org.springframework.web.client.HttpClientErrorException: 404 Not Found
原因1：mediaTypeError(ContentType)
原因2：server端出现错误（json的key不能为null）
com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.lang.String out of START_OBJECT token
bean 不能被反序列化
Can not deserialize instance of java.util.ArrayList out of START_OBJECT token
ACCEPT_SINGLE_VALUE_AS_ARRAY设定
com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.lang.String out of START_OBJECT token
org.springframework.web.client.HttpClientErrorException: 406 Not Acceptable
jackson-core、jackson-databind、mediaType不一致(ContentType)
原文：http://blog.51cto.com/xinzhilian/2052814