Struts2.0.14学习【1】登陆和访问servletAPI

准备工作:[1]在项目中导入jar包

commons-logging-1.0.4.jar

 freemarker-2.3.8.jar

ognl-2.6.11.jar

struts2-core-2.0.14.jar

xwork-2.0.7.jar

以上是struts2.0.14的核心包

mysql-connector-java-5.1.6-bin.jar

最后一个是mysql驱动包

[2]配置web.xml

<filter> <filter-name>struts2</filter-name> <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class> </filter> <filter-mapping> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> 

完成这两步struts2就已经装入项目了

实例： 

数据库连接类：DBHelper.java

package com.accp.Dao; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.sql.Statement; import java.sql.CallableStatement; import java.sql.PreparedStatement; import java.sql.ResultSet; public class DBHelper { private Connection conn; private Statement st; private CallableStatement cst; private PreparedStatement pst; private ResultSet rs; public DBHelper(){ } public Connection getConn(){ try { Class.forName("org.gjt.mm.mysql.Driver").newInstance(); conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/chatroom","root",""); } catch (InstantiationException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalAccessException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return conn; } public int executeUpdate(String sql){ int res=-1; try { st = this.getConn().createStatement(); res = st.executeUpdate(sql); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return res; } public ResultSet executeQuery(String sql){ try { st = this.getConn().createStatement(); rs = st.executeQuery(sql); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return rs; } public static void main(String[] args) { DBHelper dbh= new DBHelper(); ResultSet rs = dbh.executeQuery("select count(*) as c from users"); try { while(rs.next()){ System.out.println(rs.getInt("c")); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void closeAll(){ try { if(rs!=null){ rs.close(); rs = null; } if(pst!=null){ pst.close(); pst=null; } if(cst!=null){ cst.close(); cst=null; } if(st!=null){ st.close(); st=null; } if(conn!=null&&!conn.isClosed()){ conn.close(); conn=null; } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }

登陆处理类LoginDAO.java

package com.accp.Dao; import java.sql.ResultSet; import java.sql.SQLException; public class LoginDao { private DBHelper dbh = new DBHelper(); private String sql=""; public boolean login(String uname,String upass){ //没有做sql注入处理 sql="SELECT COUNT(*) AS p FROM users WHERE uname='"+uname+"' AND upass='"+upass+"'"; ResultSet rs = dbh.executeQuery(sql); int res = -1; try { while(rs!=null&&rs.next()){ res = rs.getInt("p"); } dbh.closeAll(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } if(res==1){ return true; } return false; } }

登陆LoginAction.java

package com.accp.Action; import java.util.ArrayList; import java.util.List; import java.util.Map; import com.accp.Dao.LoginDao; import com.accp.model.User; import com.opensymphony.xwork2.ActionContext; import com.opensymphony.xwork2.ActionSupport; public class LoginAction extends ActionSupport { private String uname; private String upass; Map application; Map session; public String getUname() { return uname; } public void setUname(String uname) { this.uname = uname; } public String getUpass() { return upass; } public void setUpass(String upass) { this.upass = upass; } @Override public String execute() throws Exception { LoginDao ld = new LoginDao(); if(ld.login(uname, upass)){ Object uObj =this.getApplication().get("users"); List users =null; if(uObj==null){ users= new ArrayList(); }else{ users= (ArrayList)uObj; } User u = new User(); u.setUname(uname); users.add(u); this.getApplication().put("users", users); users =(ArrayList)this.getApplication().get("users"); this.getSession().put("myUname", uname); System.out.println("users.Size:"+users.size()); return "success"; } return "fail"; } public Map getApplication(){ ActionContext ctx = ActionContext.getContext(); application = ctx.getApplication(); return application; } public Map getSession(){ ActionContext ctx = ActionContext.getContext(); session = ctx.getSession(); return session; } }

struts.xml配置

<action name="login" class="com.accp.Action.LoginAction"> <result name="success">/index.jsp</result> <result name="fail">/fail.jsp</result> <result name="error">/error.jsp</result> </action>

页面login.jsp

<body> <s:form action="login"> 登陆 <table border="1"> <tr> <td><s:textfield label="用户名：" name="uname"/></td> </tr> <tr> <td><s:textfield label="密码：" name="upass"/></td> </tr> <tr> <td colspan="1"><s:submit value="提交"/></td> </tr> </table> </s:form>

struts2访问servletAPI的关键代码：

ActionContext ctx = ActionContext.getContext(); //获取application对象 application = ctx.getApplication(); //获得session对象 session = ctx.getSession(); //另一种方式获取HttpRequest对象 private String HTTP_REQUEST = org.apache.struts2.StrutsStatics.HTTP_REQUEST; HttpServletRequest request = (HttpServletRequest)ActionContext.getContext().get(HTTP_REQUEST);