Java jpa（EclipseLink）生成的左连接查询错误

我有trhee实体（这是我的简化版本），数据库中定义的

Entity1

和

Entity2

之间没有关系。我需要选择（使用外部联接）这样的记录，其中

Entity1

和

Entity2

中的代码以及国家/地区是相同的：

非常简单的JPA查询：

选择a、b
来自Entity1A
左连接实体2b
关于a.code=b.code
a.country=b.country

但当我这样做时，生成了错误的查询：

选择t0.ID、t0.code、t0.COUNTRY\u ID、t1.ID、t1.code、t1.COUNTRY\u ID
从表1到表0
左外连接凸舌2 t1打开（（t0.CODE=t1.CODE）和（t0.COUNTRY_ID=t2.ID））
，c t2
式中（t2.ID=t1.COUNTRY\u ID）

我的意见是，正确的查询包含

左外连接t2 t1打开（（t0.code=t1.code）和（t0.COUNTRY\u ID=t1.COUNTRY\u ID））

不加入

t2

细节 好的，再现问题的所有细节如下：

我有一个maven项目，pom.xml为：

4.0.0
贝特里斯塔

package entity; // in "src/main/java"

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table( name = "c" )
public class Country {

    @Id
    long id;

    @Column
    private String code;

    public long getId() {
        return id;
    }

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

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

}

package entity; // in "src/main/java"

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.Table;

@Entity
@Table( name = "tab1" )
public class Entity1 {

    @Id
    private long id;

    @Column
    private String code;

    @JoinColumn(name = "COUNTRY_ID")
    private Country country;

    public long getId() {
        return id;
    }

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

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public Country getCountry() {
        return country;
    }

    public void setCountry(Country country) {
        this.country = country;
    }


}

package entity; // in "src/main/java"

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.Table;

@Entity
@Table( name = "tab2" )
public class Entity2 {

    @Id
    private long id;

    @Column
    private String code;

    @JoinColumn(name = "COUNTRY_ID")
    private Country country;

    public long getId() {
        return id;
    }

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

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public Country getCountry() {
        return country;
    }

    public void setCountry(Country country) {
        this.country = country;
    }


}

package tests; // in "src/test/java"

import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;

import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.AbstractTransactionalJUnit4SpringContextTests;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = { "classpath:commons-test.xml" })
public class LeftJoinTest extends AbstractTransactionalJUnit4SpringContextTests {

    @PersistenceContext
    protected EntityManager em;

    @Test
    public void test() {
        Assert.assertNotNull(em);
    }

    @Test
    public void testLeftJoin() {
        StringBuilder queryString = new StringBuilder();
        queryString.append(" select a, b " );
        queryString.append("   from Entity1 a ");
        queryString.append("   left join Entity2 b " );
        queryString.append("     on a.code = b.code ");
        queryString.append("    and a.country = b.country ");
        Query query = em.createQuery(queryString.toString());
        List list = query.getResultList();
        Assert.assertEquals( 1, list.size() );
        Object[] oa = (Object[])list.get(0);
        Assert.assertEquals( 2, oa.length );
        System.out.println(list);
    }

}