Flyway ClassNotFoundException：JavaUtilLogCreator

Question

我正在使用 Flyway 5.2.4 和 OSGI Bundle Activator。我想在 bundle Start() 方法上迁移数据库。这是我的 ActivatorClass：

import org.flywaydb.core.Flyway;
import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceRegistration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class Activator implements BundleActivator {
    private final Logger log = LoggerFactory.getLogger(this.getClass());
    private ServiceRegistration serviceRegistration;

    public void start(BundleContext bundleContext) {
        log.info("Starting...");
        serviceRegistration = bundleContext.registerService(IConnector.class.getName(), new Connector(), null);
        log.info("Started.");

        //FlyWay Section
        Flyway flyway = Flyway.configure().dataSource("jdbc:postgresql://localhost:5432/", "postgres", "12345").load();
        flyway.migrate();
    }

    public void stop(BundleContext bundleContext) {
        log.info("Stopping...");
        serviceRegistration.unregister();
        log.info("Stopped.");
    }

}

如您所见，我使用 slf4j 作为记录器。也许这就是为什么我在部署应用程序后在我的 StackTrace 中收到此错误：

java.lang.Exception: Could not start bundle mvn:internship/db-connector/1.0.0 in feature(s) feature-1.0.0: Activator start error in bundle db-connector [2343].
        at org.apache.karaf.features.internal.FeaturesServiceImpl.startBundle(FeaturesServiceImpl.java:519)[20:org.apache.karaf.features.core:3.0.8]
        at org.apache.karaf.features.internal.FeaturesServiceImpl.installFeatures(FeaturesServiceImpl.java:474)[20:org.apache.karaf.features.core:3.0.8]
        at org.apache.karaf.features.internal.FeaturesServiceImpl.installFeature(FeaturesServiceImpl.java:415)[20:org.apache.karaf.features.core:3.0.8]
        at Proxy683d032e_ad2c_4b9a_98f7_baca7b5564f1.installFeature(Unknown Source)[:]
        at Proxyfff1bf4b_671e_4ff6_bb97_e0dabf9f20e8.installFeature(Unknown Source)[:]
        at org.apache.karaf.kar.internal.KarServiceImpl.installFeatures(KarServiceImpl.java:282)[89:org.apache.karaf.kar.core:3.0.8]
        at org.apache.karaf.kar.internal.KarServiceImpl.install(KarServiceImpl.java:111)[89:org.apache.karaf.kar.core:3.0.8]
        at org.apache.karaf.kar.internal.KarServiceImpl.install(KarServiceImpl.java:93)[89:org.apache.karaf.kar.core:3.0.8]
        at Proxy40d8d25a_37b2_4855_a381_fbb78daa68ce.install(Unknown Source)[:]
        at Proxy068a2f57_120b_4ee8_b953_7c8262bae9a2.install(Unknown Source)[:]
        at org.apache.karaf.deployer.kar.KarArtifactInstaller.update(KarArtifactInstaller.java:62)[91:org.apache.karaf.deployer.kar:3.0.8]
        at Proxy3c143b4c_a2ef_49d0_870b_21a9b5f74704.update(Unknown Source)[:]
        at org.apache.felix.fileinstall.internal.DirectoryWatcher.update(DirectoryWatcher.java:1101)[7:org.apache.felix.fileinstall:3.5.2]
        at org.apache.felix.fileinstall.internal.DirectoryWatcher.update(DirectoryWatcher.java:898)[7:org.apache.felix.fileinstall:3.5.2]
        at org.apache.felix.fileinstall.internal.DirectoryWatcher.doProcess(DirectoryWatcher.java:478)[7:org.apache.felix.fileinstall:3.5.2]
        at org.apache.felix.fileinstall.internal.DirectoryWatcher.process(DirectoryWatcher.java:355)[7:org.apache.felix.fileinstall:3.5.2]
        at org.apache.felix.fileinstall.internal.DirectoryWatcher.run(DirectoryWatcher.java:307)[7:org.apache.felix.fileinstall:3.5.2]
Caused by: org.osgi.framework.BundleException: Activator start error in bundle db-connector [2343].
        at org.apache.felix.framework.Felix.activateBundle(Felix.java:2196)[org.apache.felix.framework-4.2.1.jar:]
        at org.apache.felix.framework.Felix.startBundle(Felix.java:2064)[org.apache.felix.framework-4.2.1.jar:]
        at org.apache.felix.framework.BundleImpl.start(BundleImpl.java:955)[org.apache.felix.framework-4.2.1.jar:]
        at org.apache.felix.framework.BundleImpl.start(BundleImpl.java:942)[org.apache.felix.framework-4.2.1.jar:]
        at org.apache.karaf.features.internal.FeaturesServiceImpl.startBundle(FeaturesServiceImpl.java:516)[20:org.apache.karaf.features.core:3.0.8]
        ... 16 more
Caused by: java.lang.ExceptionInInitializerError
        at org.flywaydb.core.internal.util.FeatureDetector.isSlf4jAvailable(FeatureDetector.java:96)
        at org.flywaydb.core.internal.logging.LogCreatorFactory.getLogCreator(LogCreatorFactory.java:39)
        at org.flywaydb.core.api.logging.LogFactory.getLog(LogFactory.java:78)
        at org.flywaydb.core.internal.util.FeatureDetector.<clinit>(FeatureDetector.java:25)
        at org.flywaydb.core.internal.logging.LogCreatorFactory.getLogCreator(LogCreatorFactory.java:35)
        at org.flywaydb.core.api.logging.LogFactory.getLog(LogFactory.java:78)
        at org.flywaydb.core.Flyway.<clinit>(Flyway.java:86)
        at internship.connectors.postgresConnector.Activator.start(Activator.java:18)
        at org.apache.felix.framework.util.SecureAction.startActivator(SecureAction.java:645)
        at org.apache.felix.framework.Felix.activateBundle(Felix.java:2146)
        ... 20 more
Caused by: org.flywaydb.core.api.FlywayException: Unable to instantiate class org.flywaydb.core.internal.logging.javautil.JavaUtilLogCreator : org.flywaydb.core.internal.logging.javautil.JavaUtilLogCreator
        at org.flywaydb.core.internal.util.ClassUtils.instantiate(ClassUtils.java:63)[2348:org.flywaydb.core:5.2.4]
        at org.flywaydb.core.internal.logging.LogCreatorFactory.getLogCreator(LogCreatorFactory.java:46)[2348:org.flywaydb.core:5.2.4]
        at org.flywaydb.core.api.logging.LogFactory.getLog(LogFactory.java:78)[2348:org.flywaydb.core:5.2.4]
        at org.flywaydb.core.internal.util.ClassUtils.<clinit>(ClassUtils.java:39)[2348:org.flywaydb.core:5.2.4]
        ... 30 more
Caused by: java.lang.ClassNotFoundException: org.flywaydb.core.internal.logging.javautil.JavaUtilLogCreator
        at java.net.URLClassLoader.findClass(Unknown Source)[:1.8.0_212]
        at java.lang.ClassLoader.loadClass(Unknown Source)[:1.8.0_212]
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)[:1.8.0_212]
        at java.lang.ClassLoader.loadClass(Unknown Source)[:1.8.0_212]
        at java.lang.Class.forName0(Native Method)[:1.8.0_212]
        at java.lang.Class.forName(Unknown Source)[:1.8.0_212]
        at org.flywaydb.core.internal.util.ClassUtils.instantiate(ClassUtils.java:61)[2348:org.flywaydb.core:5.2.4]
        ... 33 more

所以，我只是不知道这里出了什么问题，我使用了 Flyway 官方网站上最简单的例子，但得到了这个错误。我已经尝试删除自己的记录器。我认为它可以让 FlyWay 使用它的记录器，但一切都是一样的（同样的错误）。

你能帮帮我吗？

P.S。看起来这个 pull request 与我的问题有某种关联。

Answer 1

事实上，Flyway 似乎在 OSGi 中存在问题。也许你可以给他们一个问题和你的例子。

您的示例的另一个问题是您尝试通过 url 访问数据源。这在 OSGi 中不起作用。原因是这种方式 flyway 必须直接访问数据库驱动程序类。这在 OSGi 中不起作用。

在 OSGi 中，访问数据库的方式是使用 DataSourceFactory，数据库驱动程序将其创建为服务。您可以从这个工厂创建数据源。

由于并非所有数据库驱动程序都提供此服务，因此 pax-jdbc 为所有常见数据库提供工厂。它还允许创建一个数据源，包括来自 OSGi 配置的池。

您在捆绑启动时迁移的方法是一个非常糟糕的主意。激活器中的方法必须 return 快速并且数据库迁移可能需要一段时间。当然，您希望确保在系统中的任何捆绑包访问数据库之前进行迁移。幸运的是，有一种方法可以连接到 DataSource 创建中以执行迁移等操作。

在将 DataSource 提供给任何其他包之前，请参阅 liquibase tutorial which also shows a database migration. It uses the PreHook offered by pax-jdbc which makes sure your migration code 是运行。

Answer 2

我通过在输入 flyway 的迁移代码之前设置自定义 LogFactory 设法避免了这个错误。 this sample commit

中介绍了基本思想

Flyway ClassNotFoundException：JavaUtilLogCreator

Flyway ClassNotFoundException: JavaUtilLogCreator

java

osgi

database-migration

flyway