`

用velocity代替jsp作为程序视图展示

velocityJSPJavaWebXML 
阅读更多
http://llying.iteye.com/blog/419685
用veloctiy代替jsp作为程序视图展示
这里我们需要一个velocity的扩展工具包veloctiy-tools,我们可以在velocity的官方网站中得到。
在web.xml中配置相关的servlet 
<?xml version="1.0" encoding="UTF-8"?>  
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"  
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee    
    http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">  
    <servlet>  
        <servlet-name>velocity</servlet-name>  
        <servlet-class>  
            org.apache.velocity.tools.view.servlet.VelocityViewServlet   
        </servlet-class>  
        <init-param>  
            <param-name>org.apache.velocity.toolbox</param-name>  
            <param-value>/WEB-INF/toolbox.xml</param-value>  
        </init-param>  
        <init-param>  
            <param-name>org.apache.velocity.properties</param-name>  
            <param-value>/WEB-INF/velocity.properties</param-value>  
        </init-param>  
    </servlet>  
  
    <servlet-mapping>  
        <servlet-name>velocity</servlet-name>  
        <url-pattern>*.vm</url-pattern>  
    </servlet-mapping>  
    <welcome-file-list>  
        <welcome-file>index.jsp</welcome-file>  
    </welcome-file-list>  
</web-app>

toolbox.xml是实体映射文件后面会有说明
velocity.properties是配置文件
这里仅设置了字符编码 
input.encoding=utf-8  
output.encoding=utf-8  
directive.foreach.counter.name = velocityCount
directive.foreach.counter.initial.value = 1
velocimacro.library = /WEB-INF/conf/vm/VM_global_library.vm,/WEB-INF/conf/vm/anyplaceMacro.vm
velocimacro.permissions.allow.inline = true
velocimacro.permissions.allow.inline.to.replace.global = false
velocimacro.permissions.allow.inline.local.scope = false
velocimacro.context.localscope = false

这里我们创建了一个默认的vm模板文件
VM_global_library.vm 放置在/WEB-INF/conf/vm/根目录下 放置一些全局的数据

接下来我们创建一个Person类 
public class Person {   
    private String name;   
    private int id;   
    private int age;   
    public String getName() {   
        return name;   
    }   
    public void setName(String name) {   
        this.name = name;   
    }   
    public int getId() {   
        return id;   
    }   
    public void setId(int id) {   
        this.id = id;   
    }   
    public int getAge() {   
        return age;   
    }   
    public void setAge(int age) {   
        this.age = age;   
    }   
}

PersonService实际处理的对象 
import java.util.ArrayList;   
import java.util.List;   
  
  
public class PersonService {   
    static private List<Person> PERSONS = new ArrayList<Person>();   
    static{   
           
        for (int i = 0 ; i<10;i++){   
            Person p = new Person();   
            p.setId(i);   
            p.setAge(i+3);   
            p.setName("p_name "+i);   
            PERSONS.add(p);   
        }   
    }   
       
    public List<Person> getPersons(){   
        return PERSONS;   
    }   
    public Person getPerson(int id){   
        for(int i = 0 ; i<PERSONS.size() ; i++){   
            Person p = PERSONS.get(i);   
            if(id==p.getId()){   
                return p;   
            }   
        }   
        return null;   
    }   
    public int parseInt(String id){   
        return Integer.parseInt(id);   
    }    
}

现在再看看我们的映射文件应该可以很明确了 
<?xml version="1.0" encoding="UTF-8"?>  
<toolbox>  
  <data type="string">  
     <key>personList</key>  
     <value>用户列表</value>  
  </data>  
  
  <tool>  
     <key>personService</key>  
     <scope>request</scope>  
     <request-path>/person/*</request-path>  
     <class>PersonService</class>  
  </tool>  
</toolbox>

下面看看我们的两个模板
一个是显示全部 一个是显示单个
persons 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">   
<HTML>   
 <HEAD>   
  <TITLE> $personList </TITLE>   
 </HEAD>   
 <BODY>   
  <table>   
    <tr>   
        <td>姓名</td>   
        <td>年龄</td>   
    </tr>   
    #foreach($person in ${personService.getPersons()})   
    <tr>   
        <td><a href="person.vm?id=${person.getId()}">${person.getName()}</a></td>   
        <td>${person.getAge()}</td>   
    <tr>   
    #end   
  </table>   
 </BODY>   
</HTML>

person 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">   
<HTML>   
 <HEAD>   
  <TITLE> $personList </TITLE>   
 </HEAD>   
 <BODY>   
 #set ($paramName = $request.getParameter("id"))   
 $paramName   
  <table>   
    <tr>   
    <td>姓名</td>   
    <td>年龄</td>   
    </tr>   
    #set( $person = ${personService.getPerson($personService.parseInt($paramName))} )   
    <tr>   
        <td>${person.getName()}</td>   
        <td>${person.getAge()}</td>   
    <tr>   
  </table>   
     
 </BODY>   
</HTML>

接下来大家可以看看效果 不过很简陋
有一点令我十分不爽 就是String --> int转换 我自己写得方法
如果有知道更好的希望赐教

分享到：
| Hibernate的批量更新和删除
评论
发表评论

您还没有登录,请您登录后再发表评论

相关推荐

Magicbox
Global site tag (gtag.js) - Google Analytics