在 Spring Boot 中配置数据源答案

【问题标题】：Configure Data Source in Spring boot在 Spring Boot 中配置数据源
【发布时间】：2021-09-24 02:23:56
【问题描述】：

我有一个 Spring Boot 应用程序，

目前使用此配置作为数据源

@PropertySource("file:D:\\Spring Workspace\\test\\dbconfig.properties")
public class DataSourceConfig {
    @Value("db_driverClassName")
    private String className;
    @Value("db_url")
    private String url;
    @Value("db_username")
    private String username;
    @Value("db_userpassword")
    private String password;
    
    @Bean
    public DataSource getDataSource() {
        dataSourceBuilder.driverClassName(className);
        dataSourceBuilder.url(url);
        dataSourceBuilder.username(username);
        dataSourceBuilder.password(password);
        return dataSourceBuilder.build();
    }
}

dbconfig.properties 文件

db_driverClassName="org.postgresql.Driver"
db_url="jdbc:postgresql://localhost:5432/testDB"
db_username="postgres"
db_userpassword="password"

例外

2021-07-15 12:34:21.400 ERROR 5352 --- [           main] com.zaxxer.hikari.HikariConfig           : Failed to load driver class db_driverClassName from HikariConfig class classloader jdk.internal.loader.ClassLoaders$AppClassLoader@368239c8
2021-07-15 12:34:21.403  WARN 5352 --- [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'dataSourceScriptDatabaseInitializer' defined in class path resource [org/springframework/boot/autoconfigure/sql/init/DataSourceInitializationConfiguration.class]: Unsatisfied dependency expressed through method 'dataSourceScriptDatabaseInitializer' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'getDataSource' defined in class path resource [com/myapp/quartz/config/DataSourceConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.sql.DataSource]: Factory method 'getDataSource' threw exception; nested exception is java.lang.RuntimeException: Failed to load driver class db_driverClassName in either of HikariConfig class loader or Thread context classloader
2021-07-15 12:34:21.405  INFO 5352 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2021-07-15 12:34:21.418  INFO 5352 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2021-07-15 12:34:21.437 ERROR 5352 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'dataSourceScriptDatabaseInitializer' defined in class path resource [org/springframework/boot/autoconfigure/sql/init/DataSourceInitializationConfiguration.class]: Unsatisfied dependency expressed through method 'dataSourceScriptDatabaseInitializer' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'getDataSource' defined in class path resource [com/myapp/quartz/config/DataSourceConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.sql.DataSource]: Factory method 'getDataSource' threw exception; nested exception is java.lang.RuntimeException: Failed to load driver class db_driverClassName in either of HikariConfig class loader or Thread context classloader
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:800) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:541) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1334) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:564) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:524) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:322) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.8.jar:5.3.8]
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1154) ~[spring-context-5.3.8.jar:5.3.8]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:908) ~[spring-context-5.3.8.jar:5.3.8]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.8.jar:5.3.8]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.5.2.jar:2.5.2]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754) ~[spring-boot-2.5.2.jar:2.5.2]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:434) ~[spring-boot-2.5.2.jar:2.5.2]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:338) ~[spring-boot-2.5.2.jar:2.5.2]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1343) ~[spring-boot-2.5.2.jar:2.5.2]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1332) ~[spring-boot-2.5.2.jar:2.5.2]
    at com.myapp.quartz.GatewayApplication.main(GatewayApplication.java:17) ~[classes/:na]

我尝试通过手动设置值而不是将其放入文件中，这是可行的，但是当我尝试从文件中获取属性值时，我遇到了这个异常。

【问题讨论】：

标签： java spring-boot spring-data-jpa datasource hikaricp

【解决方案1】：

您需要从属性值中删除引号

db_driverClassName=org.postgresql.Driver
db_url=jdbc:postgresql://localhost:5432/testDB
db_username=postgres
db_userpassword=password

【讨论】：

感谢您的快速回复@user7294900，它开始工作了

【解决方案2】：

这里使用相对路径而不是绝对路径

@PropertySource("file:D:\\Spring Workspace\\test\\dbconfig.properties")

并删除dbconfig.properties file中的双引号

【讨论】：

【解决方案3】：

我想在答案中再补充一点，在提出从@user7294900获得的解决方案后，我仍然因此遇到问题，终于解决了

属性文件中值的映射，我使用了错误的语法

@Value("db_driverClassName")

改为

@Value("${db_driverClassName}")

【讨论】：