SSM前后端提交数据时报此错问题
相关出错代码如下
一月 26, 2020 11:46:45 下午 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet [springServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause
java.lang.NullPointerException
at com.zcw.my.shop.web.admin.web.controller.UserController.delete(UserController.java:99)
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:205)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
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:197)
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:494)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
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:1136)
at org.apache.coyote.AbstractProtocol
A
b
s
t
r
a
c
t
C
o
n
n
e
c
t
i
o
n
H
a
n
d
l
e
r
.
p
r
o
c
e
s
s
(
A
b
s
t
r
a
c
t
P
r
o
t
o
c
o
l
.
j
a
v
a
:
637
)
a
t
o
r
g
.
a
p
a
c
h
e
.
t
o
m
c
a
t
.
u
t
i
l
.
n
e
t
.
J
I
o
E
n
d
p
o
i
n
t
AbstractConnectionHandler.process(AbstractProtocol.java:637) at org.apache.tomcat.util.net.JIoEndpoint
A
b
s
t
r
a
c
t
C
o
n
n
e
c
t
i
o
n
H
a
n
d
l
e
r
.
p
r
o
c
e
s
s
(
A
b
s
t
r
a
c
t
P
r
o
t
o
c
o
l
.
j
a
v
a
:
6
3
7
)
a
t
o
r
g
.
a
p
a
c
h
e
.
t
o
m
c
a
t
.
u
t
i
l
.
n
e
t
.
J
I
o
E
n
d
p
o
i
n
t
SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor
W
o
r
k
e
r
.
r
u
n
(
T
h
r
e
a
d
P
o
o
l
E
x
e
c
u
t
o
r
.
j
a
v
a
:
617
)
a
t
o
r
g
.
a
p
a
c
h
e
.
t
o
m
c
a
t
.
u
t
i
l
.
t
h
r
e
a
d
s
.
T
a
s
k
T
h
r
e
a
d
Worker.run(ThreadPoolExecutor.java:617) at org.apache.tomcat.util.threads.TaskThread
W
o
r
k
e
r
.
r
u
n
(
T
h
r
e
a
d
P
o
o
l
E
x
e
c
u
t
o
r
.
j
a
v
a
:
6
1
7
)
a
t
o
r
g
.
a
p
a
c
h
e
.
t
o
m
c
a
t
.
u
t
i
l
.
t
h
r
e
a
d
s
.
T
a
s
k
T
h
r
e
a
d
WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
出现以上问题一般都是前端穿过来的参数（对象）调用了方法，而传过来的对象却为NULL，所以解决方法就是检查传过来的参数是否为空，再次确认前端与后端数据的交互