Eclipselink 2.5 使用 Maven 生成元模型

Question

我想知道如何使用 Maven 和 Eclipselink 2.5 生成静态元模型。在运行 Eclipselink 2.4 时，将此行添加到 pom.xml 可以正常工作。

// Generate meta model for eclipselink 2.4 (does not work for 2.5)
    <plugin>
                    <groupId>org.bsc.maven</groupId>
                    <artifactId>maven-processor-plugin</artifactId>
                    <version>1.3.1</version>
                    <executions>
                        <execution>
                            <id>process</id>
                            <goals>
                                <goal>process</goal>
                            </goals>
                            <phase>generate-sources</phase>
                            <configuration>
                                <compilerArguments>-Aeclipselink.persistencexml=src/main/resources/META-INF/persistence.xml</compilerArguments>
                                <processors>
                                    <processor>org.eclipse.persistence.internal.jpa.modelgen.CanonicalModelProcessor</processor>
                                </processors>
                                <outputDirectory>${project.build.directory}/generated-sources/meta-model</outputDirectory>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>

但似乎自 2.4 以来发生了一些变化，因为我收到以下错误：

[INFO] javac option: -proc:only
[INFO] javac option: -Aeclipselink.persistencexml=src/main/resources/META-INF/persistence.xml
[INFO] javac option: -processor
[INFO] javac option: org.eclipse.persistence.internal.jpa.modelgen.CanonicalModelProcessor
[INFO] javac option: -s
[INFO] javac option: /home/asdf/target/generated-sources/meta-model
[INFO] diagnostic error: Annotation processor 'org.eclipse.persistence.internal.jpa.modelgen.CanonicalModelProcessor' not found
[INFO] diagnostic warning: Annotation processing without compilation requested but no processors were found.
[ERROR] execute error
java.lang.Exception: error during compilation
    at org.bsc.maven.plugin.processor.AbstractAnnotationProcessorMojo.executeWithExceptionsHandled(AbstractAnnotationProcessorMojo.java:183)
    at org.bsc.maven.plugin.processor.AbstractAnnotationProcessorMojo.execute(AbstractAnnotationProcessorMojo.java:96)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:84)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)

你们能帮帮我吗？ =)

B.R

Answer 1

看来他们已经将 CanonicalModelProcessor 类移到了它自己的 Maven 工件中：

<dependency>
  <groupId>org.eclipse.persistence</groupId>
  <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
  <version>2.5.0</version>
</dependency>

以下 maven-processor-plugin 配置适用于我：

        <plugin>
            <groupId>org.bsc.maven</groupId>
            <artifactId>maven-processor-plugin</artifactId>
            <version>2.2.4</version>
            <executions>
                <execution>
                    <id>eclipselink-jpa-metamodel</id>
                    <goals>
                        <goal>process</goal>
                    </goals>
                    <phase>generate-sources</phase>
                    <configuration>
                        <processors>
                            <processor>org.eclipse.persistence.internal.jpa.modelgen.CanonicalModelProcessor</processor>
                        </processors>
                        <outputDirectory>${project.build.directory}/generated-sources/meta-model</outputDirectory>
                    </configuration>
                </execution>
            </executions>
            <dependencies>
                <dependency>
                    <groupId>org.eclipse.persistence</groupId>
                    <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
                    <version>2.5.0</version>
                    <scope>provided</scope>
                </dependency>
            </dependencies>
        </plugin>

非常重要的说明：只有在持久化单元中声明了实体时才会生成元模型。它不适用于已发现的实体。

Answer 2

对我来说，使用 org.apache.maven.plugins 中的 maven-compiler-plugin 在使用除 mvn clean install 之外的其他命令时会导致 MojoFailureException。

使用 org.eclipse.persistence.jpa.modelgen.processor 2.6.0测试的解决方案。

这两种情况的配置非常相似。

我对@9​​87654327@ 的主要问题是正确配置compilerArguments 部分。这就是为什么我在下面发布（两个）解决方案。

文档可用：HERE。

---

解决方案使用 maven-compiler-plugin from org.bsc.maven

对我来说这个效果更好

<plugin>
    <groupId>org.bsc.maven</groupId>
    <artifactId>maven-processor-plugin</artifactId>
    <executions>
        <execution>
            <id>eclipselink-jpa-metamodel</id>
            <goals>
                <goal>process</goal>
            </goals>
            <configuration>
                <compilerArguments>
                    -Aeclipselink.persistencexml=${basedir}/src/main/resources/META-INF/persistence.xml
                </compilerArguments>
                <processors>
                    <processor>org.eclipse.persistence.internal.jpa.modelgen.CanonicalModelProcessor
                    </processor>
                </processors>
            </configuration>
        </execution>
    </executions>
    <dependencies>
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
            <version>${eclipselink.version}</version>
            <scope>compile</scope>
        </dependency>
    </dependencies>
</plugin>

---

解决方案使用 maven-compiler-plugin from org.apache.maven.plugins

<dependency>
    <groupId>org.eclipse.persistence</groupId>
    <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
    <version>${eclipselink.version}</version>
    <scope>compile</scope>
</dependency>

...

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <configuration>
        <compilerArgs>
            <arg>-Aeclipselink.persistencexml=src/main/resources/META-INF/persistence.xml</arg>
        </compilerArgs>
    </configuration>
</plugin>

Answer 3

为了使配置更简单，我建议您测试：https://github.com/ethlo/eclipselink-maven-plugin。您甚至不需要保留更新的persistence.xml 文件。

<plugin>
<groupId>com.ethlo.persistence.tools</groupId>
<artifactId>eclipselink-maven-plugin</artifactId>
<version>[version]</version>
<executions>
    <execution>
        <id>weave</id>
        <phase>process-classes</phase>
        <goals>
            <goal>weave</goal>
        </goals>
    </execution>
    <execution>
        <id>modelgen</id>
        <phase>generate-sources</phase>
        <goals>
            <goal>modelgen</goal>
        </goals>
    </execution>
</executions>
</plugin>

注意：我是插件的作者。

Answer 4

您可能会收到以下错误：

java.lang.RuntimeException: java.lang.SecurityException: class "org.eclipse.persistence.internal.jpa.modelgen.CanonicalModelProperties"'s signer information does not match signer information of other classes in the same package

由于未解决的错误compilation is broken, modelgen jar is signed in maven repository，现在必须将版本设置为2.5.0-SNAPSHOT。

Answer 5

2017 年更新：

这个问题的主要答案现在已经过时了。 您现在需要执行以下步骤才能使其正常工作。

1) 导入需要的依赖：

<!-- https://mvnrepository.com/artifact/org.eclipse.persistence/org.eclipse.persistence.jpa.modelgen.processor -->
<dependency>
    <groupId>org.eclipse.persistence</groupId>
    <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
    <version>2.5.2</version>
    <scope>compile</scope>
</dependency>

2) 指定 persistence.xml 位置（这是 EL 错误的一种解决方法。请注意，您的路径可能与本示例中指定的路径不同）：

<build>
  <pluginManagement>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.5.1</version>
            <executions>
                <execution>
                    <id>default-compile</id>
                    <phase>compile</phase>
                    <goals>
                        <goal>compile</goal>
                    </goals>
                </execution>
                [...]
            </executions>
            <configuration>
                <source>1.7</source>
                <target>1.7</target>
                <compilerArgs>
                    <arg>-Aeclipselink.persistencexml=src/main/resources/META-INF/persistence.xml</arg>
                </compilerArgs>
            </configuration>
    </plugins>
    [...]
  </pluginManagement>
  [...]
</build>

3) 最后参考以下项目以使用 Maven 的新 Lifecycle Mappings 触发执行： Usage of maven Build Helper Maven Plugin

Answer 6

这是我用的

<dependency>
        <groupId>org.eclipse.persistence</groupId>
        <artifactId>javax.persistence</artifactId>
        <version>2.1.0</version>
        <scope>provided</scope>
    </dependency>

    <dependency>
        <groupId>org.eclipse.persistence</groupId>
        <artifactId>eclipselink</artifactId>
        <version>2.5.1</version>
        <scope>provided</scope>
    </dependency>

    <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
            <version>2.5.1</version>
            <scope>provided</scope>
        </dependency>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.1</version>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
                <compilerArguments>
                    <endorseddirs>${endorsed.dir}</endorseddirs>
                </compilerArguments>
            </configuration>
            <executions>
                <execution>
                    <id>generate-entity-metamodel</id>
                    <phase>generate-sources</phase>
                    <goals>
                        <goal>
                            compile
                        </goal>
                    </goals>
                    <configuration>
                        <source>1.6</source>
                        <target>1.6</target>
                        <optimize>true</optimize>
                        <showDeprecation>true</showDeprecation>
                        <showWarnings>true</showWarnings>
                        <proc>only</proc>
                        <!--<compilerArgument>-Aeclipselink.metamodel=true</compilerArgument>
                        <generatedSourcesDirectory>${basedir}/src/main/java</generatedSourcesDirectory>-->
                    </configuration>
                </execution>
            </executions>
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>build-helper-maven-plugin</artifactId>
            <version>1.8</version>
            <executions>
                <execution>
                    <id>add-modelgen-generated-sources-directory</id>
                    <phase>generate-sources</phase>
                    <goals>
                        <goal>add-source</goal>
                    </goals>
                    <configuration>
                        <sources>
                            <source>${project.build.directory}/target/generated-sources/annotations</source>
                        </sources>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

add-sources 部分是为了让 netbeans 8 理解它以将其放入类路径中 :)