write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.header.HeaderWriterFilter$HeaderWriterResponse, write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.header.HeaderWriterFilter$HeaderWriterResponse, fieldName : response, write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.context.HttpSessionSecurityContextRepository$SaveToSessionResponseWrapper, fieldName : response, write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.firewall.FirewalledResponse, fieldName : response, getOutputStream() has already been called for this response

 write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.header.HeaderWriterFilter$HeaderWriterResponse, write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.header.HeaderWriterFilter$HeaderWriterResponse, fieldName : response, write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.context.HttpSessionSecurityContextRepository$SaveToSessionResponseWrapper, fieldName : response, write javaBean error, fastjson version 1.2.54, class org.springframework.security.web.firewall.FirewalledResponse, fieldName : response, getOutputStream() has already been called for this response 

因为 getOutputStream() 被调用过了，然后在序列化的时候再被 FastJSON 调用，就会出现异常。
可以将 org.springframework.security.web.header.HeaderWriterFilter$HeaderWriterResponse 这个对象排除掉，不要序列化。