拋出java.lang.ClassNotFoundException：org.postgresql.Driver春

Question

我的問題：拋出java.lang.ClassNotFoundException：org.postgresql.Driver
我用：春天，Java EE中，Maven的，Tomcat的，PostgreSQL的
鏈接到項目：https://github.com/Dimassss/RecentlyRepository
說明：
要獲得例外嘗試點擊鏈接運行項目之後。
獲取更多信息問我。

例外：

08-Aug-2017 20:29:00.215 INFO [RMI TCP Connection(3)-127.0.0.1] org.apache.catalina.core.ApplicationContext.log No Spring WebApplicationInitializer types detected on classpath 
08-Aug-2017 20:29:00.629 INFO [RMI TCP Connection(3)-127.0.0.1] org.apache.catalina.core.ApplicationContext.log Initializing Spring FrameworkServlet 'mvc-dispatcher' 
08-Aug-2017 20:29:10.787 SEVERE [http-nio-8080-exec-5] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [mvc-dispatcher] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.exception.GenericJDBCException: Could not open connection] with root cause 
java.lang.ClassNotFoundException: ${db.driver} 
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1275) 
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1109) 
    at org.apache.commons.dbcp.BasicDataSource.createConnectionFactory(BasicDataSource.java:1420) 
    at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1371) 
    at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044) 
    at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:139) 
    at org.hibernate.internal.AbstractSessionImpl$NonContextualJdbcConnectionAccess.obtainConnection(AbstractSessionImpl.java:380) 
    at org.hibernate.engine.jdbc.internal.LogicalConnectionImpl.obtainConnection(LogicalConnectionImpl.java:228) 
    at org.hibernate.engine.jdbc.internal.LogicalConnectionImpl.getConnection(LogicalConnectionImpl.java:171) 
    at org.hibernate.internal.SessionImpl.connection(SessionImpl.java:450) 
    at org.springframework.orm.hibernate4.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:429) 
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373) 
    at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:420) 
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:257) 
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95) 
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) 
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207) 
    at com.sun.proxy.$Proxy25.listBooks(Unknown Source) 
    at net.proselyte.bookmanager.controller.BookController.listBooks(BookController.java:27) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:498) 
    at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215) 
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132) 
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) 
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749) 
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689) 
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83) 
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938) 
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870) 
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961) 
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:622) 
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) 
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) 
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:474) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) 
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) 
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624) 
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) 
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783) 
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) 
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:745) 
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1437) 
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) 
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) 
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) 
    at java.lang.Thread.run(Thread.java:745) 

Answer 1

你需要爲你的項目的pom.xml文件中添加下面的依賴，你可以

<dependency> 
    <groupId>postgresql</groupId> 
    <artifactId>postgresql</artifactId> 
    <version>9.1-901-1.jdbc4</version> 
</dependency> 

你也可以從下載JAR以下鏈接

https://jdbc.postgresql.org/download.html

Answer 2

它在我看來，問題是你彈簧不知道application.properties文件。如果您使用的是彈簧啓動，它會自動啓動，但在普通的舊式彈簧中，您必須按照我所知明確添加它。

爲了做到這一點使用PropertyPlaceholderConfigurer作爲this博客帖子描述：

<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> 
    <property name="location"> 
     <value>application.properties</value> 
    </property> 
</bean> 

Answer 3

要解決的項目，我應該在MVC-調度-servlet.xml中寫的一樣在這裏：

<bean class="org.apache.commons.dbcp.BasicDataSource" id="dataSource" destroy-method="close"> 
    <property name="url" value="jdbc:postgresql://localhost:5432/bookmanager"/> 
    <property name="username" value="username"/> 
    <property name="password" value="password"/> 
    <property name="driverClassName" value="org.postgresql.Driver"/> 
</bean> 

它工作，因爲我的項目無法從屬性文件讀取。