title>主页</title>
  </head>

  <body>
    <s:form action="registAction" method="post">
    <s:fielderror><s:property value="msg"/></s:fielderror><br>
        <s:textfield label="用户名" name="username"/>
        <s:password label="密码" name="password"/>
        <s:password label="确认密码" name="repassword"/>
        <s:submit value="提交"/> <s:reset value="重置"/>
    </s:form>
  </body>
</html>

success.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    <title>主页</title>
  </head>

  <body>
    <s:set name="userinfo" value="#session['userinfo']"></s:set>
    <s:property value="#userinfo.username"/>，您好！
  </body>
</html>