jpa的多模块maven项目依赖问题答案

【问题标题】：Multi module maven project dependency issue with jpajpa的多模块maven项目依赖问题
【发布时间】：2012-11-29 13:10:44
【问题描述】：

我在使用多模块 maven 项目时遇到错误。我尝试通过 eclipse run 作为选项运行“maven install”。

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building mysite-entities 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- maven-resources-plugin:2.5:resources (default-resources) @ mysite-entities ---
[debug] execute contextualize
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] skip non existing resourceDirectory /home/thomas/spring/mysite-parent/mysite-entities/src/main/resources
[INFO] 
[INFO] --- maven-compiler-plugin:2.3.2:compile (default-compile) @ mysite-entities ---
[INFO] Compiling 11 source files to /home/thomas/spring/mysite-parent/mysite-entities/target/classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /home/thomas/spring/mysite-parent/mysite-entities/src/main/java/com/mysite/entities/Mcc.java:[5,24] package javax.persistence does not exist
[ERROR] /home/thomas/spring/mysite-parent/mysite-entities/src/main/java/com/mysite/entities/Mcc.java:[6,24] package javax.persistence does not exist
[ERROR] /home/thomas/spring/mysite-parent/mysite-entities/src/main/java/com/mysite/entities/Mcc.java:[8,1] cannot find symbol
symbol: class Entity
@Entity

mcc.java：

package com.mysite.entities;

import java.io.Serializable;

import javax.persistence.Entity;
import javax.persistence.Id;

@Entity
public class Mcc implements Serializable
{
    /**
     * 
     */
    private static final long serialVersionUID = 4146710247449711520L;

    @Id
    private Long id;

    private String name;

    public Long getId()
    {
        return id;
    }

    public void setId(Long id)
    {
        this.id = id;
    }

    public String getName()
    {
        return name;
    }

    public void setName(String name)
    {
        this.name = name;
    }
}

我的 pom.xml 包括：

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-entitymanager</artifactId>
</dependency>
<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-validator</artifactId>
</dependency>

我检查了引入的 maven 依赖项，它们包括 hibernate-jpa-2.0-api-1.0.1.Final.jar 依次包含所有必要的类。

为什么会出现这个 maven 错误？

【问题讨论】：

您能发布您的pom.xml 和mvn dependency:tree 的输出吗？（或者至少是相关部分 - 例如版本号。）

标签： eclipse maven jpa spring-mvc

【解决方案1】：

实际上存在javax.persistence 的依赖关系。这与 JPA 实现（在您的情况下为 Hibernate）一起使用。

将此添加到您的pom.xml

<dependency>
   <groupId>javax.persistence</groupId>
   <artifactId>persistence-api</artifactId>
   <version>1.0</version>
   <optional>true</optional>
</dependency>

【讨论】：

【解决方案2】：

在某处发现这篇文章，发现这摆脱了警告消息。

将slf4j-api-VERSION.jar和logback-classic-VERSION.jar复制到%JAVA_HOME%\jre\lib\ext

slf4j-api-VERSION.jar位于%M2_REPOSITORY%\org\slf4j\slf4j-api\VERSION\
logback-classic-VERSION.jar位于%M2_REPOSITORY%\ch\qos\logback\logback-classic\VERSION\
如果不使用 logback-classic，则至少 slf4j-log4j12、slf4j-simple、slf4j-jdk14 或 logback-classic 绑定必须在 rhw 类路径中。

【讨论】：