Velocity - Snippets

来源：互联网发布：淘宝客服kpi 编辑：程序博客网时间：2024/05/18 21:48

Velocity是一个基于java的模板引擎（template engine）。它允许任何人仅仅简单的使用模板语言（template language）来引用由java代码定义的对象。

Java工程中引入Velocity的包, 这里是velocity-1.4.jar, velocity-dep-1.4.jar.

TestVelocity.java:

package tony.test;

import java.io.StringWriter;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import java.util.Properties;

import org.apache.velocity.VelocityContext;

import org.apache.velocity.app.Velocity;

import org.apache.velocity.app.VelocityEngine;

import org.apache.velocity.context.Context;

import org.apache.velocity.exception.MethodInvocationException;

import org.apache.velocity.exception.ParseErrorException;

import org.apache.velocity.exception.ResourceNotFoundException;

import org.apache.velocity.runtime.RuntimeConstants;

/**

* @author Tony

public class TestVelocity

{

private static VelocityEngine engine = null;

/**

* Initialize velocity

public static void initVelocity() throws Exception

{

engine = new VelocityEngine();

Properties prop = new Properties();

// Set the template file path

prop.setProperty(Velocity.FILE_RESOURCE_LOADER_PATH, "E:/templates");

engine.init(prop);

}

/**

* @param templeteFileName: Velocity templete file name.

* @param values: Velocity templete variables and values map.

* @return Generated content string.

private static String generateContent(String templeteFileName, Map values) throws ResourceNotFoundException, ParseErrorException, MethodInvocationException, Exception

{

Context context = new VelocityContext();

for (Iterator it=values.entrySet().iterator(); it.hasNext();)

{

Map.Entry entry = (Map.Entry)it.next();

context.put((String)entry.getKey(), entry.getValue());

}

StringWriter wr = new StringWriter();

engine.mergeTemplate(templeteFileName, RuntimeConstants.ENCODING_DEFAULT, context, wr);

return wr.toString();

}

public static void main(String[] args) throws Exception

{

initVelocity();

List dothings = new ArrayList();

dothings.add(new DoThings("Haha", "Giggle"));

dothings.add(new DoThings("Hehe", "Smile"));

dothings.add(new DoThings("Kaka", "Die"));

Map values = new HashMap();

values.put("YOUR_CHARACTERISTIC","old");

values.put("YOUR_NAME","Tony");

values.put("DO_THINGS", "laugh");

values.put("REPEAT_TIME", new Integer(dothings.size()));

values.put("ALL_TIMES", dothings);

System.out.println(generateContent("velocity.helloworld.vm", values));

}

DoThings.java:

package tony.test;

/**

* @author Tony

* The class should be public, and implement get/set.

public class DoThings

{

private String name;

private String things;

public DoThings(String name, String things)

{

this.name = name;

this.things = things;

}

public String getName()

{

return name;

}

public void setName(String name)

{

this.name = name;

}

public String getThings()

{

return things;

}

public void setThings(String things)

{

this.things = things;

}

E:/templates/velocity.helloworld.vm(完整路径):

<html>
<body>
I am the $YOUR_CHARACTERISTIC $YOUR_NAME.
 
I will $DO_THINGS for $REPEAT_TIME times:
 
#foreach($EACH_TIME in $ALL_TIMES)
$velocityCount. $EACH_TIME.name -- $EACH_TIME.things
 
#end
 
#if($YOUR_NAME == "Tony")
Best wishes!
#else
Go to die!
#end
</body>
</html>

生成结果:

<html>
<body>
I am the old Tony.
 
I will laugh for 3 times:
 
1. Haha -- Giggle
 
2. Hehe -- Smile
 
3. Kaka -- Die
 
 
Best wishes!
</body>
</html>

一份不错的参考:

Velocity用户手册---中文版(http://www.ijsp.net/2/2003-9/27/0000434.shtml).