class configured for Signature (provider: BC) cannot be found

java.security.NoSuchAlgorithmException: class configured for Signature (provider: BC) cannot be found. 
at java.security.Provider$Service.getImplClass(Provider.java:1649) 
at java.security.Provider$Service.newInstance(Provider.java:1592) 
at sun.security.jca.GetInstance.getInstance(GetInstance.java:236) 
at sun.security.jca.GetInstance.getInstance(GetInstance.java:206) 
at java.security.Signature.getInstance(Signature.java:362) 
at com.itapgo.mmc.util.unionpayutil.SecureUtil.signBySoft256(SecureUtil.java:292) 
at com.itapgo.mmc.manager.impl.UnionPayManagerImpl.createSign(UnionPayManagerImpl.java:276) 
at com.itapgo.mmc.manager.impl.UnionPayManagerImpl.unionPayRequest(UnionPayManagerImpl.java:223) 
at com.itapgo.mmc.manager.impl.UnionPayManagerImpl.creatOrder(UnionPayManagerImpl.java:172) 
at com.itapgo.mmc.service.impl.UnionPayChannelServiceImpl.createOrder(UnionPayChannelServiceImpl.java:72) 
at com.itapgo.mmc.service.impl.UnionPayChannelServiceImpl$$FastClassBySpringCGLIB$$c6e36c96.invoke(<generated>) 
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) 
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:746) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) 
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:88) 
at com.itapgo.mmc.aop.LogAopService.around(LogAopService.java:40) 
at sun.reflect.GeneratedMethodAccessor5951.invoke(Unknown Source) 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
at java.lang.reflect.Method.invoke(Method.java:498) 
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:644) 
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:633) 
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) 
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) 
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688) 
at com.itapgo.mmc.service.impl.UnionPayChannelServiceImpl$$EnhancerBySpringCGLIB$$187b80de.createOrder(<generated>) 
at com.itapgo.mmc.machinepayboxservice.impl.MachinePayServiceImpl.createOrder(MachinePayServiceImpl.java:190) 
at com.itapgo.mmc.machinepayboxservice.impl.MachinePayServiceImpl.scanPay(MachinePayServiceImpl.java:100) 
at com.itapgo.mmc.controller.PayController.createOrder(PayController.java:91) 
at com.itapgo.mmc.controller.PayController$$FastClassBySpringCGLIB$$51963fbc.invoke(<generated>) 
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) 
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:746) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) 
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:88) 
at com.itapgo.mmc.aop.PayAop.around(PayAop.java:34) 
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
at java.lang.reflect.Method.invoke(Method.java:498) 
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:644) 
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:633) 
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) 
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:88) 
at com.itapgo.mmc.aop.LogAopAction.around(LogAopAction.java:131) 
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
at java.lang.reflect.Method.invoke(Method.java:498) 
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:644) 
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:633) 
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) 
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) 
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688) 
at com.itapgo.mmc.controller.PayController$$EnhancerBySpringCGLIB$$3cd9a0ce.createOrder(<generated>) 
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
at java.lang.reflect.Method.invoke(Method.java:498) 
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209) 
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) 
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) 
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877) 
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783) 
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) 
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991) 
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) 
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974) 
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:877) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:650) 
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) 
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) 
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) 
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506) 
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) 
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) 
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962) 
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) 
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445) 
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115) 
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637) 
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) 
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) 
at java.lang.Thread.run(Thread.java:748) 
Caused by: java.lang.ClassNotFoundException: org.bouncycastle.jcajce.provider.asymmetric.rsa.DigestSignatureSpi$SHA256 
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1892) 
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1735) 
at java.security.Provider$Service.getImplClass(Provider.java:1636) 
... 98 more

解决方法：重启tomcat