DocConverter转换类取不到值?报错

//调用转换类DocConverter,并将需要转换的文件传递给该类的构造方法
	         DocConverter d = new DocConverter(converfilename);
	         //调用conver方法开始转换，先执行doc2pdf()将office文件转换为pdf;再执行pdf2swf()将pdf转换为swf;
	     	 d.conver();
	     	 //调用getswfPath()方法，打印转换后的swf文件路径
	         System.out.println(d.getswfPath()+"1");
	     	 //生成swf相对路径，以便传递给flexpaper播放器
			String swfpath = "upload"+d.getswfPath().substring(d.getswfPath().lastIndexOf("/")); 
			//String swfpath = d.getswfPath();
			System.out.println(swfpath);

报错如下：

SyntaxError: invalid syntax
****swf转换成功，文件输出:C:\Users\Administrator\Documents\workspace-sts-3.7.0.RELEASE\.metadata\.plugins\org.eclipse.wst.server.core\tmp1\wtpwebapps\ctcesims\upload\openofficd3.swf****

五月 13, 2016 4:16:32 下午 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet [jsp] in context with path [/ctcesims] threw exception [java.lang.StringIndexOutOfBoundsException: String index out of range: -1] with root cause
java.lang.StringIndexOutOfBoundsException: String index out of range: -1
    at java.lang.String.substring(String.java:1871)
    at org.apache.jsp.docUploadConvertAction_jsp._jspService(docUploadConvertAction_jsp.java:110)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:744)