Spring Boot 中的 PostgreSQL 失败。

Question

我有一个新的Spring Boot应用程序，我正在尝试将其连接到我的本地PostgreSQL实例，但是出现了驱动程序故障。我已经设置了一个基本的驱动程序类，如下所示：

package com.rainydaymatt.lfgenie.lfgenieapi;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class LfgenieApiApplication {

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

为了方便起见，我决定暂不使用.yml配置文件而是采用默认的application.properties文件，并利用我所能找到的关于Spring Boot和PSQL的资料把它们拼凑在一起：

spring.datasource.url=jdbc:postgresql://localhost:15432/harpm
spring.datasource.username=admin
spring.datasource.driver-class-name=org.postgresql.Driver

然后，像这样向Initializr构建的pom添加了一个持久的PostgreSQL实例的依赖项：

<groupId>com.rainydaymatt.lfgenie</groupId>
<artifactId>lfgenie-api</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>

<name>lfgenie-api</name>
<description>Demo project for Spring Boot</description>

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.9.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>

    <dependency>
        <groupId>postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <version>9.1-901.jdbc4</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

我遇到了这些失败跟踪信息，看起来是由于缺少或无法访问驱动程序引起的：

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Tomcat.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: org.postgresql.Driver
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:749) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:189) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1193) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1095) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:372) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1173) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1067) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1080) ~[spring-context-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:857) ~[spring-context-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:693) [spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:360) [spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) [spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1118) [spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1107) [spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
at com.rainydaymatt.lfgenie.lfgenieapi.LfgenieApiApplication.main(LfgenieApiApplication.java:10) [classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_92]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_92]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_92]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_92]
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147) [idea_rt.jar:na]

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Tomcat.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: org.postgresql.Driver
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:599) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1173) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1067) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:835) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
... 33 common frames omitted

- rainydaymatt

---

首先，Boot将管理您的驱动程序版本（因此只需删除“version”标记），并且对于实现SPI的任何内容，您不需要指定“driver-class”（Postgres会自动处理）。尝试删除它们并查看是否有效。 - chrylis -cautiouslyoptimistic-

我最初就是这样做的。但是它再次失败，显示以下错误：2017-12-15 17:27:25.395 ERROR 94727 --- [ main] o.a.tomcat.jdbc.pool.ConnectionPool : 无法创建池的初始连接。java.sql.SQLException: 无法从ClassLoader:sun.misc.Launcher$AppClassLoader@6d311334;ClassLoader:sun.misc.Launcher$AppClassLoader@6d311334加载类org.postgresql.Driver。 - rainydaymatt

Answer 1

这是关于您的Postgres驱动程序的问题。尝试使用其它驱动程序或检查本地Maven资源库。或者您可以使用以下驱动程序：

<dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <version>9.4.1208</version>
    </dependency>

- Den B

---

如果第一次不起作用，尝试使用相同的依赖项，但不指定版本，像这样：<dependency>     <groupId>org.postgresql</groupId>     <artifactId>postgresql</artifactId>   </dependency> - BugsForBreakfast

Answer 2

问题通过以下配置和版本解决：

SpringBoot: 2.4.0 Postgres: 9

<dependency>
 <groupId>org.postgresql</groupId>
 <artifactId>postgresql</artifactId>
</dependency>

application.properties

spring.cloud.gcp.sql.enabled=false
spring.datasource.url=jdbc:postgresql://localhost:5433/postgres
spring.datasource.username=postgres
spring.datasource.password=postgres
spring.jpa.properties.hibernate.default_schema=public

spring.datasource.hikari.connectionTimeout=20000
spring.datasource.hikari.maximumPoolSize=5

- Alan Hernandez

Answer 3

以下配置对我有效：

#==== connect to postgreSQL ======#
spring.jpa.hibernate.ddl-auto=create-drop
spring.datasource.url=jdbc:postgresql://localhost:5432/rs_ecommerce
spring.datasource.username=postgres
spring.datasource.password=password
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect

# Disable feature detection by this undocumented parameter. Check the org.hibernate.engine.jdbc.internal.JdbcServiceImpl.configure method for more details.
spring.jpa.properties.hibernate.temp.use_jdbc_metadata_defaults=false

# Because detection is disabled you have to set correct dialect by hand.
spring.jpa.database-platform=org.hibernate.dialect.PostgreSQL9Dialect

# seems like we don't need to put the below driver properties in application.properties file for latest version of postgreSQL.

spring.datasource.driver-class-name=org.postgresql.Driver 

Details: https://jdbc.postgresql.org/documentation/head/load.html

- mahesh kumar

Answer 4

从datasource-url中删除driver-class名称。Spring将从该url中推导出该名称。您应该拥有postgresql的maven依赖项。

- KUNWAR RATHORE

Answer 5

更新以下内容：- pom.xml

 <dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <scope>runtime</scope>
    </dependency>

Application.properties

 spring.datasource.url=jdbc:postgresql://localhost:5432/db_name
 spring.datasource.username=username
 spring.datasource.password=password
 spring.jpa.hibernate.ddl-auto=update
 spring.datasource.driverClassName=org.postgresql.Driver
  spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect

- ujjwal dixit

Answer 6

如果您在 pom.xml 中使用了 PostgreSQL 的依赖项

<dependency>
    <groupId>postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <version>9.1-901.jdbc4</version>
</dependency>

您 不需要 在 application.properties 中添加驱动程序，因此请删除

spring.datasource.driver-class-name=org.postgresql.Driver

它应该可以工作。另外，不要忘记添加密码属性。

spring.datasource.password=your-db-password

- Jimmy Salazar

Answer 7

如果您正在使用Gradle，请在build.gradle文件中添加以下行：

implementation 'org.postgresql:postgresql:42.5.0'

- arnav

Answer 8

       <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>


#==== connect to postgreSQL ======#
spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:postgresql://localhost:5432/schooldb
spring.datasource.username=postgres
spring.datasource.password=postgres
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect

# Disable feature detection by this undocumented parameter. Check the org.hibernate.engine.jdbc.internal.JdbcServiceImpl.configure method for more details.
spring.jpa.properties.hibernate.temp.use_jdbc_metadata_defaults=false

# Because detection is disabled you have to set correct dialect by hand.
spring.jpa.database-platform=org.hibernate.dialect.PostgreSQL9Dialect

- Ganesh Giri

Answer 9

从Spring Boot应用程序的application.properties中删除以下内容。

#spring.datasource.driver-class-name=org.postgresql.Driver

这应该有助于解决问题。

- Syed Aaqib Hussain