java web 基础springboot

1.SprintBootj集成mybaits 连接数据库

pom.xml文件添加依赖

		
			mysql
			mysql-connector-java
			8.0.30
		


		
			org.mybatis.spring.boot
			mybatis-spring-boot-starter
			2.0.0
		
	

mapper文件 数据持久层

• RESTFul风格

简单的说就是没有方法体，直接拼接地址

@GetMapping(value = "/studentrestfull/detail/{id}/{name}")
    public Object student1(@PathVariable("id") Integer id,
                           @PathVariable("name") String name)

注意的点：

//以上代码restful请求不容易区分请求类型造成错误
//路径冲突；通常在RESTFUL风格中方法的请求方式会按照增删改查进行区分
//路径冲突；更改请求路径
//RESTFul请求风格要求路径中出现都是名词，不要是动词

@RestController
public class StudentControllerRestful {

    @RequestMapping(value = "studentrestfull")
    public Object studentrestfull(Integer id,String name){

        Student student = new Student();
        student.setId(id);
        student.setName(name);
        return student;
    }

    //restful请求风格 (get) http://127.0.0.1:8081/springboot/studentrestfull/detail/11/lisi
//    @RequestMapping(value = "/studentrestfull/detail/{id}/{name}")
    @GetMapping(value = "/studentrestfull/detail/{id}/{name}")
    public Object student1(@PathVariable("id") Integer id,
                           @PathVariable("name") String name){
        Map retMap = new HashMap<>();
        retMap.put("id",id);
        retMap.put("name",name);
        return retMap;
    }

    //restful请求风格  使用postman进行数据验证
//    @RequestMapping(value = "/studentrestfull/detail/{id}/{status}")
    @DeleteMapping(value = "/studentrestfull/detail/{id}/{status}")
    public Object student2(@PathVariable("id") Integer id,
                           @PathVariable("status") String status){
        Map retMap = new HashMap<>();
        retMap.put("id",id);
        retMap.put("status",status);
        return retMap;
    }

    //以上代码restful请求不容易区分请求类型造成错误
    //通常在RESTFUL风格中方法的请求方式会按照增删改查进行区分


    //city与status进行冲突
//    @DeleteMapping(value = "/studentrestfull/detail/{id}/{city}")
    @DeleteMapping(value = "/studentrestfull/{id}/detail/{city}")
    public Object student3(@PathVariable("id") Integer id,
                           @PathVariable("city") String city){
        Map retMap = new HashMap<>();
        retMap.put("id",id);
        retMap.put("city",city);
        return retMap;
    }

}

• 集成redis

        1.添加依赖 （pom文件）

            org.springframework.boot
            spring-boot-starter-data-redis
 

         2.核心配置文件中添加redis配置(application.properties文件)

spring.redis.host=127.0.0.1
spring.redis.port= 6379
spring.redis.password= 123456

 redis控制器

@Controller
public class StudentControllerRedis {
    @Autowired
    private StudentService studentService;

    @RequestMapping(value = "/put")
    public @ResponseBody Object putredis(String key,String value){
        studentService.put(key,value);
        return "写入成功";
    }

    @RequestMapping(value = "/get")
    public @ResponseBody String get(){
        String count = studentService.get("name");
        return "数据count为：" +count;
    }
}

 redis接口

public interface StudentService {

//    根据学生id查询学生  这是接口  需要实现类StudentServiceImpl
    Student querStudengById(Integer id);
//修改学生id
    int updateStudentById(Student student);


    //将值存放到server中
    void put(String key, String value);

    //从redis获取count值
    String get(String count);
}

 redis接口实现层

//StudentService 的实现类  业务层
@Service
public class StudentServiceImpl implements StudentService {
    @Autowired  //加载对象
    private StudentMapper studentMapper;

    @Autowired  //加载对象
    private RedisTemplate redisTemplate;

    @Override
    public Student querStudengById(Integer id) {
        return studentMapper.selectByPrimaryKey(id);
    }

    @Transactional  //事物，int a = 10/0; 执行出错，数据库不改变
    @Override
    public int updateStudentById(Student student) {
        int i = studentMapper.updateByPrimaryKeySelective(student);
//        int a = 10/0;
        return i;
    }

    @Override
    public void  put(String key,String value){
        redisTemplate.opsForValue().set(key,value);  //操作string
    }


    @Override
    public String get(String key){
        String count = (String) redisTemplate.opsForValue().get(key);
        return count;
    }




}

•  SpringBoot 集成Dubbo 分布式框架  (服务提供者consumer)
• 

         

 pom文件

    com.alibaba.spring.boot
    dubbo-spring-boot-starter
    2.0.0




    com.101tec
    zkclient
    0.10

配置文件

#设置Dubbo的配置
spring.application.name=022-springboot-dubbo-consumer


#当前工程是一个服务的提供者
spring.dubbo.server = true

#设置注册中心
spring.dubbo.registry=zookeeper://127.0.0.1:2181

web中的控制文件

@Controller
public class Studentconsumer {
    //  dubbo:reference interface="" version="" check=""
    @Reference(interfaceClass = StudentServiceDobbu.class,version = "1.0.0",check = false)
    private StudentServiceDobbu studentServiceDobbu;

    //http://127.0.0.1:8081/student/count
    @RequestMapping(value = "student/count")
    public @ResponseBody Object studnetCount(){
        Integer allStudnetCount = studentServiceDobbu.querAllStudentCount();
        return "学生总人数" + allStudnetCount;
    }
}

dubbo接口

package com.javawebs.springboot_014.service;

public interface StudentServiceDobbu {

//    获取学生总人数
    Integer querAllStudentCount();
}

impl接口实现类

package com.javawebs.springboot_014.service.impl;

import com.alibaba.dubbo.config.annotation.Service;
import com.javawebs.springboot_014.service.StudentServiceDobbu;
import org.springframework.stereotype.Component;

@Component //加载到springboot
@Service(interfaceClass = StudentServiceDobbu.class,version = "1.0.0",timeout = 15000) //暴露接口

public class StudentServiceDobbuImpl implements StudentServiceDobbu {
    @Override
    public Integer querAllStudentCount() {
        //调用数据持久层

        return 10000;
    }
}

启动器

@SpringBootApplication  //开启spring配置
@EnableDubboConfiguration  //开启Dobbu注解配置
@MapperScan(basePackages = "com.javawebs.springboot_014.mapper")  //开启扫描mapper接口的包和子包 总的
//@EnableTransactionManagement   //可选项  加不加事物都生效

public class Springboot014Application {

    public static void main(String[] args) {
        SpringApplication.run(Springboot014Application.class, args);
    }

}