Using a war under websphere 8.0 can sometimes throw this exception (In my specific case with jtopen libs) solved with the screen configuration:
ServletWrappe E com.ibm.ws.webcontainer.servlet.ServletWrapper service Uncaught service() exception thrown by servlet main: java.lang.NoSuchMethodError: com/ibm/as400/data/ProgramCallDocument.__jr_selector__(I[Ljava/lang/Object;)Ljava/lang/Object;
at com.fakeclass.genericinvokerweb.beprogram.BEProgram.output(BEProgram.java:217)
at com.fakeclass.genericinvokerweb.PCMLutils.buildOutPut(PCMLutils.java:128)
at com.fakeclass.genericinvokerweb.MainServlet.executeCallAs400(MainServlet.java:104)
at com.fakeclass.genericinvokerweb.MainServlet.doPost(MainServlet.java:86)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:595)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:668)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1230)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:779)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:478)
at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:178)
at com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:1071)
at com.ibm.ws.webcontainer.webapp.WebApp.__handleRequest(WebApp.java:3815)
at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java)
at com.ibm.ws.webcontainer.webapp.WebGroup.handleRequest(WebGroup.java:304)
at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:981)
at com.ibm.ws.webcontainer.WSWebContainer.handleRequest(WSWebContainer.java:1662)
at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:200)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:453)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewRequest(HttpInboundLink.java:515)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.processRequest(HttpInboundLink.java:306)
at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:84)
at com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:175)
at com.ibm.io.async.AbstractAsyncFuture.invokeCallback(AbstractAsyncFuture.java:217)
at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions(AsyncChannelFuture.java:161)
at com.ibm.io.async.AsyncFuture.completed(AsyncFuture.java:138)
at com.ibm.io.async.ResultHandler.complete(ResultHandler.java:204)
at com.ibm.io.async.ResultHandler.runEventProcessingLoop(ResultHandler.java:775)
at com.ibm.io.async.ResultHandler$2.run(ResultHandler.java:905)
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1702)
[17/03/16 16.41.28:730 CET] 00000050 SystemErr R 17-mar-2016 16.41.28 com.ibm.ws.webcontainer.servlet.ServletWrapper service
SEVERE: Uncaught service() exception thrown by servlet main: java.lang.NoSuchMethodError: com/ibm/as400/data/ProgramCallDocument.__jr_selector__(I[Ljava/lang/Object;)Ljava/lang/Object;
at com.fakeclass.genericinvokerweb.beprogram.BEProgram.output(BEProgram.java:217)
at com.fakeclass.genericinvokerweb.PCMLutils.buildOutPut(PCMLutils.java:128)
at com.fakeclass.genericinvokerweb.MainServlet.executeCallAs400(MainServlet.java:104)
at com.fakeclass.genericinvokerweb.MainServlet.doPost(MainServlet.java:86)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:595)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:668)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1230)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:779)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:478)
at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:178)
at com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:1071)
at com.ibm.ws.webcontainer.webapp.WebApp.__handleRequest(WebApp.java:3815)
at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java)
at com.ibm.ws.webcontainer.webapp.WebGroup.handleRequest(WebGroup.java:304)
at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:981)
at com.ibm.ws.webcontainer.WSWebContainer.handleRequest(WSWebContainer.java:1662)
at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:200)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:453)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewRequest(HttpInboundLink.java:515)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.processRequest(HttpInboundLink.java:306)
at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:84)
at com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:175)
at com.ibm.io.async.AbstractAsyncFuture.invokeCallback(AbstractAsyncFuture.java:217)
at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions(AsyncChannelFuture.java:161)
at com.ibm.io.async.AsyncFuture.completed(AsyncFuture.java:138)
at com.ibm.io.async.ResultHandler.complete(ResultHandler.java:204)
at com.ibm.io.async.ResultHandler.runEventProcessingLoop(ResultHandler.java:775)
at com.ibm.io.async.ResultHandler$2.run(ResultHandler.java:905)
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1702)