Groovy轻松入门—Grails实战之遗留框架利用-技术开发专区

Groovy轻松入门—Grails实战之遗留框架利用

作者：来自ITPUB论坛编辑： cynthia 2008-01-31 00:00

　　【IT168 技术文档】很多用户(其中也包括我)害怕失去那些自己所熟悉的东西，比如框架，开发环境等。在这篇随笔中，您将看到如何在Grails中利用我们所熟知的框架。其中涉及到配置Spring，配置web.xml和配置dwr.xml，而配置Hibernate在《 Groovy轻松入门——Grails实战之遗留数据库处理篇》中已经讲解过了，所以本篇随笔不再累述。我以利用DWR框架为例稍作讲解。

　　Grails无需任何配置，但不阻止我们配置

　　在Grails0.6+中，配置稍有不同

　　1，“grails create-app dwrDemo”，创建Grails工程

　　2，将dwr.jar(https://dwr.dev.java.net/files/documents/2427/56756/dwr.jar)放到lib目录中(我使用的是DWR2)

　　3，给web-app\WEB-INF\web.template.xml添加如下内容( 我们可以通过修改web.template.xml来达到配置web.xml的目的 )：

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

　　web-app\WEB-INF\web.template.xml的最终内容如下所示：

<? xml version="1.0" encoding="UTF-8" ?>
< web-app  version ="2.4"
xmlns ="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation ="http://java.sun.com/xml/ns/j2ee 
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" >
< context-param >
< param-name > log4jConfigLocation </ param-name >
< param-value > /WEB-INF/classes/log4j.properties </ param-value >
</ context-param >
< context-param >
< param-name > contextConfigLocation </ param-name >
< param-value > /WEB-INF/applicationContext.xml </ param-value >
</ context-param >
< context-param >
< param-name > webAppRootKey </ param-name >
< param-value > dwrtest </ param-value >
</ context-param >
< filter >
< filter-name > sitemesh </ filter-name >
< filter-class > org.codehaus.groovy.grails.web.sitemesh.
GrailsPageFilter </ filter-class >
</ filter >
< filter >
< filter-name > charEncodingFilter </ filter-name >
< filter-class > org.springframework.web.filter.DelegatingFilterProxy
 </ filter-class >
< init-param >
< param-name > targetBeanName </ param-name >
< param-value > characterEncodingFilter </ param-value >
</ init-param >
< init-param >
< param-name > targetFilterLifecycle </ param-name >
< param-value > true </ param-value >
</ init-param >
</ filter >
< filter-mapping >
< filter-name > charEncodingFilter </ filter-name >
< url-pattern > /* </ url-pattern >
</ filter-mapping >
< filter-mapping >
< filter-name > sitemesh </ filter-name >
< url-pattern > /* </ url-pattern >
</ filter-mapping >
< listener >
< listener-class > org.springframework.web.util.
Log4jConfigListener </ listener-class >
</ listener >
< listener >
< listener-class > org.codehaus.groovy.grails.web.context.
GrailsContextLoaderListener </ listener-class >
</ listener >
<!--  Grails dispatcher servlet  -->
< servlet >
< servlet-name > grails </ servlet-name >
< servlet-class > org.codehaus.groovy.grails.web.servlet.
GrailsDispatcherServlet </ servlet-class >
< load-on-startup > 1 </ load-on-startup >
</ servlet >
<!--  The Groovy Server Pages servlet  -->
< servlet >
< servlet-name > gsp </ servlet-name >
< servlet-class > org.codehaus.groovy.grails.web.pages.
GroovyPagesServlet </ servlet-class >
</ servlet >
< servlet-mapping >
< servlet-name > gsp </ servlet-name >
< url-pattern > *.gsp </ url-pattern >
</ servlet-mapping >
<!-- DWR servlet  -->
< 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 >
</ servlet >
< servlet-mapping >
< servlet-name > dwr-invoker </ servlet-name >
< url-pattern > /dwr/* </ url-pattern >
</ servlet-mapping >
< welcome-file-list >
<!--
The order of the welcome pages is important.  JBoss deployment will
break if index.gsp is first in the list.
-->
< welcome-file > index.jsp </ welcome-file >
< welcome-file > index.gsp </ welcome-file >
</ welcome-file-list >
< jsp-config >
< taglib >
< taglib-uri > http://java.sun.com/jsp/jstl/core </ taglib-uri >
< taglib-location > /WEB-INF/tld/c.tld </ taglib-location >
</ taglib >
< taglib >
< taglib-uri > http://java.sun.com/jsp/jstl/fmt </ taglib-uri >
< taglib-location > /WEB-INF/tld/fmt.tld </ taglib-location >
</ taglib >
< taglib >
< taglib-uri > http://www.springframework.org/tags </ taglib-uri >
< taglib-location > /WEB-INF/tld/spring.tld </ taglib-location >
</ taglib >
< taglib >
< taglib-uri > http://grails.codehaus.org/tags </ taglib-uri >
< taglib-location > /WEB-INF/tld/grails.tld </ taglib-location >
</ taglib >
</ jsp-config >
</ web-app >

　　4，在src\java下，建立如下目录结构：

    edu
└─ecust
├─service
│  │  Service.java
│  │
│  └─impl
│          SomeServiceImpl.java
│
└─test
Hello.java

　　Hello.java

　　package edu.ecust.test;
　　import edu.ecust.service.Service;
　　public class Hello {
　　private Service service;
　　public void setService(Service service) {
　　this .service = service;
　　}
　　public String hello(String name) {
　　boolean result = service.doSomething(name);
　　return result ? " Welcome " + name : " Hello " + name;
　　}
　　}
　　Service.java
　　package edu.ecust.service;
　　public interface Service {
　　public boolean doSomething(String name);
　　}
　　SomeServiceImpl.java
　　package edu.ecust.service.impl;
　　import edu.ecust.service.Service;
　　public class SomeServiceImpl implements Service {
　　public boolean doSomething(String name) {
　　if ( " Daniel " .equals(name)) {
　　return true ;
　　} else {
　　return false ;
　　}
　　}
　　}

　　5，修改spring\resources.xml的内容 ( 我们可以通过修改 resources.xml 来达到配置Spring的目的 )：

<? xml version="1.0" encoding="UTF-8" ?>
< beans  xmlns ="http://www.springframework.org/schema/beans"
xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation ="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd" > 

< bean  id ="someService"  class ="edu.ecust.service.impl.SomeServiceImpl"   />
< bean  id ="welcome"  class ="edu.ecust.test.Hello" >
< property  name ="service"  ref ="someService"   />
</ bean >
</ beans >

　　6，在web-app\WEB-INF目录下新建dwr.xml，修改内容如下：

<? xml version="1.0" encoding="UTF-8" ?>
<! DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN" "http://www.getahead.ltd.uk/dwr/dwr20.dtd" >
< dwr >
< allow >
< create  creator ="spring"  javascript ="welcome" >
< param  name ="beanName"  value ="welcome"   />
</ create >
</ allow >
</ dwr >

　　7，在web-app\js目录下新建hello.js，修改内容如下：

　　function hello() {
　　var name = $('name').value;
　　welcome.hello(name, callback);
　　}
　　function callback(msg) {
　　DWRUtil.setValue('result', msg);
　　}

　　8，“grails create-controller User”创建一个UserController

　　9，修改grails-app\controllers\UserController.groovy内容：

　　class UserController {
　　def hello = {}
　　}

　　10，在grails-app\views\user目录下新建新建hello.gsp，修改内容如下：

< html >
< head >
< script  type ='text/javascript'  src ='<%=request.getContextPath()% > / dwr / interface / welcome.js' > </ script >
< script  type ='text/javascript'  src ='<%=request.getContextPath()% > / dwr / engine.js' > </ script >
< script  type ='text/javascript'  src ='<%=request.getContextPath()% > / dwr / util.js' > </ script >
< script  type ='text/javascript'  src ='<%=request.getContextPath()% > / js / hello.js' > </ script >
</ head >
< body >
Name:  < input  id ="name"  type ="text"  onKeyup ='hello();' />
< div  id ="result" ></ div >
</ body >
</ html >

　　11，“grails run-app”，启动这个Web应用程序

　　12，访问http://localhost:8080/dwrDemo/user/hello，并输入Daniel，注意观察效果：

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