postgresql - JPA 错误 QuerySyntaxException：播放器未映射 [SELECT p FROM Player p]

Question

我正在尝试使用 JPA 在 eclipse 微配置文件中执行简单的 get 查询，这样：

班级球员：

@Entity
@Table(name = "player")
public class Player {...

主类：

@ApplicationScoped
@Path("/hello2")
public class HelloWorld extends Application {





    @Path("/players")
    @GET
    public List<Player> getPlayers() {
        EntityManager entityManager = Persistence.createEntityManagerFactory("testMicroProfile").createEntityManager();
        EntityTransaction transaction = entityManager.getTransaction();
        List<Player> list  = null;
        transaction.begin();
        TypedQuery<Player> query = entityManager.createQuery("SELECT p FROM Player p", Player.class);
        list = query.getResultList();
        transaction.commit();
        return list;
    }


}

这是文件 persistence.xml：

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" 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">
    <persistence-unit name="testMicroProfile" transaction-type="RESOURCE_LOCAL">
        <properties>
            <property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/microprofiledb"/>
            <property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver"/>
            <property name="javax.persistence.jdbc.user" value="user"/>
            <property name="javax.persistence.jdbc.password" value="psw"/>
        </properties>
    </persistence-unit>
</persistence>

数据库中表的名称是player，但我在 stackoverflow 上的另一个答案中读到我必须在查询中使用类的名称，所以我在“播放器”中更改了它，但不起作用反正。少了什么东西？

Answer 1

尝试将您的实体类添加到persistence.xml：

<persistence-unit name="testMicroProfile">
    <class>my.test.Player</class>