DWR案例

DWR案例
2010-11-11  author: heguikun

1.web.xml 中添加如下代碼；

  <!-- dwr start -->
<servlet>
  <servlet-name>dwr</servlet-name>
  <servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
  <init-param>
   <param-name>debug</param-name>
   <param-value>true</param-value>
  </init-param>
</servlet>
<servlet-mapping>
<servlet-name>dwr</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>
  <!-- dwr end -->

2.頁面腳步

<script src="dwr/interface/EmployeeObj.js"></script><!-- 自定義的類，腳步的對象-->
 <script src="dwr/engine.js"></script>
 <script src="util.js"></script>
<script type="text/javascript">
function employertExists(oCtl)
 {
  var employertName=oCtl.value;
  if(!employertName)
  {
  alert("員工名不能爲空！");
  oCtl.focus();
  return;
  }
    EmployeeObj.check(employertName,employertDWR);//這腳本的聲明在dwr.xml
 }
 function  employertDWR(isExist)
 {//已經存在返回true 不存在返回false
      alert(isExist);
       if(isExist==0)//返回值是真假，用0代表不存在= false
        { 
        alert("該寵物名可用！");
        }else
        {//1代表ture
         alert("該寵物名已被使用或者其他原因導致這個名字不能用！");
        }
 
 }

</script>

3.要轉換成腳本的類

package com.aptech.jb.epet.biz;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

import com.aptech.jb.epet.entity.HibernateSessionFactory;

public class EmployeeManager extends HibernateDaoSupport{
 // dwr 可以將類發佈爲腳本調用的對象
 public boolean check(String empName) {
  boolean isExist=false;
  //有Hibernate配置文件才能使用HibernateSessionFactory
  Session session = HibernateSessionFactory.getSession();
  Query query = session.createQuery("from  Employer where empName='"
    + empName + "'");
  List list = query.list();
  System.out.println("檢查的員工名爲："+empName+"長度；"+list.size());
  if (list != null && list.size() > 0) {
   session.close();
   isExist=true;
  }
  return isExist;//返回值讓腳本接受
 }
 public static void main(String[] args) {
  EmployeeManager employeeManager=new EmployeeManager();
  employeeManager.check("wo");
 }
}

4.導入dwr.jar到項目的lib下

5.完成以上幾步可以運行了，祝你成功！