Could not open JPA EntityManager for transaction; nested exception is java.lang.NullPointerException

F:\java\jdk8\jdk1.8.0_211\bin\java.exe -ea -Didea.test.cyclic.buffer.size=1048576 "-javaagent:D:\软件\IntelliJ IDEA 2019.2.2\lib\idea_rt.jar=7513:D:\软件\IntelliJ IDEA 2019.2.2\bin" -Dfile.encoding=UTF-8 -classpath "D:\软件\IntelliJ IDEA 2019.2.2

HTTP Status 500 - Could not open JDBC Connection for transaction; nested exception is java.lang.NoClassDefFoundError: com/mchange/v2/sql/SqlUtils type Exception report message Could not open JDBC Connection for transaction; nested exception is java.l

使用BoneCP作为连接池,在启动Tomcat报出以下异常: 一月 02, 2016 2:12:17 下午 org.apache.tomcat.util.digester.SetPropertiesRule begin警告: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:mynewdpi' did not find a

type Exception report message Request processing failed; nested exception is java.lang.NullPointerException description The server encountered an internal error that prevented it from fulfilling this request. exception org.springframework.web.util.Ne

本人的继承类引用了 service 层的方法,用的注解方式是@Autowired 该注解如果在容器 tomcat 启动后引用后不会报错,不会报 java.lang.NullPointerException 错误. 初始化时如果想调用数据库的数据,而此时 service 层的类没有实例化,导致 tomcat 启动时报空指针错误. 解决办法: @Componentpublic class MessageResource extends AbstractMessageSource implements

问题:调用的方法在一个接口类中,但我并没有注入那个被调用的类 解决:在UserEntity前加上@Autowired @Controller public class MainController { // 自动装配数据库接口,不需要再写原始的Connection来操作数据库 @Autowired UserRepository userRepository; @RequestMapping(value = "/",method = RequestMethod.GET) public S

严重: StandardWrapper.Throwableorg.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for transaction; nested exception is java.sql.SQLException: Connections could not be acquired from the underlying database!

spring boot 启动报错如下 org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure

spring 调度类初始化失败,分析是jar包冲突,日志如下: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scheduler' defined in file [D:\InstallApplication\apache-tomcat-7.0.23\wtpwebapps\campaign\WEB-INF\classes\spring\applicationConte