Configuration.generateSchemaCreationScript() 在 Hibernate 5 中去了哪里

Question

在 Hibernate 4.x 中，我曾经生成并导出在带注释的实体中定义的模式，如下所示（使用 Spring 在 class 路径上查找带注释的实体）：

Connection connection = 
    DriverManager.getConnection("jdbc:h2:mem:jooq-meta-extensions", "sa", "");

Configuration configuration = new Configuration()
    .setProperty("hibernate.dialect", "org.hibernate.dialect.H2Dialect");

// [...] adding annotated classes to Configuration here...

configuration.generateSchemaCreationScript(
    Dialect.getDialect(configuration.getProperties()));
SchemaExport export = new SchemaExport(configuration, connection);
export.create(true, true);

这在 Hibernate 5.0 中不再有效：

Configuration.generateSchemaCreationScript() 不再存在
SchemaExport(configuration, connection) 构造函数现已弃用

除了：

，我在 migration guide 中没有真正找到任何明显的对这一变化的引用

Quite a few methods have been removed from Configuration

基于一组带注释的实体，使用 Hibernate 5.0 在现有 JDBC 连接上生成和导出数据库 的正确方法是什么？（纯基于 JPA 的解决方案也很好）

（请注意，仅删除对 generateSchemaCreationScript() 的调用似乎可行，但我希望确保正确执行此操作）

Answer 1

新 SchemaExport 初始化的一个示例在 SchemaExportTask 中找到：

final BootstrapServiceRegistry bsr = new BootstrapServiceRegistryBuilder().build();

final MetadataSources metadataSources = new MetadataSources( bsr );
final StandardServiceRegistryBuilder ssrBuilder = new StandardServiceRegistryBuilder( bsr );

if ( configurationFile != null ) {
    ssrBuilder.configure( configurationFile );
}
if ( propertiesFile != null ) {
    ssrBuilder.loadProperties( propertiesFile );
}
ssrBuilder.applySettings( getProject().getProperties() );

for ( String fileName : getFiles() ) {
    if ( fileName.endsWith(".jar") ) {
        metadataSources.addJar( new File( fileName ) );
    }
    else {
        metadataSources.addFile( fileName );
    }
}


final StandardServiceRegistryImpl ssr = (StandardServiceRegistryImpl) ssrBuilder.build();
final MetadataBuilder metadataBuilder = metadataSources.getMetadataBuilder( ssr );

ClassLoaderService classLoaderService = bsr.getService( ClassLoaderService.class );
if ( implicitNamingStrategy != null ) {
    metadataBuilder.applyImplicitNamingStrategy(
            (ImplicitNamingStrategy) classLoaderService.classForName( implicitNamingStrategy ).newInstance()
    );
}
if ( physicalNamingStrategy != null ) {
    metadataBuilder.applyPhysicalNamingStrategy(
            (PhysicalNamingStrategy) classLoaderService.classForName( physicalNamingStrategy ).newInstance()
    );
}

return new SchemaExport( (MetadataImplementor) metadataBuilder.build() )
    .setHaltOnError( haltOnError )
    .setOutputFile( outputFile.getPath() )
    .setDelimiter( delimiter );

当然，您可以根据自己的需要进行定制。

Answer 2

新的 bootstrap API 允许许多自定义，但假设您不需要这些，最短的调用看起来像这样，为服务注册表和所有设置应用默认值：

Metadata metadata = new MetadataSources()
    .addAnnotatedClass( MyEntity.class )
    .build();

new SchemaExport( (MetadataImplementor) metadata )
    .setOutputFile( "my-statements.ddl" )
    .create( Target.NONE );

更新：提供应用配置属性的示例

有几种方法可以为连接URL、方言等注入属性。例如您可以提供一个文件 hibernate.properties 或者您使用根据所需设置定制的服务注册表：

StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
    .applySetting( "hibernate.connection.url", "jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1" )
    .build();

Metadata metadata = new MetadataSources( registry )
    .build();

Answer 3

感谢 and 的回答，我设法通过新配置 API 找到了生成具有以下等效导出逻辑的方法。当然，历史表明这个API会再次崩溃，所以一定要选择合适的版本：

休眠 5.2:

MetadataSources metadata = new MetadataSources(
    new StandardServiceRegistryBuilder()
        .applySetting("hibernate.dialect", "org.hibernate.dialect.H2Dialect")
        .applySetting("javax.persistence.schema-generation-connection", connection)
        .build());

// [...] adding annotated classes to metadata here...
metadata.addAnnotatedClass(...);

SchemaExport export = new SchemaExport();
export.create(EnumSet.of(TargetType.DATABASE), metadata.buildMetadata());

Hibernate 5.2（无警告）：

上面会产生一些讨厌的警告，可以忽略：

Okt 20, 2016 2:57:16 PM org.hibernate.engine.jdbc.connections.internal.ConnectionProviderInitiator initiateService
WARN: HHH000181: No appropriate connection provider encountered, assuming application will be supplying connections
Okt 20, 2016 2:57:16 PM org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator initiateService
WARN: HHH000342: Could not obtain connection to query metadata : The application must supply JDBC connections

... 或者您可以通过将以下 ConnectionProvider 修改到设置中来解决这些问题（我认为不需要这样做）

        .applySetting(AvailableSettings.CONNECTION_PROVIDER, new ConnectionProvider() {
            @Override
            public boolean isUnwrappableAs(Class unwrapType) {
                return false;
            }
            @Override
            public <T> T unwrap(Class<T> unwrapType) {
                return null;
            }
            @Override
            public Connection getConnection() {
                return connection; // Interesting part here
            }
            @Override
            public void closeConnection(Connection conn) throws SQLException {}

            @Override
            public boolean supportsAggressiveRelease() {
                return true;
            }
        })

休眠 5.0:

MetadataSources metadata = new MetadataSources(
    new StandardServiceRegistryBuilder()
        .applySetting("hibernate.dialect", "org.hibernate.dialect.H2Dialect")
        .build());

// [...] adding annotated classes to metadata here...
metadata.addAnnotatedClass(...);

SchemaExport export = new SchemaExport(
    (MetadataImplementor) metadata.buildMetadata(),
    connection // pre-configured Connection here
);
export.create(true, true);

休眠 4：

提醒一下，这在 Hibernate 4 中是如何工作的：

Configuration configuration = new Configuration()
    .setProperty("hibernate.dialect", "org.hibernate.dialect.H2Dialect");

// [...] adding annotated classes to metadata here...
configuration.addAnnotatedClass(...);

configuration.generateSchemaCreationScript(
    Dialect.getDialect(configuration.getProperties()));
SchemaExport export = new SchemaExport(configuration, connection);
export.create(true, true);

Answer 4

万一使用 JPA 2.1+ - 有一种非常简单的内置可能性来生成 ddl。只需设置以下 jpa 属性，就会创建 ddl 文件。使用 spring 引导，可以使用这些特定的配置选项编写一个单独的主 class。

JPA 2.1+

javax.persistence.schema-generation.scripts.action=drop-and-create
javax.persistence.schema-generation.scripts.create-target=create.ddl
javax.persistence.schema-generation.scripts.drop-target=drop.ddl

Spring 使用 JPA 2.1+

启动

schemagenerator.properties（放入资源文件夹）：

spring.jpa.properties.javax.persistence.schema-generation.scripts.action=drop-and-create
spring.jpa.properties.javax.persistence.schema-generation.scripts.create-target=create.ddl
spring.jpa.properties.javax.persistence.schema-generation.scripts.drop-target=drop.ddl
flyway.enabled=false // in case you use flyway for db maintenance

Spring 引导架构生成器：

public class SchemaGenerator {
    public static void main(String[] args) throws Exception {
        SpringApplication.run(Application.class, new String[]{"--spring.config.name=schemagenerator"}).close();
    }
}

Answer 5

我用 hibernate 5.4 以这种方式导出它。9.Final:

import org.hibernate.boot.Metadata;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.hibernate.tool.schema.TargetType;

import java.util.EnumSet;

public class ExportSchema {
    public static void main(String[] args) {
        final StandardServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
                .applySetting("hibernate.dialect", "org.hibernate.dialect.H2Dialect")
                .build();
        final Metadata metadata = new MetadataSources(serviceRegistry)
                .addAnnotatedClass(...)
                .buildMetadata();
        new SchemaExport()
                .setFormat(true)
                .setDelimiter(";")
                .setOutputFile("schema.sql")
                .execute(EnumSet.of(TargetType.SCRIPT), SchemaExport.Action.CREATE, metadata);
    }
}

Configuration.generateSchemaCreationScript() 在 Hibernate 5 中去了哪里

Where did Configuration.generateSchemaCreationScript() go in Hibernate 5

java

configuration

jpa

hbm2ddl

hibernate-5.x

休眠 5.2:

Hibernate 5.2（无警告）：

休眠 5.0:

休眠 4：