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

sxyzy

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