1

私は本「Beginning Java EE 6 Platform with GlassFish 3」の第2章の例に従おうとしています.WindowsのcmdからEclipseLink、Derby、およびMavenを使用しています。私は本当にこれを理解することができず、助けに感謝します!

私の Main.java クラスのこの行EntityManagerFactory emf = Persistence.createEntityManagerFactory("chapter02PU");は、次のエラーを生成します。

    [INFO] Error stacktraces are turned on.
    [INFO] Scanning for projects...
    [INFO]                                                                         
    [INFO] ------------------------------------------------------------------------
    [INFO] Building Chapter 02 - JPA 0.1
    [INFO] ------------------------------------------------------------------------
    [INFO] 
    [INFO] --- maven-resources-plugin:2.5:resources (default-resources) @ chapter02 ---
    [debug] execute contextualize
    [WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
    [INFO] Copying 1 resource
    [INFO] 
    [INFO] --- maven-compiler-plugin:2.3.2:compile (default-compile) @ chapter02 ---
    [INFO] Nothing to compile - all classes are up to date
    [INFO] 
    [INFO] >>> exec-maven-plugin:1.2.1:java (default-cli) @ chapter02 >>>
    [INFO] 
    [INFO] <<< exec-maven-plugin:1.2.1:java (default-cli) @ chapter02 <<<
    [INFO] 
    [INFO] --- exec-maven-plugin:1.2.1:java (default-cli) @ chapter02 ---
    [WARNING] 
    java.lang.reflect.InvocationTargetException
        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:601)
        at org.codehaus.mojo.exec.ExecJavaMojo$1.run(ExecJavaMojo.java:297)
        at java.lang.Thread.run(Thread.java:722)
    Caused by: java.lang.NoClassDefFoundError: javax/persistence/Persistence
        at org.beginningee6.book.chapter02.Main.main(Main.java:22)
        ... 6 more
    Caused by: java.lang.ClassNotFoundException: javax.persistence.Persistence
        at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
        ... 7 more
    [INFO] ------------------------------------------------------------------------
    [INFO] BUILD FAILURE
    [INFO] ------------------------------------------------------------------------
    [INFO] Total time: 8.390s
    [INFO] Finished at: Tue Mar 19 23:13:36 CET 2013
    [INFO] Final Memory: 8M/105M
    [INFO] ------------------------------------------------------------------------
    [ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:java (default-cli) on project chapter02: An exception occured while executing the Java class. null: InvocationTargetException: javax/persistence/Persistence: javax.persistence.Persistence -> [Help 1]
    org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:java (default-cli) on project chapter02: An exception occured while executing the Java class. null
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:217)
        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:601)
        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)
    Caused by: org.apache.maven.plugin.MojoExecutionException: An exception occured while executing the Java class. null
        at org.codehaus.mojo.exec.ExecJavaMojo.execute(ExecJavaMojo.java:352)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
        ... 19 more
    Caused by: java.lang.reflect.InvocationTargetException
        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:601)
        at org.codehaus.mojo.exec.ExecJavaMojo$1.run(ExecJavaMojo.java:297)
        at java.lang.Thread.run(Thread.java:722)
    Caused by: java.lang.NoClassDefFoundError: javax/persistence/Persistence
        at org.beginningee6.book.chapter02.Main.main(Main.java:22)
        ... 6 more
    Caused by: java.lang.ClassNotFoundException: javax.persistence.Persistence
        at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
        ... 7 more
    [ERROR] 
    [ERROR] Re-run Maven using the -X switch to enable full debug logging.
    [ERROR] 
    [ERROR] For more information about the errors and possible solutions, please read the following articles:
    [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

これは私の Main.java クラスです:

package org.beginningee6.book.chapter02;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;

public class Main {

    public static void main(String[] args) {

        Book book = new Book();
        book.setTitle("The Hitchhicker's Guide to the Galaxy");
        book.setPrice(12.5F);
        book.setDescription("SCience fiction comedy book");
        book.setIsbn("1-84023-742-2");
        book.setNbOfPage(354);
        book.setIllustrations(false);

        // Get en entity manager and a transaction
        EntityManagerFactory emf = Persistence.createEntityManagerFactory("chapter02PU");
        //EntityManager em = emf.createEntityManager();

        //Persist the book to the database
        /*EntityTransaction tx = em.getTransaction();
        tx.begin();
        em.persist(book);
        tx.commit();

        em.close();
        emf.close();*/
    }

}

これは私の Book.java クラスです:

package org.beginningee6.book.chapter02;


import javax.persistence.*;

@Entity
@NamedQuery(name = "findAllBooks", query = "SELECT b FROM Book b")
public class Book {
    @Id
    @GeneratedValue
    private Long id;
    @Column(nullable = false)
    private String title;
    private Float price;
    @Column(length = 2000)
    private String description;
    private String isbn;
    private Integer nbOfPage;
    private Boolean illustrations;

    public Book() {

    }

//Plus getters and setter.

これは私のpersistence.xmlファイルです:

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/persistence">
    <persistence-unit name="chapter02PU" transaction-type="RESOURCE_LOCAL">
        <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
        <class>org.beginningee6.book.chapter02.Book</class>
        <properties>
            <property name="eclipselink.target-database" value="DERBY"/>
            <property name="eclipselink.ddl-generation" value="create-tables"/>
            <property name="eclipselink.logging.level" value="INFO"/>
            <property name="javax.persistence.jdbc.driver" value="org.apache.derby.jdbc.EmbeddedDriver"/>
            <property name="javax.persistence.jdbc.url" value="jdbc:derby:memory:chapter02DB;create=true"/> 
            <!-- <property name="javax.persistence.jdbc.driver" value="org.apache.derby.jdbc.ClientDriver"/>
            <property name="javax.persistence.jdbc.url" value="jdbc:derby://localhost:1527/chapter02DB;create=true"/> -->
            <property name="javax.persistence.jdbc.user" value="APP"/>
            <property name="javax.persistence.jdbc.password" value="APP"/>
        </properties>
    </persistence-unit>
</persistence>

これは私のpom.xmlファイルです:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

        <modelVersion>4.0.0</modelVersion>
        <groupId>org.beginningee6.book</groupId>
        <artifactId>chapter02</artifactId>
        <version>0.1</version>
        <name>Chapter 02 - JPA</name>    

        <dependencies>
            <dependency>
                <groupId>org.eclipse.persistence</groupId>
                <artifactId>javax.persistence</artifactId>
                <version>2.0.0</version>
                <scope>provided</scope>
            </dependency> 
            <dependency>
                <groupId>org.eclipse.persistence</groupId>
                <artifactId>eclipselink</artifactId>
                <version>2.4.0</version>
                <scope>provided</scope>
            </dependency>
            <dependency>
                <groupId>org.apache.derby</groupId>
                <artifactId>derbyclient</artifactId>
                <version>10.8.2.2</version>
            </dependency>
            <dependency>
                <groupId>org.apache.derby</groupId>
                <artifactId>derby</artifactId>
                <version>10.8.2.2</version>
            </dependency>
        </dependencies>

</project>

そして、これはEclipseでの私のファイル構造です:

JavaEEAPress\src\main\java\org\beginningee6\book\chapter02\Book.java
JavaEEAPress\src\main\java\org\beginningee6\book\chapter02\Main.java
JavaEEAPress\src\main\resources\META-INF\persistence.xml
JavaEEAPress\pom.xml
4

2 に答える 2

3

provided持続性ライブラリにスコープを指定しました。

<dependency>
    <groupId>org.eclipse.persistence</groupId>
    <artifactId>javax.persistence</artifactId>
    <version>2.0.0</version>
    <scope>provided</scope>
</dependency>
<dependency>
    <groupId>org.eclipse.persistence</groupId>
    <artifactId>eclipselink</artifactId>
    <version>2.4.0</version>
    <scope>provided</scope>
</dependency>

これは基本的に、「コンパイルの目的でこれらのライブラリを使用しますが、最終的には他の手段で提供されるため、最終的なアーティファクトには含めないでください」と Maven に伝えます。コードをアプリケーション サーバーにデプロイして実行することが想定されているため、あなたがフォローしているチュートリアルでは、このように定義されていると確信しています。このようなシナリオでは、それらのライブラリが実際に提供されます。

ただし、この場合、スタンドアロンの Java アプリケーションを実行しているため、これらのライブラリを明示的に含める必要があります。最も簡単な修正は、スコープを for から に変更org.eclipse.persistence:javax.persistenceすることorg.eclipse.persistence:eclipselinkです。ただし、サンプルをアプリケーション サーバーにデプロイするつもりがない場合に限ります。より良いオプションは、スタンドアロン コードを実行するためのプロファイルを定義することです。providedruntime

<profiles>
    <profile>
        <id>standalone</id>
        <dependencies>
            <dependency>
                <groupId>org.eclipse.persistence</groupId>
                <artifactId>javax.persistence</artifactId>
                <version>2.0.0</version>
                <scope>provided</scope>
            </dependency>
            <dependency>
                <groupId>org.eclipse.persistence</groupId>
                <artifactId>eclipselink</artifactId>
                <version>2.4.0</version>
                <scope>provided</scope>
            </dependency>
        </dependencies>
    </profile>
</profiles>

これは、プロファイル オプションを指定して Maven を実行することでアクティブ化されます。

mvn clean install -Pstandalone

于 2013-03-19T22:57:52.010 に答える