⭐ springBoot输出hello world

创建HelloController

package com.lackoxygen.spring.controller;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloController {
    @GetMapping(value = "hello")
    public String hello() {
        return "hello world";
    }
}

请求方式注解

  • org.springframework.web.bind.annotation.*
注解名 限制请求方法
RequestMapping 默认不限制或通过method
GetMapping GET
PostMapping POST
PutMapping PUT
DeleteMapping DELETE
PatchMapping PATCH

RestController

org.springframework.web.bind.annotation

  • 相当于@Controller 和 @ResponseBody注解的结合

请求方法

org.springframework.web.bind.annotation.RequestMethod

  • RequestMethod.GET
  • RequestMethod.POST
  • RequestMethod.PUT
  • RequestMethod.DELETE
  • RequestMethod.OPTIONS
  • RequestMethod.HEAD
  • RequestMethod.PATCH
  • RequestMethod.TRACE

返回

返回String类型需要注明produces 为 application/json;charset=utf8否则可能出现乱码，返回对象无需注明，返回对象会执行spring默认的json解析器

package com.lackoxygen.spring.controller;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.http.MediaType;

@RestController
public class HelloController {
    @GetMapping(value = "hello", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
    public String hello() {
        return "hello world";
    }
}

启动访问http://127.0.0.1:8080/hello

  • 默认端口8080