1.SpringBoot利用自定义注解实现多数据源05-21 2.SpringBoot实现限流注解05-21 3.SpringBoot整合OSS文件上传05-31

4.通用权限系统-Spring-Boot-Starter07-08

Spring-Boot-Starter

自定义Starter

案例一：读取application.yml中的参数

1、创建

1、创建maven工程hello-spring-boot-starter

2、pom中添加依赖

<?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>     <groupId>org.example</groupId>    <artifactId>hello-spring-boot-starter</artifactId>    <version>1.0-SNAPSHOT</version>     <properties>        <maven.compiler.source>8</maven.compiler.source>        <maven.compiler.target>8</maven.compiler.target>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>    </properties>    <parent>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-parent</artifactId>        <version>2.2.2.RELEASE</version>        <relativePath/>    </parent>    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter</artifactId>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-autoconfigure</artifactId>        </dependency>    </dependencies></project>

3、创建HelloProperties
配置属性类，用于封装配置文件中配置的参数信息

package org.example.config; import org.springframework.boot.context.properties.ConfigurationProperties; /** * TODO 配置属性类，用于封装配置文件中配置的参数信息 * * @author ss_419 * @version 1.0 * @date 2023/7/8 13:55 */@ConfigurationProperties(prefix = "hello")public class HelloProperties {    private String name;    private String address;     public String getName() {        return name;    }     public void setName(String name) {        this.name = name;    }     public String getAddress() {        return address;    }     public void setAddress(String address) {        this.address = address;    }     @Override    public String toString() {        return "HelloProperties{" +                "name='" + name + '\'' +                ", address='" + address + '\'' +                '}';    }}

4、创建HelloService
这个类用于对读取到的参数进行一些业务上的操作

package org.example.service; /** * TODO * * @author ss_419 * @version 1.0 * @date 2023/7/8 14:03 */public class HelloService {    private String name;    private String address;     public HelloService(String name, String address) {        this.name = name;        this.address = address;    }     public String sayHello(){        return "你好！我的名字叫做"+name+"，地址是" + address;    }}

5、创建HelloServiceAutoConfiguration（用于自动配置HelloService对象）

package org.example.config; import org.example.service.HelloService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;import org.springframework.boot.context.properties.EnableConfigurationProperties;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration; /** * TODO 自动配置类 * 通过@Configuration + @Bean 实现自动创建对象 * * @author ss_419 * @version 1.0 * @date 2023/7/8 14:06 */@Configuration// 一定要加上这个注解，否则Spring找不到这个配置类@EnableConfigurationProperties(value = HelloProperties.class)public class HelloServiceAutoConfiguration {      private HelloProperties helloProperties;     // 通过构造方法注入配置属性对象HelloProperties    public HelloServiceAutoConfiguration(HelloProperties helloProperties) {        this.helloProperties = helloProperties;    }    // 实例化HelloService并载入Spring IOC 容器    @Bean    @ConditionalOnMissingBean// Spring中没有这个实例的时候再去创建    public HelloService helloService(){        return new HelloService(helloProperties.getName(), helloProperties.getAddress());    }}

6、在resources目录下创建META-INF/spring.factories

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\org.example.config.HelloServiceAutoConfiguration

7、将工程打包到maven仓库中

2、使用

1、创建项目，导入自定义starter

2、创建application.yml配置文件

3、创建启动类

package org.example; import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication; /** * TODO * * @author ss_419 * @version 1.0 * @date 2023/7/8 14:39 */@SpringBootApplicationpublic class HelloApplication {    public static void main(String[] args) {        SpringApplication.run(HelloApplication.class,args);    }}

4、创建测试Controller

package org.example.controller; import org.example.annotaion.MyLog;import org.example.service.HelloService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.GetMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController; /** * TODO * * @author ss_419 * @version 1.0 * @date 2023/7/8 14:36 */@RestController@RequestMapping("/hello")public class HelloController {     @Autowired    private HelloService helloService;     @GetMapping("/sayHello")        public String sayHello() {     return helloService.sayHello();    }}

5、测试

案例二：通过自动配置来创建一个拦截器对象，通过此拦截器对象来实现记录日志功能

1、创建

1、创建maven项目并且引入依赖

<?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>2.2.2.RELEASE</version>        <relativePath/>    </parent>    <groupId>org.example</groupId>    <artifactId>log-spring-boot-starter</artifactId>    <version>1.0-SNAPSHOT</version>     <properties>        <maven.compiler.source>8</maven.compiler.source>        <maven.compiler.target>8</maven.compiler.target>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>    </properties>    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter</artifactId>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-autoconfigure</artifactId>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>        </dependency>    </dependencies></project>

2、创建MyLog注解

package org.example.annotaion; import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target; @Target(ElementType.METHOD)@Retention(RetentionPolicy.RUNTIME)public @interface MyLog {    /**     * 方法描述     * @return     */    String desc() default "";}

3、创建日志拦截器

package org.example.interceptor; import org.example.annotaion.MyLog;import org.springframework.web.method.HandlerMethod;import org.springframework.web.servlet.ModelAndView;import org.springframework.web.servlet.handler.HandlerInterceptorAdapter; import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.lang.reflect.Method; /** * TODO 自定义日志拦截器 * * @author ss_419 * @version 1.0 * @date 2023/7/8 17:43 */public class MyLogInterceptor extends HandlerInterceptorAdapter {    private static final ThreadLocal<Long> startTimeThreadLocal = new ThreadLocal<>();// 记录时间毫秒值     /**     * 执行之前     * @param request     * @param response     * @param handler     * @return     * @throws Exception     */    @Override    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {        // 进行转换        HandlerMethod handlerMethod = (HandlerMethod) handler;        Method method = handlerMethod.getMethod();        // 获取方法上的注解MyLog        MyLog annotation = method.getAnnotation(MyLog.class);        if(annotation != null){            // 说明当前拦截到的方法上加入了MyLog注解            long currentTimeMillis = System.currentTimeMillis();            startTimeThreadLocal.set(currentTimeMillis);        }        return true;    }     /**     * 执行之后     * @param request     * @param response     * @param handler     * @param modelAndView     * @throws Exception     */    @Override    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {        HandlerMethod handlerMethod = (HandlerMethod) handler;        Method method = handlerMethod.getMethod();         // 获取方法上的注解MyLog        MyLog annotation = method.getAnnotation(MyLog.class);        if(annotation != null){            // 说明当前拦截到的方法上加入了MyLog注解            Long startTime = startTimeThreadLocal.get();            long endTime = System.currentTimeMillis();            long optTime =  endTime - startTime;             String requestUri = request.getRequestURI();            String methodName = method.getDeclaringClass().getName() + "."+                                method.getName()+"()";            String methodDesc = annotation.desc();             System.out.println("请求uri："+requestUri);            System.out.println("请求方法名："+methodName);            System.out.println("方法描述："+methodDesc);            System.out.println("方法执行时间："+optTime+"ms");         }        super.postHandle(request, response, handler, modelAndView);    }}

4、创建自动装配对象

package org.example.config; import org.example.interceptor.MyLogInterceptor;import org.springframework.context.annotation.Configuration;import org.springframework.web.servlet.config.annotation.InterceptorRegistry;import org.springframework.web.servlet.config.annotation.WebMvcConfigurer; /** * TODO * * @author ss_419 * @version 1.0 * @date 2023/7/8 18:08 */@Configurationpublic class MyLogAutoConfiguration implements WebMvcConfigurer {    /**     * 注册自定义日志拦截器     * @param registry     */    @Override    public void addInterceptors(InterceptorRegistry registry) {        registry.addInterceptor(new MyLogInterceptor());    }}

5、在resources下创建META-INF，在该文件夹下创建spring.factories
该配置文件用于扫描自动装配类

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\org.example.config.MyLogAutoConfiguration

2、使用

1、创建一个web项目，并且引入依赖，pom.xml如下：

<?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>     <groupId>org.example</groupId>    <artifactId>use-my-spring-boot-starter-demo</artifactId>    <version>1.0-SNAPSHOT</version>    <parent>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-parent</artifactId>        <version>2.2.2.RELEASE</version>        <relativePath/>    </parent>    <properties>        <maven.compiler.source>8</maven.compiler.source>        <maven.compiler.target>8</maven.compiler.target>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>    </properties>    <dependencies>        <dependency>            <groupId>org.example</groupId>            <artifactId>log-spring-boot-starter</artifactId>            <version>1.0-SNAPSHOT</version>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>        </dependency>        <dependency>            <groupId>org.example</groupId>            <artifactId>hello-spring-boot-starter</artifactId>            <version>1.0-SNAPSHOT</version>        </dependency>    </dependencies> </project>

2、创建测试Controller
在测试的方法上添加上自定义的MyLog注解，当该方法执行的时候就会在控制台输出对应信息

package org.example.controller; import org.example.annotaion.MyLog;import org.example.service.HelloService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.GetMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController; /** * TODO * * @author ss_419 * @version 1.0 * @date 2023/7/8 14:36 */@RestController@RequestMapping("/hello")public class HelloController {     @Autowired    private HelloService helloService;     @GetMapping("/sayHello")    @MyLog(desc = "sayHello方法")    public String sayHello() {     return helloService.sayHello();    }}

3、测试

到这里，对于自定义starter的案例就结束了。

文章版权归作者所有，未经允许请勿转载，侵权请联系 admin@trc20.tw 删除。

THE END

博客文章
# Spring