使用spring-boot的web服务

Question

我有一个像一样构建的Web服务

@RestController
public class GreetingController {
@PostMapping(path = "/greetingws")
public Foo greeting(@RequestBody Foo dto) {
return dto;
}
}

当我使用网络服务时，我确实喜欢这个

Foo f = new Foo("kkkkk");
ResponseEntity<String> t2 = restTemplate
.exchange("http://localhost:8080/greetingws", HttpMethod.POST, new HttpEntity<Foo>(f), String.class);

但它返回错误：

org.springframework.web.client.HttpClientErrorException$BadRequest: 400 : [{"timestamp":"2020-04-24T13:03:30.191+0000","status":400,"error":"Bad Request","message":"JSON parse error: Cannot construct instance of it.test.demo.controller.Foo (although at least one C... (7991 bytes)]

我的Foo类如下：

public class Foo {
private String nome;
public String getNome() {
return nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public Foo(String nome) {
super();
this.nome = nome;
}
@Override
public String toString() {
return "Foo [nome=" + nome + "]";
}
}

我在哪里出错？

Answer 1

Ciao Romeo：-(

看起来Foo中缺少默认构造函数，Spring无法反序列化请求
添加：

public Foo() {
}