2

如何在 Grails 3.0.1 中使用注释映射域类？

以下步骤对我不起作用。

步骤 1。我用 Grails 3.0.1 ( grails create-app books) 创建了一个新应用程序。

步骤 2。如使用 Hibernate Annotations 进行映射中所述，我在src/main/com/books/Book.groovy（也尝试src/main/groovy/com/books/Book.groovy过）中创建了一个新类

package com.books;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Book {
    private Long id;
    private String title;
    private String description;
    private Date date;

    @Id
    @GeneratedValue
    public Long getId() {
        return id;
    }

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

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }
}

步骤 3。然后通过将相关条目添加到文件中，向 Hibernate sessionFactory 注册该类，grails-app/conf/hibernate/hibernate.cfg.xml如下所示：

<!DOCTYPE hibernate-configuration SYSTEM
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <mapping package="com.books" />
        <mapping class="com.books.Book" />
    </session-factory>
</hibernate-configuration>

第 4 步。启动应用程序 ( grails run-app) 后，“欢迎使用 Grails”页面 ( grails-app/views/index.gsp) 报告零域类，这意味着映射没有生效：

  • grails 运行应用程序
  • 加载本地主机：8080
  • 注意“ARTEFACTS”部分下的“Domains: 0”

Grails 3.0.1 中的相关异常

如果我查询上面的域类，会抛出以下异常

Caused by: org.hibernate.hql.internal.ast.QuerySyntaxException: Book is not mapped
    at org.hibernate.hql.internal.ast.util.SessionFactoryHelper.requireClassPersister(SessionFactoryHelper.java:189) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.ast.tree.FromElementFactory.addFromElement(FromElementFactory.java:109) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
       .hibernate.hql.internal.ast.tree.FromClause.addFromElement(FromClause.java:95) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.ast.HqlSqlWalker.createFromElement(HqlSqlWalker.java:332) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElement(HqlSqlBaseWalker.java:3678) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElementList(HqlSqlBaseWalker.java:3567) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromClause(HqlSqlBaseWalker.java:708) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:564) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:301) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:249) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:278) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:206) ~[hibernate-core-4.3.8.Final.jar:4.3.8.Final]
    ... 40 common frames omitted
4

1 回答 1

1

正如 Graeme 建议的那样，解决方案是放入hibernate.cfg.xml而grails-app/conf不是grails-app/conf/hibernate，否则配置将不会生效。我已经提交了一个拉取请求以在相关文档中反映这一点，我希望更新能够尽快生效，以防止其他用户面临同样的问题。

于 2015-06-26T21:17:09.847 回答