title: Velocity does not replace Template's variables with VelocityContext
body: <p>I'm new to Velocity and found it was strange that template's variables did not be replaced by the value I put into the VelocityContext.</p>
  
  <p>The code is like this.</p>
  
  <pre><code>import java.io.StringWriter;
  import org.apache.velocity.app.VelocityEngine;
  import org.apache.velocity.Template;
  import org.apache.velocity.VelocityContext;
  
  public class Main {
  public static void main(String args[]){
      People XiaoMing=new People("XiaoMing", 11);
      VelocityEngine engine=new VelocityEngine();
      Template template=engine.getTemplate("/src/main/java/VMTemplate.vm");
      VelocityContext context=new VelocityContext();
      context.put("People", XiaoMing);
      StringWriter sw=new StringWriter(10000);
      template.merge(context, sw);
      System.out.println(sw.toString());
      }
  }
  
  class People{
    private String name;
    private int age;
    public People(String name,int age){
        this.name=name;
        this.age=age;
    }
  
    public String getName(){
        return name;
    }
  
    public int getAge(){
        return age;
     }
  }
  </code></pre>
  
  <p>The template is shown below.</p>
  
  <pre><code>#set($Name=$People.getName())
  #set($Age=$People.getAge())
  
  He is a $Age years old guy,and his name is $Name.
  </code></pre>
  
  <p>I do not know what is going wrong. Could you find out for me?</p>
  
  <p>Thank you very much!</p>