DWR通过Annotation与spring整合

DWR 2.0 增加了一个很有趣的新特性，Annotation，因此可以摆脱了dwr.xml里面的配置.同时也可以方便的和spring整合.

  从官方网站下载dwr.jar包。然后将它放在你webapp的WEB-INF/lib目录下。 修改web.xml

 

< servlet >
         < servlet-name > dwr-invoker </ servlet-name >
         < servlet-class >
            org.directwebremoting.servlet.DwrServlet
         </ servlet-class >
         < init-param >
             < param-name > debug </ param-name >
             < param-value > true </ param-value >
         </ init-param >
         < init-param >
             < param-name > logLevel </ param-name >
             < param-value > DEBUG </ param-value >
         </ init-param >
         < init-param >
             < param-name > classes </ param-name >
             < param-value >
       com.spring.User,com.beans.Book
             </ param-value >
         </ init-param >
     </ servlet >

     < servlet-mapping >
         < servlet-name > dwr-invoker </ servlet-name >
         < url-pattern > /dwr/* </ url-pattern >
     </ servlet-mapping >

     < context-param >
         < param-name > contextConfigLocation </ param-name >
         < param-value >
            /WEB-INF/beans.xml
         </ param-value >
     </ context-param >
     < listener >
         < listener-class >
            org.springframework.web.context.ContextLoaderListener
         </ listener-class >
     </ listener >

 

       beans.xml是spring的配置文件.org.springframework.web.context.ContextLoaderListener是一个监听器.

<  init-param  >  
              <  param-name  >  classes  </  param-name  >  
              <  param-value  >  
       com.spring.User,com.beans.Book
              </  param-value  >  
          </  init-param  >  

param-value:参数为被注解的类. 

编写相关类          
  com.beans.Book:

@DataTransferObject(converter=BeanConverter.class)
public   class  Book {
    @RemoteProperty
     private  String name;
    @RemoteProperty
     private  String author;

     public  String getAuthor() {
         return  author;
    }

     public   void  setAuthor(String author) {
         this .author  =  author;
    }

     public  String getName() {
         return  name;
    }

     public   void  setName(String name) {
         this .name  =  name;
    }
}

        @DataTransferObject: 标注在客户端和服务器之间转换类.对应dwr.xml中的<convert>标签.
               注解的源代码:
                     

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
public  @ interface  DataTransferObject
{
     /**
     * Converter that converts instance of the class (default: bean converter).
      */
    Class <?   extends  Converter >  converter()  default  BeanConverter. class ;

     /**
     * Parameters for the converter.
      */
    Param[] params()  default  {};
}

         关于annotation可以看这篇文章,java元数据
        @RemoteProperty :标注在类中需要转换的属性.
            源代码:
                  

@Target({ ElementType.FIELD, ElementType.METHOD })
@Retention(RetentionPolicy.RUNTIME)
public  @ interface  RemoteProperty
{
}

       如果使用dwr.xml配置,可以这样:
      

< convert  converter ="bean"  match ="com.beans.Book" >
   < param  name ="include"  value ="name, author" />
</ convert >

 User:

@RemoteProxy(name = " user " ,creator = SpringCreator. class ,
        creatorParams = {
            @Param(name = " beanName " ,value = " user " )
            })
@DataTransferObject(converter = BeanConverter. class )
public   class  User {
    @RemoteProperty 
     private  String welcome;
    @RemoteProperty 
     private  String username;
    @RemoteProperty 
     private  String address;
    @RemoteProperty 
     private  List < Book >  books;
    @RemoteProperty
     private   int  age;

     public  String getAddress() {
         return  address;
    }

     public   void  setAddress(String address) {
         this .address  =  address;
    }

     public   int  getAge() {
         return  age;
    }

     public   void  setAge( int  age) {
         this .age  =  age;
    }
    @RemoteMethod
     public  String getUsername() {
         return  username;
    }

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

     public  String getWelcome() {
         return  welcome;
    }

     public   void  setWelcome(String welcome) {
         this .welcome  =  welcome;
    }
    @RemoteMethod
     public  List < Book >  getBooks() {
         return  books;
    }
    
     public   void  setBooks(List < Book >  books) {
         this .books  =  books;
    }
    @RemoteMethod
     public  User getUser(String welcome) {
         this .welcome  =  welcome;
         return   this ;
    }

}

      @RemoteProxy:标注要给远程调用的类.
               RemoteProxy的name设置创造出来的对象的名字,creator指定使用那种创造器,例子中使用SpringCreator.creatorParams指定创造器的其他参数.不同的创造器参数是不同的.
      @RemoteMethod:标注给远程调用的方法

4.修改beans.xml
      

< bean  id ="remote"  class ="com.spring.Remote" ></ bean >
     < bean  id ="user"  class ="com.spring.User"  
            p:username ="windfree"  p:address ="anhui hefei"  p:age ="25" >
         < property  name ="books" >
             < list >
                 < ref  bean ="C" />
                 < ref  bean ="java" />
             </ list >
         </ property >
     </ bean >
     < bean  id ="java"  class ="com.beans.Book"  p:name ="java"  p:author ="mypure" ></ bean >
     < bean  id ="C"  class ="com.beans.Book"  p:name ="C"  p:author ="zgliu" ></ bean >

   其中p为spring2.0中提供的标签.
5.html页面
      

<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" >
< html >
     < head >
         < title > SpringUserInfo.html </ title >
         < script  type ='text/javascript'  src ='/DWRExample/dwr/interface/user.js' ></ script >
         < script  type ='text/javascript'  src ='/DWRExample/dwr/engine.js' ></ script >
         < script  type ='text/javascript'  src ='/DWRExample/dwr/util.js' ></ script >
         < script  type ="text/javascript" >
         function  test(){
            user.getUser( " Hello " ,callback);   
        }
         var  cellFuncs  =  [
               function (data) {  return  data.name; },
               function (data) {  return  data.author; },
            ];
         function  callback(user){
             // alert(user.books)
             DWRUtil.setValue('result', " 欢迎你！ " + "    姓名： " + user.username + " ,年龄： " + user.age + " ，住址： " + user.address);   
             DWRUtil.addRows('tableInfo',user.books,cellFuncs,
                     { escapeHtml: false  ,
                   rowCreator: function (options) {
                         var  row  =  document.createElement( " tr " );
                         var  index  =  options.rowIndex  *   50 ;
                        row.style.color  =   " rgb( "   +  index  +   " ,0,0) " ;
                         return  row;
                      },
                  cellCreator: function (options) {
                     var  td  =  document.createElement( " td " );
                     var  index  =   255   -  (options.rowIndex  *   50 );
                    td.style.backgroundColor  =   " rgb( "   +  index  +   " ,255,255) " ;
                    td.style.fontWeight  =   " bold " ;
                     return  td;
                  }
             })
        }
     </ script >


     </ head >

     < body >
         &nbsp;&nbsp;&nbsp;   &nbsp;&nbsp;
         < input  id ="jbutton"  type ="button"  value ="取得信息"  onclick ="test()"   />
         < br >
         < div  id ="result" ></ div >< br >
         < table  border ="1" >
             < thead >< tr >
                 < th > 书名 </ th >< th > 姓名 </ th >                 
             </ tr ></ thead >
             < tbody  id ="tableInfo" >
             </ tbody >
         </ table >
     </ body >
</ html >

      其中使用了util.js中的一些函数.