报错堆栈：
Illegal unquoted character ((CTRL-CHAR, code 10)): has to be escaped using backslash to be included in string value\n at [Source: (org.apache.cxf.transport.http.AbstractHTTPDestination$1); line: 3, column: 34
报错原因：
字符串中包含换行 ‘\n‘
解决办法：
1.在‘\n‘之前加转义符号‘\‘；
2.ObjectMapper MAPPER = new ObjectMapper();给MAPPER设置一个属性 MAPPER.configure(com.fasterxml.jackson.core.JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true);