springboot整合mongodb（二）

迈不过友情╰ 2021-12-11 09:47 305阅读 0赞

**背景：在[springboot整合mongodb（一）][springboot_mongodb]基础上进行**

**从mongdb中取出文件**

### 一、创建MyFile实体类 ###

package com.zsx.entity;
    
    import java.util.Arrays;
    
    public class MyFile {
    
        private byte[] file;
    
        public MyFile() {
        }
    
        public MyFile(byte[] file) {
            this.file = file;
        }
    
        public byte[] getFile() {
            return file;
        }
    
        public void setFile(byte[] file) {
            this.file = file;
        }
    
        @Override
        public String toString() {
            return "MyFile{" +
                    "file=" + Arrays.toString(file) +
                    '}';
        }
    }

### 二、FileController中添加api接口 ###

@GetMapping("/image/{id}")
        public ResponseEntity getFile(@PathVariable("id") String id) {
            MyFile file = fileService.getMyFile(id);
            if (file == null) {
                return new ResponseEntity("fail", HttpStatus.INTERNAL_SERVER_ERROR);
            }
            return new ResponseEntity(file, HttpStatus.OK);
        }

### 三、FileService生成对应的方法 ###

MyFile getMyFile(String id);

### 四、FileServiceImpl类中实现该方法 ###

@Override
        public MyFile getMyFile(String id) {
            return new MyFile(fileDao.getById(id));
        }

### 五、FileDao中进行数据处理 ###

@Autowired
        private GridFSBucket gridFSBucket;
    
        public byte[] getById(String id) {
            GridFSDownloadStream downloadStream = null;
            try {
                // 根据id查询文件
                GridFSFile gridFSFile = gridFsTemplate.findOne(Query.query(Criteria.where("_id").is(id)));
                // 打开流下载对象
                downloadStream =  gridFSBucket.openDownloadStream(gridFSFile.getObjectId());
                return downloadStream.readAllBytes();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                if (downloadStream != null) {
                    downloadStream.close();
                }
            }
            return null;
        }

### 六、创建事务配置类TransactionalConfig ###

package com.zsx.config;
    
    import com.mongodb.client.MongoDatabase;
    import com.mongodb.client.gridfs.GridFSBucket;
    import com.mongodb.client.gridfs.GridFSBuckets;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.data.mongodb.MongoDbFactory;
    import org.springframework.data.mongodb.MongoTransactionManager;
    import org.springframework.data.mongodb.core.convert.MongoConverter;
    import org.springframework.data.mongodb.gridfs.GridFsTemplate;
    
    @Configuration
    public class TransactionalConfig {
    
        @Autowired
        private MongoConverter mongoConverter;
    
        @Bean
        public GridFsTemplate gridFsTemplate(MongoDbFactory mongoDbFactory) {
            return new GridFsTemplate(mongoDbFactory, mongoConverter);
        }
    
        @Bean
        public MongoTransactionManager transactionManager(MongoDbFactory mongoDbFactory) {
            return new MongoTransactionManager(mongoDbFactory);
        }
    
        @Bean
        public GridFSBucket getGridFSBuckets(MongoDbFactory mongoDbFactory) {
            MongoDatabase db = mongoDbFactory.getDb();
            return GridFSBuckets.create(db);
        }
    
    }

### 七、启动引导类主程序 ###

H:\JDK\jdk-11.0.3\bin\java.exe -XX:TieredStopAtLevel=1 -noverify -Dspring.output.ansi.enabled=always -Dcom.sun.management.jmxremote -Dspring.jmx.enabled=true -Dspring.liveBeansView.mbeanDomain -Dspring.application.admin.enabled=true "-javaagent:H:\JetBrains\IntelliJ IDEA 2019.1.3\lib\idea_rt.jar=57705:H:\JetBrains\IntelliJ IDEA 2019.1.3\bin" -Dfile.encoding=UTF-8 -classpath F:\IdeaProjects\springbootmongodb\target\classes;E:\maven\repository\org\springframework\boot\spring-boot-starter-web\2.1.4.RELEASE\spring-boot-starter-web-2.1.4.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter\2.1.4.RELEASE\spring-boot-starter-2.1.4.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-logging\2.1.4.RELEASE\spring-boot-starter-logging-2.1.4.RELEASE.jar;E:\maven\repository\ch\qos\logback\logback-classic\1.2.3\logback-classic-1.2.3.jar;E:\maven\repository\ch\qos\logback\logback-core\1.2.3\logback-core-1.2.3.jar;E:\maven\repository\org\apache\logging\log4j\log4j-to-slf4j\2.11.2\log4j-to-slf4j-2.11.2.jar;E:\maven\repository\org\apache\logging\log4j\log4j-api\2.11.2\log4j-api-2.11.2.jar;E:\maven\repository\org\slf4j\jul-to-slf4j\1.7.26\jul-to-slf4j-1.7.26.jar;E:\maven\repository\javax\annotation\javax.annotation-api\1.3.2\javax.annotation-api-1.3.2.jar;E:\maven\repository\org\yaml\snakeyaml\1.23\snakeyaml-1.23.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-json\2.1.4.RELEASE\spring-boot-starter-json-2.1.4.RELEASE.jar;E:\maven\repository\com\fasterxml\jackson\core\jackson-databind\2.9.8\jackson-databind-2.9.8.jar;E:\maven\repository\com\fasterxml\jackson\core\jackson-annotations\2.9.0\jackson-annotations-2.9.0.jar;E:\maven\repository\com\fasterxml\jackson\core\jackson-core\2.9.8\jackson-core-2.9.8.jar;E:\maven\repository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.9.8\jackson-datatype-jdk8-2.9.8.jar;E:\maven\repository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.9.8\jackson-datatype-jsr310-2.9.8.jar;E:\maven\repository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.9.8\jackson-module-parameter-names-2.9.8.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-tomcat\2.1.4.RELEASE\spring-boot-starter-tomcat-2.1.4.RELEASE.jar;E:\maven\repository\org\apache\tomcat\embed\tomcat-embed-core\9.0.17\tomcat-embed-core-9.0.17.jar;E:\maven\repository\org\apache\tomcat\embed\tomcat-embed-el\9.0.17\tomcat-embed-el-9.0.17.jar;E:\maven\repository\org\apache\tomcat\embed\tomcat-embed-websocket\9.0.17\tomcat-embed-websocket-9.0.17.jar;E:\maven\repository\org\hibernate\validator\hibernate-validator\6.0.16.Final\hibernate-validator-6.0.16.Final.jar;E:\maven\repository\javax\validation\validation-api\2.0.1.Final\validation-api-2.0.1.Final.jar;E:\maven\repository\org\jboss\logging\jboss-logging\3.3.2.Final\jboss-logging-3.3.2.Final.jar;E:\maven\repository\com\fasterxml\classmate\1.4.0\classmate-1.4.0.jar;E:\maven\repository\org\springframework\spring-web\5.1.6.RELEASE\spring-web-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\spring-beans\5.1.6.RELEASE\spring-beans-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\spring-webmvc\5.1.6.RELEASE\spring-webmvc-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\spring-aop\5.1.6.RELEASE\spring-aop-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\spring-context\5.1.6.RELEASE\spring-context-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\spring-expression\5.1.6.RELEASE\spring-expression-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-data-mongodb\2.1.4.RELEASE\spring-boot-starter-data-mongodb-2.1.4.RELEASE.jar;E:\maven\repository\org\springframework\data\spring-data-mongodb\2.1.6.RELEASE\spring-data-mongodb-2.1.6.RELEASE.jar;E:\maven\repository\org\springframework\spring-tx\5.1.6.RELEASE\spring-tx-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\data\spring-data-commons\2.1.6.RELEASE\spring-data-commons-2.1.6.RELEASE.jar;E:\maven\repository\org\slf4j\slf4j-api\1.7.26\slf4j-api-1.7.26.jar;E:\maven\repository\org\springframework\spring-core\5.1.6.RELEASE\spring-core-5.1.6.RELEASE.jar;E:\maven\repository\org\springframework\spring-jcl\5.1.6.RELEASE\spring-jcl-5.1.6.RELEASE.jar;E:\maven\repository\org\mongodb\mongodb-driver\3.8.2\mongodb-driver-3.8.2.jar;E:\maven\repository\org\mongodb\bson\3.8.2\bson-3.8.2.jar;E:\maven\repository\org\mongodb\mongodb-driver-core\3.8.2\mongodb-driver-core-3.8.2.jar;E:\maven\repository\org\springframework\boot\spring-boot-configuration-processor\2.1.4.RELEASE\spring-boot-configuration-processor-2.1.4.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-devtools\2.1.4.RELEASE\spring-boot-devtools-2.1.4.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot\2.1.4.RELEASE\spring-boot-2.1.4.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-autoconfigure\2.1.4.RELEASE\spring-boot-autoconfigure-2.1.4.RELEASE.jar com.zsx.MongoDBApplication
    
      .   ____          _            __ _ _
     /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
    ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
     \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
      '  |____| .__|_| |_|_| |_\__, | / / / /
     =========|_|==============|___/=/_/_/_/
     :: Spring Boot ::        (v2.1.4.RELEASE)
    
    2019-07-08 21:56:43.290  INFO 7576 --- [  restartedMain] com.zsx.MongoDBApplication               : Starting MongoDBApplication on zsx with PID 7576 (F:\IdeaProjects\springbootmongodb\target\classes started by admin in F:\IdeaProjects\springbootmongodb)
    2019-07-08 21:56:43.293  INFO 7576 --- [  restartedMain] com.zsx.MongoDBApplication               : No active profile set, falling back to default profiles: default
    2019-07-08 21:56:43.515  INFO 7576 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
    2019-07-08 21:56:43.517  INFO 7576 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
    2019-07-08 21:56:44.727  INFO 7576 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data repositories in DEFAULT mode.
    2019-07-08 21:56:44.809  INFO 7576 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 78ms. Found 1 repository interfaces.
    2019-07-08 21:56:45.257  INFO 7576 --- [  restartedMain] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$c3a4430d] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
    2019-07-08 21:56:45.739  INFO 7576 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
    2019-07-08 21:56:45.769  INFO 7576 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
    2019-07-08 21:56:45.769  INFO 7576 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.17]
    2019-07-08 21:56:45.788  INFO 7576 --- [  restartedMain] o.a.catalina.core.AprLifecycleListener   : An older version [1.2.16] of the APR based Apache Tomcat Native library is installed, while Tomcat recommends a minimum version of [1.2.21]
    2019-07-08 21:56:45.789  INFO 7576 --- [  restartedMain] o.a.catalina.core.AprLifecycleListener   : Loaded APR based Apache Tomcat Native library [1.2.16] using APR version [1.6.3].
    2019-07-08 21:56:45.789  INFO 7576 --- [  restartedMain] o.a.catalina.core.AprLifecycleListener   : APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
    2019-07-08 21:56:45.789  INFO 7576 --- [  restartedMain] o.a.catalina.core.AprLifecycleListener   : APR/OpenSSL configuration: useAprConnector [false], useOpenSSL [true]
    2019-07-08 21:56:46.874  INFO 7576 --- [  restartedMain] o.a.catalina.core.AprLifecycleListener   : OpenSSL successfully initialized [OpenSSL 1.0.2m  2 Nov 2017]
    2019-07-08 21:56:47.049  INFO 7576 --- [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
    2019-07-08 21:56:47.049  INFO 7576 --- [  restartedMain] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 3531 ms
    2019-07-08 21:56:47.643  INFO 7576 --- [  restartedMain] org.mongodb.driver.cluster               : Cluster created with settings {hosts=[localhost:27017], mode=SINGLE, requiredClusterType=UNKNOWN, serverSelectionTimeout='30000 ms', maxWaitQueueSize=500}
    2019-07-08 21:56:47.715  INFO 7576 --- [localhost:27017] org.mongodb.driver.connection            : Opened connection [connectionId{localValue:1, serverValue:184}] to localhost:27017
    2019-07-08 21:56:47.725  INFO 7576 --- [localhost:27017] org.mongodb.driver.cluster               : Monitor thread successfully connected to server with description ServerDescription{address=localhost:27017, type=STANDALONE, state=CONNECTED, ok=true, version=ServerVersion{versionList=[4, 0, 10]}, minWireVersion=0, maxWireVersion=7, maxDocumentSize=16777216, logicalSessionTimeoutMinutes=30, roundTripTimeNanos=7966222}
    2019-07-08 21:56:47.916  INFO 7576 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
    2019-07-08 21:56:48.472  INFO 7576 --- [  restartedMain] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
    2019-07-08 21:56:48.693  INFO 7576 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
    2019-07-08 21:56:48.698  INFO 7576 --- [  restartedMain] com.zsx.MongoDBApplication               : Started MongoDBApplication in 6.396 seconds (JVM running for 8.459)

### 八、打开数据库(此处以图片为例) ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pzeDE4MjczMTE3MDAz_size_16_color_FFFFFF_t_70][]

### 九、打开postman ###

**查看请求[http://localhost:8080/api/v1/file/5d234d4efbfab724c88de9da][http_localhost_8080_api_v1_file_5d234d4efbfab724c88de9da]**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pzeDE4MjczMTE3MDAz_size_16_color_FFFFFF_t_70 1][]

### 十、查看 ###

**复制生成的字节数组内容，用在线工具将其还原成图片**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pzeDE4MjczMTE3MDAz_size_16_color_FFFFFF_t_70 2][]

**从以上结果看出，获取图片文件成功**

[springboot_mongodb]: https://blog.csdn.net/zsx18273117003/article/details/94591817
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pzeDE4MjczMTE3MDAz_size_16_color_FFFFFF_t_70]: /images/20211211/213ebfbb3ccb410da693937e5e8aadb9.png
[http_localhost_8080_api_v1_file_5d234d4efbfab724c88de9da]: http://localhost:8080/api/v1/file/5d234d4efbfab724c88de9da
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pzeDE4MjczMTE3MDAz_size_16_color_FFFFFF_t_70 1]: /images/20211211/a7226d611486478fa02c5463f559d06d.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pzeDE4MjczMTE3MDAz_size_16_color_FFFFFF_t_70 2]: /images/20211211/8803076e46814e09b37bbefa01114c4a.png