正确映射JPA实体

Question

我有一个查询，当通过MySQL工作台运行时，得到的结果与预期的一样。

select * from route_generations JOIN linked_customers on linked_customers.linked_customer_id = route_generations.customer_id;

然后，我有两个实体/ java类，如下所示：

@Entity
@Table(name = "route_generations")
public class RouteGeneration {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;

@NotNull
private String customerName;

@NotNull
private String numDevices;

@NotNull
private LocalDateTime startDae;

private LocalDateTime endDate;

@NotNull
private double latitude;

@NotNull
private double longitude;

@NotNull
private int userId;

private long linkedId;

@NotNull
private String customerId;

public String getCustomerId() {
    return customerId;
}

public void setCustomerId(String customerId) {
    this.customerId = customerId;
}

public Long getId() {
    return id;
}

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

public String getCustomerName() {
    return customerName;
}

public void setCustomerName(String customerName) {
    this.customerName = customerName;
}

public String getNumDevices() {
    return numDevices;
}

public void setNumDevices(String numDevices) {
    this.numDevices = numDevices;
}

public LocalDateTime getStartDae() {
    return startDae;
}

public void setStartDae(LocalDateTime startDae) {
    this.startDae = startDae;
}

public LocalDateTime getEndDate() {
    return endDate;
}

public void setEndDate(LocalDateTime endDate) {
    this.endDate = endDate;
}

public double getLatitude() {
    return latitude;
}

public void setLatitude(double latitude) {
    this.latitude = latitude;
}

public double getLongitude() {
    return longitude;
}

public void setLongitude(double longitude) {
    this.longitude = longitude;
}

public int getUserId() {
    return userId;
}

public void setUserId(int userId) {
    this.userId = userId;
}

public long getLinkedId() {
    return linkedId;
}

public void setLinkedId(long linkedId) {
    this.linkedId = linkedId;
}

下课：

@Entity
@Table(name = "linked_customers")
public class KinesisLinkedCustomer {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private long linkedId;

@NotNull
private String linkedServiceId;

@NotNull
private String linkedCustomerId;

@NotNull
private String imei;

@NotNull
private long userId;

public long getLinkedId() {
    return linkedId;
}

public void setLinkedId(long linkedId) {
    this.linkedId = linkedId;
}

public String getLinkedServiceId() {
    return linkedServiceId;
}

public void setLinkedServiceId(String linkedServiceId) {
    this.linkedServiceId = linkedServiceId;
}

public String getLinkedCustomerId() {
    return linkedCustomerId;
}

public void setLinkedCustomerId(String linkedCustomerId) {
    this.linkedCustomerId = linkedCustomerId;
}

public String getImei() {
    return imei;
}

public void setImei(String imei) {
    this.imei = imei;
}

public long getUserId() {
    return userId;
}

public void setUserId(long userId) {
    this.userId = userId;
}

然后，我通过JPARepository中的以下定制方法查询数据库：

@Repository
public interface RouteGenerationRepository extends JpaRepository<RouteGeneration, Long> {

@Query("FROM route_generations JOIN linked_customers on linked_customers.linked_customer_id = route_generations.customer_id")
Page<RouteGeneration> getAllLinkedCustomers(Pageable pageable);

}

在应用程序启动时，我得到以下错误：

    Caused by: java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: route_generations is not mapped [FROM route_generations JOIN linked_customers on linked_customers.linked_customer_id = route_generations.customer_id]
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:138) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:181) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:188) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:729) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:104) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
    at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:350) ~[spring-orm-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at com.sun.proxy.$Proxy125.createQuery(Unknown Source) ~[na:na]
    at org.springframework.data.jpa.repository.query.SimpleJpaQuery.validateQuery(SimpleJpaQuery.java:87) ~[spring-data-jpa-2.1.9.RELEASE.jar:2.1.9.RELEASE]
    ... 58 common frames omitted
Caused by: org.hibernate.hql.internal.ast.QuerySyntaxException: route_generations is not mapped [FROM route_generations JOIN linked_customers on linked_customers.linked_customer_id = route_generations.customer_id]
    at org.hibernate.hql.internal.ast.QuerySyntaxException.generateQueryException(QuerySyntaxException.java:79) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.QueryException.wrapWithQueryString(QueryException.java:103) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:219) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:143) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:119) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:80) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:153) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan(AbstractSharedSessionContract.java:611) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:720) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    ... 66 common frames omitted
Caused by: org.hibernate.hql.internal.ast.QuerySyntaxException: route_generations is not mapped
    at org.hibernate.hql.internal.ast.util.SessionFactoryHelper.requireClassPersister(SessionFactoryHelper.java:169) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.ast.tree.FromElementFactory.addFromElement(FromElementFactory.java:91) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.ast.tree.FromClause.addFromElement(FromClause.java:79) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.ast.HqlSqlWalker.createFromElement(HqlSqlWalker.java:331) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElement(HqlSqlBaseWalker.java:3695) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElementList(HqlSqlBaseWalker.java:3584) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromClause(HqlSqlBaseWalker.java:720) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:576) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:313) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:261) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:271) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:191) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    ... 72 common frames omitted

我看了这些答案：

映射JPA实体关系 -JPA ManyToOne实体映射

但是，在尝试了一些建议之后，我仍然遇到错误。 我需要使用：

@OneToMany on the field linked_customer_id in type linked customers

任何帮助将不胜感激！

Answer 1

这是通过在我的存储库类中使用以下查询解决的：

FROM RouteGeneration r JOIN KinesisLinkedCustomer kl on kl.linkedCustomerId = r.customerId

对于以后的读者，请始终记住使用Java字段名而不是数据库列名！