DWR 配置与参数

DWR 配置与参数

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>activeReverseAjaxEnabled</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>initApplicationScopeCreatorsAtStartup</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>maxWaitAfterWrite</param-name>
<param-value>500</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>

多dwr.xml文件的配置

可能有几种情况，我们一一列举。 一个servlet,多个dwr.xml配置文件；多个servlet，每个servlet对应一个或多个dwr.xml.

一个Servlet 多个dwr.xml配置文件：

<servlet>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>uk.ltd.getahead.dwr.DWRServlet</servlet-class>
<init-param>
<param-name>config-1</param-name>
<param-value>WEB-INF/dwr1.xml</param-value>
</init-param>
<init-param>
<param-name>config-2</param-name>
<param-value>WEB-INF/dwr2.xml</param-value>
</init-param>
</servlet>

在这种配置下，param-name的值必须以config开头。param-name可以有>=0个。如果没有param-name，那么将会读取WEB-INF/dwr.xml。如果有大于零个param-name，那么WEB-INF/dwr.xml文件将不会被读取。

多个servlet，每个servlet对应一个或多个dwr.xml ：

<servlet>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>uk.ltd.getahead.dwr.DWRServlet</servlet-class>
</servlet>

<servlet>
<servlet-name>dwr-invoker1</servlet-name>
<servlet-class>uk.ltd.getahead.dwr.DWRServlet</servlet-class>
<init-param>
<param-name>config-admin</param-name>
<param-value>WEB-INF/dwr1.xml</param-value>
</init-param>
<init-param>
<param-name>debug</param-name>
<param-value>true</param-value>
</init-param>
</servlet>

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

<servlet-mapping>
<servlet-name>dwr-invoker1</servlet-name>
<url-pattern>/dwr1/*</url-pattern>
</servlet-mapping>

在这种情况下，我们可以根据J2EE security来控制权限，针对不同url,加不同的角色。

页面引用

<script type='text/javascript' src='<%=path %>/dwr/interface/loginService.js'></script>
<script type='text/javascript' src='<%=path %>/dwr/engine.js'></script>
<script type='text/javascript' src='<%=path %>/dwr/util.js'></script>

loginService 是dwr.xml中定义的 javaScript名称

测试路径:
http://localhost:8080/项目名称/dwr
dwr.xml是DWR的配置文件。默认情况下，应该把它放到WEB-INF目录下

new: 用Java的new关键字创造对象。

static: 使用“getInstance()的方法(默认情况下)来获得类的一个实例.

none: 它不创建对象，看下面的原因。 (v1.1+)

scripted: 通过BSF使用脚本语言创建对象，例如BeanShell或Groovy。

spring: 通过Spring框架访问Bean。

jsf: 使用JSF的Bean。 (v1.1+)

struts: 使用Struts的FormBean。 (v1.1+)

pageflow: 访问Beehive或Weblogic的PageFlow。 (v1.1+)

常用的3种Creator:

Creator	Param	User
new	class	类的全名称(包括包路径)
scripted	language	BSF框架支持的脚本语言名称(BSF为apache项目)
	script	返回远程对象的脚本,脚本可以指定一些属性,多数情况下一般只设置param节点配置.属性很少设置.
spring	Location*	任何以location开头的参数,每个参数都是指定一个spring的配置文件,在参数没有设置的情况下DWR会去读取spring的全局的配置文件.
	beanName	从配置文件中读取的bean的名称

new:

<allow>
<create creator="new" javascript="Blah">
<param name="class" value="java.util.Date"/>
</create>
...
</allow>

static: 看官网文档 http://directwebremoting.org/dwr/documentation/server/configuration/dwrxml/creators/index.html#none
none:看官网文档 http://directwebremoting.org/dwr/documentation/server/configuration/dwrxml/creators/index.html#none
scripted：

<allow>
...
<create creator="script" javascript="EmailValidator">
<param name="class" value="org.apache.commons.validator.EmailValidator"/>
<param name="language" value="beanshell"/>
<param name="script">
import org.apache.commons.validator.EmailValidator;
return EmailValidator.getInstance();
</param>
</create>
...
</allow>

Parameter	DWR Version	Description
language	1.0	The language that we are scripting in. This string is passed to BSF. For example 'beanshell'. (required)
class	1.0	The type of object that is created. This is required for security reasons.
script	1.0	The script to execute which will return a Java Object to remote. (required unless scriptPath is used)
scriptPath	1.1	The path to a script stored in a file. (required unless script is used)
reloadable	1.1	Should the ScriptedCreator check for changes to scripts loaded using scriptPath? (optional, defaults to true)

spring：

<allow>
...
<create creator="spring" javascript="Fred">
<param name="beanName" value="Shiela"/>
</create>
...
</allow>

使用location*参数

如果你要在dwr.xml中指定使用哪些bean，你可以使用location*参数。你可以指定任意多个文件，只要参数以location开始 并且唯一即可。例如：location-1, location-2。这些location被用做Spring的ClassPathXmlApplicationContext的参数：

<allow>

<create creator="spring" javascript="Fred">

<param name="beanName" value="Shiela"/>

<param name="location" value="beans.xml"/>

</create>

</allow>

直接设置BeanFactory

SpringCreator有一个静态方法 setOverrideBeanFactory(BeanFactory) 用来通过编程的方式直接设置BeanFactory。

JSF:看官网文档 http://directwebremoting.org/dwr/documentation/server/configuration/dwrxml/creators/index.html#none
Struts:看官网文档 http://directwebremoting.org/dwr/documentation/server/configuration/dwrxml/creators/index.html#none
pageflow:看官网文档 http://directwebremoting.org/dwr/documentation/server/configuration/dwrxml/creators/index.html#none

Converters:

http://directwebremoting.org/dwr/documentation/server/configuration/dwrxml/converters/index.html