无法在Spring REST控制器中将Map用作JSON @RequestParam [英] Cannot use Map as a JSON @RequestParam in Spring REST controller
本文介绍了无法在Spring REST控制器中将Map用作JSON @RequestParam的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
此控制器
@GetMapping("temp")
public String temp(@RequestParam(value = "foo") int foo,
@RequestParam(value = "bar") Map<String, String> bar) {
return "Hello";
}
产生以下错误:
{
"exception": "org.springframework.web.method.annotation.MethodArgumentConversionNotSupportedException",
"message": "Failed to convert value of type 'java.lang.String' to required type 'java.util.Map'; nested exception is java.lang.IllegalStateException: Cannot convert value of type 'java.lang.String' to required type 'java.util.Map': no matching editors or conversion strategy found"
}
我想要的是使用bar
参数传递一些JSON:
http://localhost:8089/temp?foo = 7& bar =%7B%22a%22%3A%22b%22%7D ,其中foo
是7
,而bar
是{"a":"b"}
为什么Spring无法进行这种简单的转换?请注意,如果将地图用作POST
请求的@RequestBody
,则它起作用.
What I want is to pass some JSON with bar
parameter:
http://localhost:8089/temp?foo=7&bar=%7B%22a%22%3A%22b%22%7D, where foo
is 7
and bar
is {"a":"b"}
Why is Spring not able to do this simple conversion? Note that it works if the map is used as a @RequestBody
of a POST
request.
推荐答案
以下是有效的解决方案:
只需将自String
到Map
的自定义转换器定义为@Component
.然后它将自动注册:
Here is the solution that worked:
Just define a custom converter from String
to Map
as a @Component
. Then it will be registered automatically:
@Component
public class StringToMapConverter implements Converter<String, Map<String, String>> {
@Override
public Map<String, Object> convert(String source) {
try {
return new ObjectMapper().readValue(source, new TypeReference<Map<String, String>>() {});
} catch (IOException e) {
throw new RuntimeException(e.getMessage());
}
}
}
这篇关于无法在Spring REST控制器中将Map用作JSON @RequestParam的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文