java - 带有 Spring Boot 和 ibm JDBC 驱动程序的 ClassNotFoundException

Question

我正在尝试设置一个 spring-boot 应用程序以连接到 IBM i 机器上的 DB2 数据库。我已经向 IBM jdbc 驱动程序 com.ibm.as400.access.AS400JDBCDriver 添加了 Maven 依赖项并添加了 spring.datasource.driver-class-name="com.ibm.as400. access.AS400JDBCDriver" 到 application.properties 文件。

当我运行应用程序时，出现错误 Cannot load driver class: "com.ibm.as400.access.AS400JDBCDriver。错误发生在 ClassUtils.forName org.springframework.boot.autoconfigure.jdbc 中 spring-boot 的 DataSourceProperties 类中的下面一行

private boolean driverClassIsLoadable() {
    try {
        ClassUtils.forName(this.driverClassName, null); <----- Exception happens here.  
        return true;
    }
    catch (UnsupportedClassVersionError ex) {
        // Driver library has been compiled with a later JDK, propagate error
        throw ex;
    }
    catch (Throwable ex) {
        return false;
    }
}

this.driverClassName 等于“com.ibm.as400.access.AS400JDBCDriver”。有趣的是，在我的 main 方法中，我可以使用相同的 driverClassName 调用相同的函数并且没有异常。

@SpringBootApplication
public class MinimumExampleApplication {

public static void main(String[] args) throws ClassNotFoundException, LinkageError {
    ClassUtils.forName("com.ibm.as400.access.AS400JDBCDriver", null); <---- No exception here?
    SpringApplication.run(MinimumExampleApplication.class, args);
  }
}

我的问题是我自己加载能找到驱动，为什么spring-boot找不到驱动？

完整程序

MinimumExample.java

package org.mystuff.annual.meeting.signup;

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

@SpringBootApplication
public class MinimumExampleApplication {

  public static void main(String[] args) throws ClassNotFoundException,    LinkageError {
    ClassUtils.forName("com.ibm.as400.access.AS400JDBCDriver", null);
    SpringApplication.run(MinimumExampleApplication.class, args);
  }
}

application.properties

spring.datasource.driver-class-name="com.ibm.as400.access.AS400JDBCDriver"
spring.datasource.url="jdbc:db2://myserver/myDb"
spring.datasource.dbcp2.initial-size=2
spring.datasource.dbcp2.max-total=5

pom.xml

<?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.mystuff</groupId>
    <artifactId>annual-meeting-signup</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>

    <name>minimum-example</name>
    <description>Playing with data repository</description>

    <parent>
        <groupId>org.mystuff</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.2.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-jdbc</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-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.ibm.as400</groupId>
            <artifactId>jt400</artifactId>
            <version>8</version>
        </dependency>
    </dependencies>

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


</project>

Answer 1

正如@Andy Wilkinson 提到的，问题是由我的 application.properties 文件中的引号引起的。我是这样配置的

spring.datasource.driver-class-name="com.ibm.as400.access.AS400JDBCDriver"
spring.datasource.url="jdbc:db2://myserver/myDb"
spring.datasource.dbcp2.initial-size=2
spring.datasource.dbcp2.max-total=5

如果我改成下面的就可以了

spring.datasource.driver-class-name=com.ibm.as400.access.AS400JDBCDriver
spring.datasource.url=jdbc:db2://myserver/myDb
spring.datasource.dbcp2.initial-size=2
spring.datasource.dbcp2.max-total=5