无法读取文档:无法构造java.util的实例。HashMap:没有从字符串值反序列化的字符串参数构造器/工厂方法
[org.springframework.web.servlet.mvc.support.DefaultHandlerExceptionResolver]-Failed to read HTTP message: org.springframework.http.converter.HttpMessageNotReadableException: Could not read document: Can not construct instance of java.util.HashMap: no String-argument constructor/factory method to deserialize from String value ('state=1&description_type=1&description_title=%E8%B5%9Bsad&description=%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E6%89%93%E7%AE%97as')
at [Source: java.io.PushbackInputStream@1c440543; line: 1, column: 1]; nested exception is com.fasterxml.jackson.databind.JsonMappingException: Can not construct instance of java.util.HashMap: no String-argument constructor/factory method to deserialize from String value ('state=1&description_type=1&description_title=%E8%B5%9Bsad&description=%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E5%A5%A5%E8%B5%9B%E6%89%93%E7%AE%97as')
at [Source: java.io.PushbackInputStream@1c440543; line: 1, column: 1]
出现的原因是 前端传过来的是string类型的. 而我形参是hashmap的
解决办法: 形参变成 string类型的.
