解决方法：
1、没有绝对的方法，只能不断的测试和排查。
2、检查一下JSON数据和实体的字段结构是不是不一致导致的。比如JSON数据是数组，而实体字段为非数组。
参考：
https://stackoverflow.com/questions/21178215/can-not-deserialize-instance-of-task-out-of-start-array-token
https://stackoverflow.com/questions/19333106/jsonmappingexception-out-of-start-array-token
https://stackoverflow.com/questions/23674046/get-list-of-json-objects-with-spring-resttemplate/26796142#26796142
https://stackoverflow.com/questions/10719729/cannot-deserialize-instance-of-object-out-of-start-array-token-in-spring-3-rest/28449667#28449667
https://stackoverflow.com/questions/25510083/cannot-deserialize-instance-of-object-out-of-start-array-token-in-spring-webserv/25512128#25512128