velocity使用中出现org.apache.velocity.exception.ResourceNotFoundException的解决办法

在使用velocity过程中，总是出现.ResourceNotFoundException异常，找不到模板.vm文件。现公布解决办法：

import org.apache.velocity.app.Velocity;
import org.apache.velocity.app.VelocityEngine;
import java.io.StringWriter;
import java.util.Properties;

import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
public class VelocityTest {

	public static void main(String[] args) {
		try {
			/* first, get and initialize an engine */
			VelocityEngine ve = new VelocityEngine();
			Properties properties = new Properties();
			String basePath = "src/com/worthtech/app/test";//这里需要这样写路径！！！
			// 设置模板的路径
			properties.setProperty(Velocity.FILE_RESOURCE_LOADER_PATH, basePath);
			// 初始花velocity 让设置的路径生效
			ve.init(properties);
			/* next, get the Template */
			Template t = ve.getTemplate("vm.vm");
			/* create a context and add data */
			VelocityContext context = new VelocityContext();
			context.put("name", "DingDangXiaoMa");
			context.put("site", "http://www.sun.com");
			/* now render the template into a StringWriter */
			StringWriter writer = new StringWriter();
			t.merge(context, writer);
			/* show the World */
			System.out.println(writer.toString());
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

}

研究velocity源码：

public synchronized InputStream getResourceStream(String name)
    throws ResourceNotFoundException
  {
    InputStream result = null;

    if ((name == null) || (name.length() == 0))
    {
      throw new ResourceNotFoundException("No template name provided");
    }

    try
    {
      ClassLoader classLoader = super.getClass().getClassLoader();
      result = classLoader.getResourceAsStream(name);
    }
    catch (Exception fnfe)
    {
      throw new ResourceNotFoundException(fnfe.getMessage());
    }

    return result;
  }

关键是
ClassLoader classLoader = super.getClass().getClassLoader();
result = classLoader.getResourceAsStream(name);
这两行代码。是在你的Classpath下去load， 所以必须保证vm文件存在于WEB-INF/classes 下