Question

有人可以帮助我，并想一想为什么下面的代码不生成SQL创建脚本？ Hibernate版本是5.2.9.Final。我尝试了不同的方法，使用了确切的类名，包位置，与现有数据库的连接，但不幸的是，它们中没有一个适合我。我在互联网上找到的所有代码片段都像我的代码片段。

Class<PostgreSQL95Dialect> dialect = PostgreSQL95Dialect.class;

        StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
            .applySetting(Environment.DIALECT, dialect)
            .build();

        MetadataSources metadataSources = new MetadataSources(registry);

        Set<Class<?>> entities = new Reflections("").getTypesAnnotatedWith(Entity.class);
        entities.forEach(e -> metadataSources.addAnnotatedClass(e.getClass()));

        System.out.println(String.format("entities : %d", entities.size()));

        Metadata metadata = metadataSources.buildMetadata();

        new SchemaExport()
            .setFormat(true)
            .setDelimiter(";")
            .setOutputFile(String.format("ddl_%s.sql ", dialect.getSimpleName()))
            .execute(EnumSet.of(TargetType.STDOUT, TargetType.SCRIPT), SchemaExport.Action.BOTH, metadata);

        StandardServiceRegistryBuilder.destroy(registry);

代码执行的结果在

之下

    Apr 27, 2017 7:26:43 PM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {5.2.9.Final}
Apr 27, 2017 7:26:43 PM org.hibernate.cfg.Environment <clinit>
INFO: HHH000206: hibernate.properties not found
entities : 144
Apr 27, 2017 7:26:44 PM org.hibernate.annotations.common.reflection.java.JavaReflectionManager <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {5.0.1.Final}
Apr 27, 2017 7:26:44 PM org.hibernate.engine.jdbc.connections.internal.ConnectionProviderInitiator initiateService
WARN: HHH000181: No appropriate connection provider encountered, assuming application will be supplying connections
Apr 27, 2017 7:26:44 PM org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator initiateService
WARN: HHH000342: Could not obtain connection to query metadata : The application must supply JDBC connections
Apr 27, 2017 7:26:44 PM org.hibernate.dialect.Dialect <init>
INFO: HHH000400: Using dialect: org.hibernate.dialect.PostgreSQL95Dialect
Apr 27, 2017 7:26:44 PM org.hibernate.engine.jdbc.env.internal.LobCreatorBuilderImpl makeLobCreatorBuilder
INFO: HHH000422: Disabling contextual LOB creation as connection was null
Apr 27, 2017 7:26:44 PM org.hibernate.type.BasicTypeRegistry register
INFO: HHH000270: Type registration [java.util.UUID] overrides previous : org.hibernate.type.UUIDBinaryType@5b239d7d
Apr 27, 2017 7:26:44 PM org.hibernate.tool.hbm2ddl.SchemaExport execute
INFO: HHH000227: Running hbm2ddl schema export
Apr 27, 2017 7:26:44 PM org.hibernate.tool.schema.internal.SchemaCreatorImpl applyImportSources
INFO: HHH000476: Executing import script 'org.hibernate.tool.schema.internal.exec.ScriptSourceInputNonExistentImpl@74455848'

如果有任何帮助，我将不胜感激。

Answer 1

hibernate的配置问题再次检查hibernate.refer配置下面的代码示例。

<hibernate-configuration>
    <session-factory name="">
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.default_schema">explorecalifornia</property>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="hibernate.format_sql">true</property>
        <property name="hibernate.connection.password">abc123</property>
    </session-factory>
</hibernate-configuration>

Answer 2

最后，我找到了一个邪恶的根源：）

我创建了一个测试实体并尝试仅为其生成脚本并且代码有效！所以唯一可能出错的地方就是在反思的帮助下获得课程。并且对我感到羞耻，我是多么不留神。而不是写

entities.forEach(e -> metadataSources.addAnnotatedClass(e.getClass()));

我需要这个

entities.forEach(e -> metadataSources.addAnnotatedClass(e));

第一个总是给出

class java.lang.Class

Hibernate SchemaExport不生成sql脚本

2 个答案: