我正在尝试使用带有spring框架的嵌入式数据库derby。我可以插入数据并阅读它。除了数据库不存在的一件事之外，一切都很好。当我关闭应用程序并再次运行它时，数据不存在。我猜测数据库是再次创建的，但不知道为什么。
我的代码：
@Configuration
@ComponentScan
@EnableAutoConfiguration
public class MainClass
{
@Bean
public DataSource dataSource()
{
// no need shutdown, EmbeddedDatabaseFactoryBean will take care of this
EmbeddedDatabaseBuilder builder = new EmbeddedDatabaseBuilder();
EmbeddedDatabase db = builder
.setType(EmbeddedDatabaseType.DERBY) //.HSQL, .H2 or .DERBY
.setName("some-db")
.addScript("/create-db.sql")
.build();
return db;
}
@Bean
public DataSourceTransactionManager transactionManager(DataSource dataSource)
{
DataSourceTransactionManager d = new DataSourceTransactionManager(dataSource);
return d;
}
public static void main(String[] args)
{
ConfigurableApplicationContext context = new SpringApplicationBuilder(MainClass.class).headless(false).run(args);
MainFrame.mf = context.getBean(MainFrame.class);
MainFrame.mf.setVisible(true);
UserService userService = new UserService();
if(userService.isSignedIn())
{
MainFrame.mf.loggedIn();
}
else
{
MainFrame.mf.loggedOut();
}
}
}
按弹簧输出日志
2017-09-17 20:41:53.461 INFO 3516 --- [ main] com.some.MainClass : Starting MainClass on maker with PID 3516 (C:\..\NetbeansProjects\..\target\classes started by verma in C:\..\NetbeansProjects\proj)
2017-09-17 20:41:53.469 INFO 3516 --- [ main] com.some.MainClass : No active profile set, falling back to default profiles: default
2017-09-17 20:41:53.571 INFO 3516 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@2df32bf7: startup date [Sun Sep 17 20:41:53 IST 2017]; root of context hierarchy
2017-09-17 20:41:56.974 INFO 3516 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-09-17 20:41:57.007 INFO 3516 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2017-09-17 20:41:57.010 INFO 3516 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.16
2017-09-17 20:41:57.278 INFO 3516 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2017-09-17 20:41:57.279 INFO 3516 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 3714 ms
2017-09-17 20:41:57.606 INFO 3516 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2017-09-17 20:41:57.616 INFO 3516 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-09-17 20:41:57.618 INFO 3516 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-09-17 20:41:57.618 INFO 3516 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-09-17 20:41:57.619 INFO 3516 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2017-09-17 20:41:58.028 INFO 3516 --- [ main] o.s.j.d.e.EmbeddedDatabaseFactory : Starting embedded database: url='jdbc:derby:memory:some-db;create=true', username='sa'
2017-09-17 20:41:58.883 INFO 3516 --- [ main] o.s.jdbc.datasource.init.ScriptUtils : Executing SQL script from class path resource [create-db.sql]
2017-09-17 20:41:59.248 INFO 3516 --- [ main] o.s.jdbc.datasource.init.ScriptUtils : Executed SQL script from class path resource [create-db.sql] in 365 ms.
2017-09-17 20:42:00.907 INFO 3516 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@2df32bf7: startup date [Sun Sep 17 20:41:53 IST 2017]; root of context hierarchy
2017-09-17 20:42:01.052 INFO 3516 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/login],methods=[POST]}" onto java.util.Map com.some.connection.ConnectionController.login(java.lang.String)
2017-09-17 20:42:01.055 INFO 3516 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/logout],methods=[POST]}" onto org.springframework.http.ResponseEntity com.some.connection.ConnectionController.logout(java.lang.String)
2017-09-17 20:42:01.062 INFO 3516 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-09-17 20:42:01.063 INFO 3516 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-09-17 20:42:01.153 INFO 3516 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-09-17 20:42:01.155 INFO 3516 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-09-17 20:42:01.250 INFO 3516 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-09-17 20:42:01.717 INFO 3516 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2017-09-17 20:42:01.829 INFO 3516 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-09-17 20:42:01.840 INFO 3516 --- [ main] com.some.MainClass : Started MainClass in 9.034 seconds (JVM running for 9.794)
2017-09-17 20:42:06.305 INFO 3516 --- [ Thread-6] ationConfigEmbeddedWebApplicationContext : Closing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@2df32bf7: startup date [Sun Sep 17 20:41:53 IST 2017]; root of context hierarchy
2017-09-17 20:42:06.314 INFO 3516 --- [ Thread-6] o.s.j.e.a.AnnotationMBeanExporter : Unregistering JMX-exposed beans on shutdown
2017-09-17 20:42:06.348 INFO 3516 --- [ Thread-6] o.s.j.d.e.EmbeddedDatabaseFactory : Shutting down embedded database: url='jdbc:derby:memory:some-db;create=true'
create-db.sql内容
CREATE TABLE table_connection
(
id BIGINT PRIMARY KEY GENERATED ALWAYS AS IDENTITY (START WITH 1, INCREMENT BY 1),
ip VARCHAR(50) UNIQUE,
sessionId VARCHAR(50) DEFAULT NULL
);
解： 接受的答案指向正确的方向，但错误是some-db; create = true无法启动。然后我看了一下Netbeans IDE如何创建derby连接。问题是create = true，我认为它不应该与url一起发送，而是使用以下代码中显示的属性：
@Bean
public DataSource dataSource()
{
DriverManagerDataSource dm = new DriverManagerDataSource("jdbc:derby:some-db", "root", "root");
Properties properties = new Properties();
properties.setProperty("create", "true");
dm.setConnectionProperties(properties);
dm.setSchema("APP");
dm.setDriverClassName("org.apache.derby.jdbc.EmbeddedDriver");
return dm;
}
@Bean(name="Application.dataSourceInitializer")
public DataSourceInitializer dataSourceInitializer(DataSource dataSource)
{
final DataSourceInitializer initializer = new DataSourceInitializer();
initializer.setDataSource(dataSource);
try
{
JdbcTemplate jdbc = new JdbcTemplate(dataSource);
jdbc.queryForList("SELECT id FROM table_connection");
}
catch(Exception e)
{
initializer.setDatabasePopulator(databasePopulator());
}
return initializer;
}
@Value("classpath:create-db.sql")
private Resource schemaScript;
private DatabasePopulator databasePopulator()
{
final ResourceDatabasePopulator populator = new ResourceDatabasePopulator();
populator.addScript(schemaScript);
return populator;
}
如果表已经存在，则脚本create-db.sql可能会出错，因为derby中没有IF EXISTS，所以将它包装在try-catch中。
Bean datasourceInitializer明确命名为“Application.dataSourceInitializer”，因为spring auto-configuration倾向于覆盖它。检查here.
答案 0 :(得分：0)
这是您问题的核心：jdbc:derby:memory:some-db;create=true
当您在Derby JDBC Connection URL中说“memory”时，您明确告诉Derby创建一个非持久数据库。
如果从JDBC Connectino URL中删除'memory：'，Derby将在硬盘的'some-db'目录中创建一个持久，持久的数据库。