初识SpringBoot

一.SpringBoot认识

SpringBoot 它Spring里面提供一个框架，或者一些maven的集合，（提供很多starter）
我们通过它，可以快速的构建项目 编译和部署，监控；

二.SpringBoot对SpringMVC的支持

如果需要跑一个springweb程序，只需要添加spring-boot-starter-web依赖

<dependency>
    <groupId>org.springframework.bootgroupId>
    <artifactId>spring-boot-starter-webartifactId>
dependency>

• 新建一个Controller类
  @RestController的效果 相当于在方法上面@ResponseBody

@RestController
public class HelloController {

    @RequestMapping("/hello")
    public String hello(){
        return "hello world222";
    }
}

• 新建启动类(App – Main方法)

@SpringBootApplication
public class SpringBootApp {
    public static void main(String[] args) {
        SpringApplication.run(SpringBootApp.class);
    }
}

• 测试代码
  运行:App
  浏览器：http://localhost:8080/hello

三.SpringBoot对Jsp的支持

需要的依赖

<dependency>
		<groupId>org.springframework.bootgroupId>
		<artifactId>spring-boot-starter-webartifactId>
	dependency>

	
	<dependency>
		<groupId>javax.servletgroupId>
		<artifactId>javax.servlet-apiartifactId>
		<scope>providedscope>
	dependency>

	<dependency>
		<groupId>javax.servletgroupId>
		<artifactId>jstlartifactId>
	dependency>

	
	<dependency>
		<groupId>org.springframework.bootgroupId>
		<artifactId>spring-boot-starter-tomcatartifactId>
		<scope>providedscope>
	dependency>
	<dependency>
		<groupId>org.apache.tomcat.embedgroupId>
		<artifactId>tomcat-embed-jasperartifactId>
		<scope>providedscope>
	dependency>

配置application.properties – 不要写错

• application.properties：

# 页面默认前缀目录
spring.mvc.view.prefix=/WEB-INF/jsp/
# 响应页面默认后缀
spring.mvc.view.suffix=.jsp

• 启动 配置run -配置当前模块的工作目录
  

四. SpringBoot对freemark 支持

需要的依赖

<dependencies>
	<dependency>
		<groupId>org.springframework.bootgroupId>
		<artifactId>spring-boot-starter-webartifactId>
	dependency>
	<dependency>
		<groupId>org.springframework.bootgroupId>
		<artifactId>spring-boot-starter-freemarkerartifactId>
	dependency>
dependencies>

配置：application.properties

• application.properties

spring.freemarker.tempalte-loader-path=classpath:/templates
#        关闭缓存，及时刷新，上线生产环境需要修改为true
spring.freemarker.cache=false
spring.freemarker.charset=UTF-8
spring.freemarker.check-template-location=true
spring.freemarker.content-type=text/html
spring.freemarker.expose-request-attributes=true
spring.freemarker.expose-session-attributes=true
spring.freemarker.request-context-attribute=request
spring.freemarker.suffix=.ftl
注意一点：如果使用上面的配置 模板的名称使用templates

5.SpringBoot对json支持

• @RestControll -->在方法上面就不用配置@ResponseBody
• @Controller + @ResponseBody
• 返回String
• 返回对象 --时间类型加 @JsonFormat
• 返回List

6.配置ymal的方式

• application.yml --特点：结构比较清晰，容易阅读 ，主要配置文件
  比如 server：
  ----------- port : 9001

7.SpringBoot测试的使用

需要的依赖

<dependency>
    <groupId>junitgroupId>
    <artifactId>junitartifactId>
    <version>4.12version>
dependency>
<dependency>
    <groupId>org.springframework.bootgroupId>
    <artifactId>spring-boot-starter-webartifactId>
dependency>

<dependency>
    <groupId>org.springframework.bootgroupId>
    <artifactId>spring-boot-starter-testartifactId>
dependency>

• 测试类

@RunWith(SpringRunner.class)
@SpringBootTest(classes = SpringTestApp.class)
public class SpringTest {
    @Test
    public void test() throws Exception{
        System.out.println(111);
    }
}

8.SpringBoot对springjdbc的支持

需要的依赖

<dependencies>
    <dependency>
        <groupId>junitgroupId>
        <artifactId>junitartifactId>
        <version>4.12version>
    dependency>
    
    <dependency>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-webartifactId>
    dependency>
    <dependency>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-testartifactId>
    dependency>

    <dependency>
        <groupId>mysqlgroupId>
        <artifactId>mysql-connector-javaartifactId>
    dependency>
    <dependency>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-jdbcartifactId>
    dependency>
dependencies>

项目结构

• 持久层接口

public interface IUserDao {

    public void save(User user);
}

• 持久层实现

@Repository
public class UserDaoImpl implements IUserDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Override
    public void save(User user) {
        jdbcTemplate.update("insert into t_user(name) values (?)",user.getName());
    }
}

9.SpringBoot对Mybatis支持

需要的依赖

<dependency>
	<groupId>org.springframework.bootgroupId>
	<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
	<groupId>org.springframework.bootgroupId>
	<artifactId>spring-boot-starter-testartifactId>
dependency>

<dependency>
		<groupId>mysqlgroupId>
		<artifactId>mysql-connector-javaartifactId>
dependency>	


<dependency>
	<groupId>org.mybatis.spring.bootgroupId>
	<artifactId>mybatis-spring-boot-starterartifactId>
	<version>1.1.1version>
dependency>
	
<dependency>
	<groupId>com.github.pagehelpergroupId>
	<artifactId>pagehelperartifactId>
	<version>4.1.0version>
dependency>	

• 持久层

public interface UserMapper {

    @Insert("insert into t_user(name) values(#{name})")
    public void save(User user);

    public void saveXml(User user);

    //分页查询
    public List<User> queryPageAll();
}

• service层实现

@Service
@Transactional(propagation = Propagation.SUPPORTS)
public class UserServiceImpl implements IUserService {

    @Autowired
    private UserMapper userMapper;


    @Override
    @Transactional(propagation = Propagation.REQUIRED,readOnly = false)
    public void save(User user) {
        userMapper.save(user);
    }

    @Override
    public void saveXml(User user) {
        userMapper.saveXml(user);
    }

    @Override
    public List<User> queryPageAll() {
        PageHelper.startPage(2,3);
        List<User> users = userMapper.queryPageAll();
        return users;
    }
}

• 启动类

@SpringBootApplication
@MapperScan("cn.wing.mapper")
public class SpringMybatisApp {

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

需要在这里开启mapper层的扫描

• 分页插件

@Configuration
public class MyBatisConfiguration {

    @Bean
    public PageHelper pageHelper(){
        PageHelper pageHelper = new PageHelper();
        Properties p = new Properties();
        //配置分页的参数设置
        //和startPage中的pageNum效果一样
        p.setProperty("offsetAsPageNum", "true");
        //设置为true时，使用RowBounds分页会进行count查询
        p.setProperty("rowBoundsWithCount", "true");
        // 启用合理化时，如果pageNum<1会查询第一页，如果pageNum>pages会查询最后一页
        p.setProperty("reasonable", "true");
        pageHelper.setProperties(p);
        return pageHelper;
    }

}