Spring Boot文档阅读笔记=Caching Data with Spring

柔情只为你懂 2023-01-09 15:44 194阅读 0赞

此篇博文展示了使用Spring去管理Bean开启缓存。

maven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>cn.it1995</groupId>
        <artifactId>CacheDataDemo</artifactId>
        <version>1.0</version>
    
        <properties>
            <java.version>1.8</java.version>
        </properties>
    
        <dependencies>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
                <version>2.1.10.RELEASE</version>
            </dependency>
    
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <optional>true</optional>
                <version>1.18.12</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-cache</artifactId>
                <version>2.1.10.RELEASE</version>
            </dependency>
    
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                    <version>2.2.2.RELEASE</version>
                </plugin>
            </plugins>
        </build>
    
    </project>

创建Book的模型，用于查询时返回对象：

Book.java

package cn.it1995.object;
    
    import lombok.Data;
    
    @Data
    public class Book {
    
        private String isbn;
        private String title;
    
        public Book(String isbn, String title) {
    
            this.isbn = isbn;
            this.title = title;
        }
    }

创建Book仓库接口：

package cn.it1995.repository;
    
    import cn.it1995.object.Book;
    
    public interface BookRepository {
    
        Book getByIsbn(String isbn);
    }

接口的实现：

package cn.it1995.repository.impl;
    
    import cn.it1995.object.Book;
    import cn.it1995.repository.BookRepository;
    import org.springframework.cache.annotation.Cacheable;
    import org.springframework.stereotype.Component;
    
    @Component
    public class SimpleBookRepository implements BookRepository {
    
    
        @Override
    //    @Cacheable("books")
        public Book getByIsbn(String isbn) {
    
            simulateSlowService();
            return new Book(isbn, "Some book");
        }
    
        private void simulateSlowService(){
    
            try{
    
                long time = 3000L;
                Thread.sleep(time);
            }
            catch(InterruptedException e){
    
                e.printStackTrace();
            }
        }
    }

入口函数：

package cn.it1995;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.cache.annotation.EnableCaching;
    
    @SpringBootApplication
    //@EnableCaching
    public class CacheDataDemoMain {
    
        public static void main(String[] args){
    
            SpringApplication.run(CacheDataDemoMain.class);
        }
    }

调用如下：

package cn.it1995;
    
    import cn.it1995.repository.BookRepository;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.boot.CommandLineRunner;
    import org.springframework.stereotype.Component;
    
    @Component
    public class AppRunner implements CommandLineRunner {
    
        private static final Logger logger = LoggerFactory.getLogger(AppRunner.class);
    
        private final BookRepository bookRepository;
    
        public AppRunner(BookRepository bookRepository){
    
            this.bookRepository = bookRepository;
        }
    
        @Override
        public void run(String... args){
    
    
            logger.info("......Fetching books......");
            logger.info("isbn-1234 -->" + bookRepository.getByIsbn("isbn-1234"));
            logger.info("isbn-4567 -->" + bookRepository.getByIsbn("isbn-4567"));
            logger.info("isbn-1234 -->" + bookRepository.getByIsbn("isbn-1234"));
            logger.info("isbn-4567 -->" + bookRepository.getByIsbn("isbn-4567"));
            logger.info("isbn-1234 -->" + bookRepository.getByIsbn("isbn-1234"));
            logger.info("isbn-1234 -->" + bookRepository.getByIsbn("isbn-1234"));
        }
    }

开启缓存只要将上面注释放开就可以了。

未开启缓存时，程序运行如下：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70][]

开启缓存后，程序运行如下：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70 1][]

从中可以看到，如果查找相同的数据，开启缓存后，基本上都是秒回。

源码打包下载地址：

[https://github.com/fengfanchen/Java/tree/master/CacheDataDemo][https_github.com_fengfanchen_Java_tree_master_CacheDataDemo]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70]: /images/20221119/85f7aaaf13b64b70a665a316895d75bf.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxNzg0NDI3NjE_size_16_color_FFFFFF_t_70 1]: /images/20221119/8dc8747d9e9243af98105e7f0b479928.png
[https_github.com_fengfanchen_Java_tree_master_CacheDataDemo]: https://github.com/fengfanchen/Java/tree/master/CacheDataDemo