初始velocity

Velocity是一个基于java的模板引擎。它允许任何人仅仅简单的使用模板语言来引用由java代码

定义的对象。

工程目录为：





example.vm内容如下：

#set( $this = "Velocity")

$this is great!

#foreach( $name in $list )
    $name is great!
#end

#set( $condition = true)

#if ($condition)
    The condition is true!
#else
    The condition is false!
#end

Example.java代码如下：

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.    
 */

package com.test;

import java.io.BufferedWriter;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Properties;

import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;

public class Example
{
    public Example(String templateFile)
    {
        try
        {
            Properties p = new Properties() ;
            String basePath = "src/template";
            p.setProperty(Velocity.FILE_RESOURCE_LOADER_PATH, basePath);
            Velocity.init(p);

            VelocityContext context = new VelocityContext();
            context.put("list", getNames());

            Template template =  null;

            try
            {
                template = Velocity.getTemplate(templateFile);
            }
            catch( ResourceNotFoundException rnfe )
            {
                System.out.println("Example : error : cannot find template " + templateFile );
            }
            catch( ParseErrorException pee )
            {
                System.out.println("Example : Syntax error in template " + templateFile + ":" + pee );
            }

            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(System.out));

            if ( template != null)
                template.merge(context, writer);

            writer.flush();
            writer.close();
        }
        catch( Exception e )
        {
            System.out.println(e);
        }
    }
    
    @SuppressWarnings("unchecked")
	public ArrayList getNames()
    {
        ArrayList list = new ArrayList();

        list.add("ArrayList element 1");
        list.add("ArrayList element 2");
        list.add("ArrayList element 3");
        list.add("ArrayList element 4");

        return list;
    }
    

    public static void main(String[] args)
    {
        new Example("example.vm");
    }
}

运行结果如下：

Velocity is great!

    ArrayList element 1 is great!
    ArrayList element 2 is great!
    ArrayList element 3 is great!
    ArrayList element 4 is great!


    The condition is true!