【发布时间】：2014-08-20 21:29:41
【问题描述】：
（编辑：我已经为这个问题添加了一个赏金。我找到了一个解决方法（作为答案发布在下面），但我希望有人能解释为什么首先需要解决这个问题。）
我有一个在开发过程中连接到 Derby 数据库的 Spring webapp。这在我第一次运行 web 应用程序时工作正常，但在随后的运行中它在启动过程中失败，并出现“另一个 Derby 实例可能已经启动了数据库”SQLException。
我知道这是因为当我关闭 Tomcat 时与 Derby 的连接没有关闭，即使我希望 Spring 会自动处理它。所以我的问题是，如何正确断开与 Derby 的连接？不仅在手动停止 Tomcat 期间，而且在热部署新的 .war 文件期间？
我想避免使用 Derby 服务器，并且我还使用注释而不是 XML 配置。这是我原来的 PersistConfig 类：
package com.example.spring.config;
import java.beans.PropertyVetoException;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
import javax.sql.DataSource;
import org.apache.derby.jdbc.EmbeddedDataSource;
import org.hibernate.SessionFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.datasource.SimpleDriverDataSource;
import org.springframework.jdbc.datasource.embedded.ConnectionProperties;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseConfigurer;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
import org.springframework.orm.hibernate4.HibernateExceptionTranslator;
import org.springframework.orm.hibernate4.HibernateTransactionManager;
import org.springframework.orm.hibernate4.LocalSessionFactoryBean;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.vendor.Database;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@Configuration
@ComponentScan({"com.example.spring.dao.jpa"})
@EnableTransactionManagement // <-- enable @Transactional annotations for spring @Component and stereotypes
public class PersistConfig{
@Bean
public HibernateExceptionTranslator exceptionTranslator() {
return new HibernateExceptionTranslator();
}
@Bean
public LocalSessionFactoryBean localSessionFactoryBean(DataSource dataSource, JpaVendorAdapter vendorAdapter) {
LocalSessionFactoryBean localSessionFactoryBean = new LocalSessionFactoryBean();
localSessionFactoryBean.setDataSource(dataSource);
localSessionFactoryBean.setPackagesToScan("com.example.one", "com.example.two");
Properties properties = new Properties();
properties.putAll(vendorAdapter.getJpaPropertyMap());
localSessionFactoryBean.setHibernateProperties(properties);
return localSessionFactoryBean;
}
@Bean
public HibernateTransactionManager hibernateTransactionManager(SessionFactory sessionFactory) {
HibernateTransactionManager hibernateTransactionManager = new HibernateTransactionManager(sessionFactory);
return hibernateTransactionManager;
}
@Configuration
public static class DevelopmentConfig{
@Bean
public DataSource dataSource() throws SQLException, PropertyVetoException {
DataSource dataSource = new SimpleDriverDataSource(new org.apache.derby.jdbc.EmbeddedDriver(), "jdbc:derby:C:\\Users\\Kevin\\Desktop\\DerbyDB", "", "");
System.out.println("RETURNING DATASOURCE");
return dataSource;
}
@Bean
JpaVendorAdapter vendorAdapter() {
HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
vendorAdapter.setDatabase(Database.DERBY);
vendorAdapter.setDatabasePlatform("org.hibernate.dialect.DerbyDialect");
vendorAdapter.setGenerateDdl(true);
vendorAdapter.setShowSql(true);
vendorAdapter.getJpaPropertyMap().put("hibernate.hbm2ddl.auto", "update");
vendorAdapter.getJpaPropertyMap().put("hbm2ddl.auto", "update");
return vendorAdapter;
}
}
}
我尝试使用 Runtime.addShutdownHook() 将关闭挂钩添加到整个 JVM，在其中我手动断开与 Derby 数据库的连接，但这似乎从未触发过。
然后我被告知查看 EmbeddedDatabaseConfigurer 接口以添加一个 Spring 关闭回调，我在其中手动关闭数据库连接，这就是我想出的：
package com.example.spring.config;
import java.beans.PropertyVetoException;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
import javax.sql.DataSource;
import org.apache.derby.jdbc.EmbeddedDataSource;
import org.hibernate.SessionFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.datasource.SimpleDriverDataSource;
import org.springframework.jdbc.datasource.embedded.ConnectionProperties;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseConfigurer;
import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
import org.springframework.orm.hibernate4.HibernateExceptionTranslator;
import org.springframework.orm.hibernate4.HibernateTransactionManager;
import org.springframework.orm.hibernate4.LocalSessionFactoryBean;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.vendor.Database;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@Configuration
@ComponentScan({"com.example.spring.dao.jpa"})
@EnableTransactionManagement // <-- enable @Transactional annotations for spring @Component and stereotypes
public class PersistConfig implements EmbeddedDatabaseConfigurer {
@Bean
public HibernateExceptionTranslator exceptionTranslator() {
return new HibernateExceptionTranslator();
}
@Bean
public LocalSessionFactoryBean localSessionFactoryBean(DataSource dataSource, JpaVendorAdapter vendorAdapter) {
LocalSessionFactoryBean localSessionFactoryBean = new LocalSessionFactoryBean();
localSessionFactoryBean.setDataSource(dataSource);
localSessionFactoryBean.setPackagesToScan("com.example.one", "com.example.two");
Properties properties = new Properties();
properties.putAll(vendorAdapter.getJpaPropertyMap());
localSessionFactoryBean.setHibernateProperties(properties);
return localSessionFactoryBean;
}
@Bean
public HibernateTransactionManager hibernateTransactionManager(SessionFactory sessionFactory) {
HibernateTransactionManager hibernateTransactionManager = new HibernateTransactionManager(sessionFactory);
return hibernateTransactionManager;
}
@Configuration
public static class DevelopmentConfig{
@Bean
public DataSource dataSource() throws SQLException, PropertyVetoException {
DataSource dataSource = new SimpleDriverDataSource(new org.apache.derby.jdbc.EmbeddedDriver(), "jdbc:derby:C:\\Users\\Kevin\\Desktop\\DerbyDB", "", "");
System.out.println("RETURNING DATASOURCE");
return dataSource;
}
@Bean
JpaVendorAdapter vendorAdapter() {
HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
vendorAdapter.setDatabase(Database.DERBY);
vendorAdapter.setDatabasePlatform("org.hibernate.dialect.DerbyDialect");
vendorAdapter.setGenerateDdl(true);
vendorAdapter.setShowSql(true);
vendorAdapter.getJpaPropertyMap().put("hibernate.hbm2ddl.auto", "update");
vendorAdapter.getJpaPropertyMap().put("hbm2ddl.auto", "update");
return vendorAdapter;
}
}
@Override
public void configureConnectionProperties(ConnectionProperties properties, String databaseName) {
System.out.println("CONFIGURE");
properties.setDriverClass(org.apache.derby.jdbc.EmbeddedDriver.class);
properties.setUrl("jdbc:derby:C:\\Users\\Kevin\\Desktop\\DerbyDB");
}
@Override
public void shutdown(DataSource ds, String databaseName) {
System.out.println("SHUTTING DOWN");
try {
DriverManager.getConnection("jdbc:derby:C:\\Users\\Kevin\\Desktop\\DerbyDB;shutdown=true");
}
catch (SQLException e) {
e.printStackTrace();
}
}
}
但是，configureConnectionProperties() 函数和 shutdown() 函数似乎都没有被调用。我显然不知道我在做什么，所以任何指针都非常感谢。
【问题讨论】：
-
只有在重新部署应用程序时才会出现问题，还是在以下情况下也会出现问题：1/停止，取消部署，稍等（> 30秒），重新部署和2/停止tomcat，重新启动雄猫？
-
@SergeBallesta 无论我做什么都会发生：我尝试停止 tomcat，从 Tomcat 的 webapp 目录中删除 .war 和目录，然后将新的 .war 文件复制到 webapp 目录中，然后再次启动Tomcat。我还尝试通过复制新的 .war 文件来“热部署”。两者都生成 SQLException。
标签： java spring tomcat spring-mvc derby