找不到元素'持久性'的声明

Question

已将persistence.xml放在eclipse中项目的类路径中,因为在错误之前找不到该文件.现在给出了这个错误:

引发者:javax.persistence.PersistenceException:无效的persistence.xml.解析XML时出错[line:-1,column:-1]:cvc-elt.1:找不到元素'persistence'的声明

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.1"
             xsi:schemalocation="http://java.sun.com/xml/ns/persistence
                                 http://java.sun.com/xml/ns/persistence/persistence_2_1.xsd">
    <persistence-unit name="default" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <properties>
            <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
            <property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/Automoveis" />
            <property name="javax.persistence.jdbc.user" value="postgres" />
            <property name="javax.persistence.jdbc.password" value="1234" />
            <property name="javax.persistence.jdbc.driver" value="org.postgresql.jdbc.Driver" />
            <property name="hibernate.show_sql" value="true" />
            <property name="hibernate.format_sql" value="true" />
            <property name="hibernate.hbm2ddl.auto" value="create" />
        </properties>
    </persistence-unit>
</persistence>

Answer 1

问题是你混合了JPA 2.0和JPA 2.1表示法.

这个

<persistence xmlns="http://xmlns.jcp.org/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
                                 http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd"
  version="2.1">

对于JPA 2.1或此

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
                      http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
  version="2.0">

对于JPA 2而不是其混合.

有关详细信息,请参阅http://www.oracle.com/webfolder/technetwork/jsc/xml/ns/persistence/index.html.

Answer 2

提供的 XML 有点问题，可能是缺少版本，也可能是 XML 定义。也可能是一个奇怪的字符或某个地方的拼写错误。

下面是一个工作模板，请尝试一下。

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
         version="2.0">
....
</persistence> 

Answer 3

解决了！

我不知道到底出了什么问题，但效果很好：

<persistence version="2.0"   
xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">    

<persistence-unit name="default" transaction-type="RESOURCE_LOCAL">    
    <provider>org.hibernate.ejb.HibernatePersistence</provider>    

    <properties>    
        <property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver" />    
        <property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/Automoveis" />    
        <property name="javax.persistence.jdbc.user" value="postgres" />    
        <property name="javax.persistence.jdbc.password" value="1234" />    
        <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />               
        <property name="hibernate.hbm2ddl.auto" value="update" />    
        <property name="hibernate.show_sql" value="true" />    
        <property name="hibernate.format_sql" value="true"/>    
    </properties>    
</persistence-unit>