Spring Boot - Building RESTful Web Service

学习文档：
https://www.tutorialspoint.com/spring_boot/spring_boot_building_restful_web_services.htm

添加依赖

为了构建RESTful Web Services,我们需要添加spring-boot-starter-web依赖。

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.restfulapio</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

实现控制器

@RestController

使用@RestController注解来定义RESTful web 服务，它提供JSON,XML等响应数据格式。
@RequestMapping(value=””)

使用@RequestMapping来定义Request的url入口
@RequestBody

使用@RequestBody来定义获取request请求中的content
@PathVariable(“”)

使用@PathVariable来获取用户自定义变量或动态变量
@RequestParam

使用@RequestParam来获取request请求的url中的参数

代码案例

package com.restfulapio.demo.controller;

import com.restfulapio.demo.bean.Product;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import sun.misc.Request;

import java.util.HashMap;
import java.util.Map;

@RestController
public class ProductServiceController {
    //模拟数据
    public static Map<String, Product> productRepo = new HashMap<>();
    static{
        Product honey = new Product();
        honey.setId("1");
        honey.setName("Honey");
        productRepo.put(honey.getId(), honey);

        Product almond = new Product();
        almond.setId("2");
        almond.setName("Almond");
        productRepo.put(almond.getId(), almond);

    }

    @RequestMapping(value = "/products")
    public ResponseEntity<Object> getProduct(){
        return new ResponseEntity<Object>(productRepo.values(), HttpStatus.OK);
    }

    @RequsetMapping(value = "/products",method= RequestMethod.POST)
    public ResponseEntity<Object> createProduct(@RequestBody Product product){
        productRepo.put(product.getId(),product);
        return new ResponseEntity<>("Product is created successfully",HttpStatus.CREATED);
    }
    @RequestMapping(value = "/products/{id}",method = RequestMethod.PUT)
    public ResponseEntity<Object> updateProduct(@PathVariable("id") String id,@RequestBody Product product){
        productRepo.remove(id);
        product.setId(id);
        productRepo.put(id, product);
        return new ResponseEntity<>("Product is updated successfully",HttpStatus.OK);
    }

    @RequestMapping(value = "/products/{id}",method = RequestMethod.DELETE)
    public ResponseEntity<Object> delete(@PathVariable("id") String id){
        productRepo.remove(id);
        return new ResponseEntity<>("Product is deleted successfully",HttpStatus.OK);
    }
}