VelocityViewServlet : Error processing the template

org.apache.velocity.exception.ResourceNotFoundException: Unable to find resource '/robots.txt'
	at org.apache.velocity.runtime.resource.ResourceManagerImpl.loadResource(ResourceManagerImpl.java:458)
	at org.apache.velocity.runtime.resource.ResourceManagerImpl.getResource(ResourceManagerImpl.java:341)
	at org.apache.velocity.runtime.RuntimeInstance.getTemplate(RuntimeInstance.java:831)
	at org.apache.velocity.runtime.RuntimeInstance.getTemplate(RuntimeInstance.java:813)
	at org.apache.velocity.app.VelocityEngine.getTemplate(VelocityEngine.java:470)
	at org.apache.velocity.tools.view.servlet.VelocityViewServlet.getTemplate(VelocityViewServlet.java:602)
	at org.apache.velocity.tools.view.servlet.VelocityViewServlet.handleRequest(VelocityViewServlet.java:536)
	at org.apache.velocity.tools.view.servlet.VelocityViewServlet.doRequest(VelocityViewServlet.java:461)
	at org.apache.velocity.tools.view.servlet.VelocityViewServlet.doGet(VelocityViewServlet.java:427)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
	at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:859)
	at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:574)
	at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1527)
	at java.lang.Thread.run(Thread.java:619)