MissingServletRequestParameterException : Calling post method in Angular.js - spring-mvc

Question

I'm trying to call a uri named ant/talk with post method in Angular.js.
In my code, I called using $http.post method in javascript with data.
$http.post('ant/create', {
content : $scope.content,
type : chatType,
point : point
}).then(function(response) { /* if successful request */ }
However, in spring controller just told me MissingServletRequestParameterException
#Controller
#RequestMapping("/ant/*")
public class AntTalkCont {
....
#RequestMapping(value = "/create", method = RequestMethod.POST, produces=MediaType.APPLICATION_JSON_UTF8_VALUE)
#ResponseBody
public String createProcess(HttpServletRequest request, Locale locale, Model model
, #RequestParam("content") String content) {
String content2 = request.getParameter("content");
logger.debug("content = {}", content);
logger.debug("content by request = {}", content2);
....
But I declared #RequestParam in java controller above, the spring controller throwed that exception. Though I removed RequestParam annotation and used request.getParameter also got null value.
I can append content on url like this ant/create?content='+$scope.content but the $scope.content can be longer than 512 bytes so I want to use data object in post request.
In spring controlller, how can I fix it properly?
Here is full stacktrace
16:59:17.546 [http-apr-30802-exec-80] DEBUG
o.s.w.s.m.m.a.ServletInvocableHandlerMethod - Error resolving argument
[3] [type=java.lang.String] HandlerMethod details: Controller
[kr.stocktalk.webchat.cont.AntTalkCont] Method [public
java.lang.String
kr.stocktalk.webchat.cont.AntTalkCont.createProcess(javax.servlet.http.HttpServletRequest,java.util.Locale,org.springframework.ui.Model,java.lang.String)]
org.springframework.web.bind.MissingServletRequestParameterException:
Required String parameter 'content' is not present at
org.springframework.web.method.annotation.RequestParamMethodArgumentResolver.handleMissingValue(RequestParamMethodArgumentResolver.java:195)
~[spring-web-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:104)
~[spring-web-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:121)
~[spring-web-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:161)
[spring-web-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:128)
[spring-web-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:114)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
[servlet-api.jar:na] at
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
[spring-webmvc-4.3.0.RELEASE.jar:4.3.0.RELEASE] at
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
[servlet-api.jar:na] at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
[catalina.jar:8.0.24] at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
[catalina.jar:8.0.24] at
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
[tomcat-websocket.jar:8.0.24] at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
[catalina.jar:8.0.24] at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
[catalina.jar:8.0.24] at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
[catalina.jar:8.0.24] at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
[catalina.jar:8.0.24] at
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
[catalina.jar:8.0.24] at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
[catalina.jar:8.0.24] at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
[catalina.jar:8.0.24] at
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:617)
[catalina.jar:8.0.24] at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
[catalina.jar:8.0.24] at
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
[catalina.jar:8.0.24] at
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
[tomcat-coyote.jar:8.0.24] at
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
[tomcat-coyote.jar:8.0.24] at
org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2503)
[tomcat-coyote.jar:8.0.24] at
org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2492)
[tomcat-coyote.jar:8.0.24] at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
[na:1.8.0_65] at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[na:1.8.0_65] at
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
[tomcat-util.jar:8.0.24] at java.lang.Thread.run(Thread.java:745)
[na:1.8.0_65]