使用Hibernate4/JPA 2.1在MAVEN版本中生成DDL脚本

Question

似乎hibernate3-maven-plugin用于生成DDL创建/删除脚本的Hibernate 4.3版本与更新版本(使用JPA 2.1)不再兼容.

我使用这个插件配置:

            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>hibernate3-maven-plugin</artifactId>
                <version>3.0</version>
                <executions>
                    <execution>
                        <id>generate-sql-schema</id>
                        <phase>process-sources</phase>
                        <goals>
                            <goal>hbm2ddl</goal>
                        </goals>
                        <configuration>
                            <hibernatetool>
                                <jpaconfiguration persistenceunit="${persistenceUnitName}" />
                                <hbm2ddl update="true" create="true" export="false"
                                    outputfilename="src/main/sql/schema.sql" format="true"
                                    console="true" />
                            </hibernatetool>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

但是我收到以下错误:

[ERROR] Failed to execute goal org.codehaus.mojo:hibernate3-maven-plugin:3.0:hbm2ddl (generate-sql-schema) on project my-project: There was an error creating the AntRun task.
An Ant BuildException has occured: java.lang.NoClassDefFoundError: org/hibernate/util/ReflectHelper: org.hibernate.util.ReflectHelper -> [Help 1]

此类迁移到新包: org.hibernate.internal.util.ReflectHelper

但是我发现没有明确的方法可以在MAVEN版本中继续生成DDL创建脚本.

没有hibernate4-maven-plugin或任何其他官方方式来做到这一点.

所以呢 ？这不是一个应该支持的主要功能吗？怎么做 ？

Answer 1

由于Hibernate 4.3+现在实现JPA 2.1适当的方法来生成DDL脚本是使用下面的一组JPA 2.1特性:

<property name="javax.persistence.schema-generation.scripts.action" value="create"/>
<property name="javax.persistence.schema-generation.create-source" value="metadata"/>
<property name="javax.persistence.schema-generation.scripts.create-target" value="target/jpa/sql/create-schema.sql"/>

可以在此处找到JPA 2.1中其他属性和模式生成上下文的精彩摘要:https: //blogs.oracle.com/arungupta/entry/jpa_2_1_schema_g​​eneration

官方JPA 2.1规范在这里:https: //jcp.org/aboutJava/communityprocess/final/jsr338/index.html

由于这将在运行时生成,您可能希望在构建时执行此DDL生成.

以下是以编程方式生成此脚本的JPA 2.1方法:

import java.io.IOException;
import java.util.Properties;

import javax.persistence.Persistence;

import org.hibernate.jpa.AvailableSettings;

public class JpaSchemaExport {

    public static void main(String[] args) throws IOException {
        execute(args[0], args[1]);
        System.exit(0);
    }

    public static void execute(String persistenceUnitName, String destination) {
        System.out.println("Generating DDL create script to : " + destination);

        final Properties persistenceProperties = new Properties();

        // XXX force persistence properties : remove database target
        persistenceProperties.setProperty(org.hibernate.cfg.AvailableSettings.HBM2DDL_AUTO, "");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_DATABASE_ACTION, "none");

        // XXX force persistence properties : define create script target from metadata to destination
        // persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_CREATE_SCHEMAS, "true");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_SCRIPTS_ACTION, "create");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_CREATE_SOURCE, "metadata");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_SCRIPTS_CREATE_TARGET, destination);

        Persistence.generateSchema(persistenceUnitName, persistenceProperties);
    }

}

你可以看到它非常简单!

现在你可以在AntTask或MAVEN这样的构建中使用它(对于MAVEN):

<plugin>
    <artifactId>maven-antrun-plugin</artifactId>
    <version>1.7</version>
    <executions>
        <execution>
            <id>generate-ddl-create</id>
            <phase>process-classes</phase>
            <goals>
                <goal>run</goal>
            </goals>
            <configuration>
                <target>
                    <!-- ANT Task definition -->
                    <java classname="com.orange.tools.jpa.JpaSchemaExport"
                        fork="true" failonerror="true">
                        <arg value="${persistenceUnitName}" />
                        <arg value="target/jpa/sql/schema-create.sql" />
                        <!-- reference to the passed-in classpath reference -->
                        <classpath refid="maven.compile.classpath" />
                    </java>
                </target>
            </configuration>

        </execution>
    </executions>
</plugin>

请注意,官方的hibernate-maven-plugin也可能或可能不会以某种方式执行此操作:

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-maven-plugin</artifactId>
    <version>4.3.1.Final</version>
</dependency>

请享用 !:)