Spring boot入门之web开发基础教程

普通web项目

• 使用软件：IDEA
• 新建项目，file->new->project

• 点击next，配置自己的项目信息，其他不用管
  
• 继续next，选择web->spring web
  
• next，不用做修改，直接finish
  
• 在com.leon.zero_one包下新建一个package，命名为controler，包下新建类：HelloController

package com.leon.zero_one.controler;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.HashMap;

@Controller
public class HelloController {
    @RequestMapping("/")
    @ResponseBody
    public String getHello() {
        return "hello Spring Boot！这是一个用Spring Boot开发的网站。";
    }
}

• 点击运行，在浏览器地址栏输入localhost:8080查看效果
  

Restful风格的web接口

• 使用软件：IDEA
• 新建一个web项目
• 功能：简单的计数器，实现初始化计数器，修改计数器和查询计数器
• 构造下面这样的项目结构
  
• 写入代码
  Count:

package com.couter.demo.bean;

public class Count {
    private int count;

    public int getCount() {
        return count;
    }

    public void setCount(int count) {
        this.count = count;
    }
}

ResourceController:

package com.couter.demo.controller;

import com.couter.demo.bean.Count;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import com.couter.demo.service.ResourceService;

@RestController
public class ResourceController {

    @Autowired
    ResourceService resourceService;

    @RequestMapping(value = "/me/count", method = RequestMethod.PUT)
    @ResponseBody
    public void initCount(@RequestBody Count count){
        resourceService.initCount(count);
    }

    @RequestMapping(value = "/me/count", method = RequestMethod.POST)
    @ResponseBody
    public void modifyCount(@RequestBody Count count){
        resourceService.addCount(count);
    }

    @RequestMapping(value = "/me/count", method = RequestMethod.GET)
    @ResponseBody
    public  Count getCount()
    {
        return resourceService.getCount();
    }
}

ResourceService：

package com.couter.demo.service;

import com.couter.demo.bean.Count;
import com.couter.demo.manager.ResourceManager;
import org.springframework.stereotype.Service;

@Service
public class ResourceService {
    public void addCount(Count count){
        if (count != null){
            ResourceManager.getInstance().addCount(count.getCount());
        }
    }

    public void minusCount(Count count){
        if (count != null) {
            ResourceManager.getInstance().minusCount(count.getCount());
        }
    }

    public Count getCount()
    {
        Count count = new Count();
        count.setCount(ResourceManager.getInstance().getCount());
        return count;
    }

    public void initCount(Count count){
        if (count != null) {
            ResourceManager.getInstance().initCount(count.getCount());
        }
    }
}

ResourceManager：

package com.couter.demo.manager;

public class ResourceManager {
    private int count = 0;

    private static ResourceManager instance = new ResourceManager();

    private ResourceManager(){}

    public static ResourceManager getInstance(){
        return instance;
    }

    public synchronized void addCount(int i){
        count = count + i;
    }

    public synchronized  void minusCount(int i){
        count = count -i;
    }

    public int getCount(){
        return count;
    }

    public void initCount(int i){
        count = i;
    }
}

DemoApplication是IDEA自动生成的，无需修改

• 启动服务
  在DemoApplication类里点击运行，服务启动正常
  

测试

• 使用软件：PostMan
• url统一填/me/count，共使用三个接口进行测试，分别为get，post，put。get查询初始值为0：
  
• 初始化并修改
  初始化为100
  
  查询
  
  修改
  
  再次查询
  
  完成！