如何在 jBPM 默认应用程序中从 H2 数据库切换到 Postgres？

Question

我需要在https://start.jbpm.org 中生成的默认 jBpm 应用程序中从 H2 数据库切换到 Postgres。 我尝试使用给定的application-postgres.propreties更改属性文件，保存文件，然后运行mvn clean install -U启动应用程序.\\launch.bat clean install 。 它返回此异常。 如果我错了，请纠正我，但这意味着应用程序无法创建数据库，即使我将其设置为更新模式。

        at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:798) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:539) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1338) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1108) ~[spring-context-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:868) ~[spring-context-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.2.RELEASE.jar!/:2.2.2.RELEASE]
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.2.RELEASE.jar!/:2.2.2.RELEASE]
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.2.RELEASE.jar!/:2.2.2.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.2.RELEASE.jar!/:2.2.2.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.2.RELEASE.jar!/:2.2.2.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.2.RELEASE.jar!/:2.2.2.RELEASE]
        at com.company.service.Application.main(Application.java:10) ~[classes!/:1.0-SNAPSHOT]
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
        at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
        at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48) ~[business-application-service-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:87) ~[business-application-service-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:51) ~[business-application-service-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
        at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:52) ~[business-application-service-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/jbpm/springboot/datasources/JBPMDataSourceAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.sql.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Unable to create XADataSource instance from 'org.postgresql.xa.PGXADataSource'
        at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:656) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:484) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1338) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1287) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1207) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:885) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:789) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        ... 27 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.sql.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Unable to create XADataSource instance from 'org.postgresql.xa.PGXADataSource'
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        ... 41 common frames omitted
Caused by: java.lang.IllegalStateException: Unable to create XADataSource instance from 'org.postgresql.xa.PGXADataSource'
        at org.jbpm.springboot.datasources.JBPMDataSourceAutoConfiguration.createXaDataSourceInstance(JBPMDataSourceAutoConfiguration.java:139) ~[jbpm-spring-boot-data-sources-7.33.0.Final.jar!/:7.33.0.Final]
        at org.jbpm.springboot.datasources.JBPMDataSourceAutoConfiguration.createXaDataSource(JBPMDataSourceAutoConfiguration.java:126) ~[jbpm-spring-boot-data-sources-7.33.0.Final.jar!/:7.33.0.Final]
        at org.jbpm.springboot.datasources.JBPMDataSourceAutoConfiguration.dataSource(JBPMDataSourceAutoConfiguration.java:68) ~[jbpm-spring-boot-data-sources-7.33.0.Final.jar!/:7.33.0.Final]
        at org.jbpm.springboot.datasources.JBPMDataSourceAutoConfiguration$$EnhancerBySpringCGLIB$$d82c7bfc.CGLIB$dataSource$0(<generated>) ~[jbpm-spring-boot-data-sources-7.33.0.Final.jar!/:7.33.0.Final]
        at org.jbpm.springboot.datasources.JBPMDataSourceAutoConfiguration$$EnhancerBySpringCGLIB$$d82c7bfc$$FastClassBySpringCGLIB$$3cf69439.invoke(<generated>) ~[jbpm-spring-boot-data-sources-7.33.0.Final.jar!/:7.33.0.Final]
        at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244) ~[spring-core-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:363) ~[spring-context-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.jbpm.springboot.datasources.JBPMDataSourceAutoConfiguration$$EnhancerBySpringCGLIB$$d82c7bfc.dataSource(<generated>) ~[jbpm-spring-boot-data-sources-7.33.0.Final.jar!/:7.33.0.Final]
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
        at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        ... 42 common frames omitted
Caused by: java.lang.ClassNotFoundException: org.postgresql.xa.PGXADataSource
        at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:471) ~[na:na]
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:588) ~[na:na]
        at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:92) ~[business-application-service-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ~[na:na]
        at java.base/java.lang.Class.forName0(Native Method) ~[na:na]
        at java.base/java.lang.Class.forName(Class.java:398) ~[na:na]
        at org.springframework.util.ClassUtils.forName(ClassUtils.java:277) ~[spring-core-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.jbpm.springboot.datasources.JBPMDataSourceAutoConfiguration.createXaDataSourceInstance(JBPMDataSourceAutoConfiguration.java:133) ~[jbpm-spring-boot-data-sources-7.33.0.Final.jar!/:7.33.0.Final]
        ... 54 common frames omitted ```

Answer 1

堆栈跟踪中的这一行表明您在应用程序中缺少 Postgres jdbc 驱动程序。

如果您密切关注 business-application-service 文件夹中的 pom.xml 文件，则只有在您激活 postgres 配置文件时才会加载驱动程序。

由于您已经更改了属性文件，因此您可能只在启动应用程序时缺少-P postgres参数。

它应该是这样的

.\launch.bat clean install -P postgres