如何使用JPA和Hibernate映射PostgreSQL枚举 [英] How to map PostgreSQL enum with JPA and Hibernate
问题描述
我正在尝试将名为transmission_result的postgres自定义类型映射到Hibernate/JPA POJO. postgres自定义类型或多或少是字符串值的枚举类型.
我创建了一个名为PGEnumUserType的自定义EnumUserType以及一个表示postgres枚举值的枚举类.当我对一个真实的数据库运行它时,我收到以下错误: '错误:状态"列的类型为transmission_result,但表达式的类型为字符变化 提示:您将需要重写或强制转换表达式. 位置:135'
看到这一点,我想我需要将SqlTypes更改为Types.OTHER.但是这样做会破坏我的集成测试(在内存数据库中使用HyperSQL),并显示以下消息: '原因:java.sql.SQLException:在语句[select enrollment0 _."id"作为id1_47_0_,enrollment0 _."tpa_approval_id"作为tpa2_47_0_,enrollment0 _."tpa_status_code"作为tpa3_47_0_,enrollment0_age,作为状态_4, ."approval_id"作为批准5_47_0_,注册0 _."transmission_date"作为transmis6_47_0_,注册0 _."status"作为status7_47_0_,enrollment0_.传送器"作为transmission8_47_0_,而"transmissions"注册0_,其中enrollment0_.
我不确定为什么更改sqlType会导致此错误.感谢您的帮助.
JPA/休眠实体:
@Entity
@Access(javax.persistence.AccessType.PROPERTY)
@Table(name="transmissions")
public class EnrollmentCycleTransmission {
// elements of enum status column
private static final String ACCEPTED_TRANSMISSION = "accepted";
private static final String REJECTED_TRANSMISSION = "rejected";
private static final String DUPLICATE_TRANSMISSION = "duplicate";
private static final String EXCEPTION_TRANSMISSION = "exception";
private static final String RETRY_TRANSMISSION = "retry";
private Long transmissionID;
private Long approvalID;
private Long transmitterID;
private TransmissionStatusType transmissionStatus;
private Date transmissionDate;
private String TPAApprovalID;
private String TPAStatusCode;
private String TPAStatusMessage;
@Column(name = "id")
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
public Long getTransmissionID() {
return transmissionID;
}
public void setTransmissionID(Long transmissionID) {
this.transmissionID = transmissionID;
}
@Column(name = "approval_id")
public Long getApprovalID() {
return approvalID;
}
public void setApprovalID(Long approvalID) {
this.approvalID = approvalID;
}
@Column(name = "transmitter")
public Long getTransmitterID() {
return transmitterID;
}
public void setTransmitterID(Long transmitterID) {
this.transmitterID = transmitterID;
}
@Column(name = "status")
@Type(type = "org.fuwt.model.PGEnumUserType" , parameters ={@org.hibernate.annotations.Parameter(name = "enumClassName",value = "org.fuwt.model.enrollment.TransmissionStatusType")} )
public TransmissionStatusType getTransmissionStatus() {
return this.transmissionStatus ;
}
public void setTransmissionStatus(TransmissionStatusType transmissionStatus) {
this.transmissionStatus = transmissionStatus;
}
@Column(name = "transmission_date")
public Date getTransmissionDate() {
return transmissionDate;
}
public void setTransmissionDate(Date transmissionDate) {
this.transmissionDate = transmissionDate;
}
@Column(name = "tpa_approval_id")
public String getTPAApprovalID() {
return TPAApprovalID;
}
public void setTPAApprovalID(String TPAApprovalID) {
this.TPAApprovalID = TPAApprovalID;
}
@Column(name = "tpa_status_code")
public String getTPAStatusCode() {
return TPAStatusCode;
}
public void setTPAStatusCode(String TPAStatusCode) {
this.TPAStatusCode = TPAStatusCode;
}
@Column(name = "status_message")
public String getTPAStatusMessage() {
return TPAStatusMessage;
}
public void setTPAStatusMessage(String TPAStatusMessage) {
this.TPAStatusMessage = TPAStatusMessage;
}
}
自定义EnumUserType:
public class PGEnumUserType implements UserType, ParameterizedType {
private Class<Enum> enumClass;
public PGEnumUserType(){
super();
}
public void setParameterValues(Properties parameters) {
String enumClassName = parameters.getProperty("enumClassName");
try {
enumClass = (Class<Enum>) Class.forName(enumClassName);
} catch (ClassNotFoundException e) {
throw new HibernateException("Enum class not found ", e);
}
}
public int[] sqlTypes() {
return new int[] {Types.VARCHAR};
}
public Class returnedClass() {
return enumClass;
}
public boolean equals(Object x, Object y) throws HibernateException {
return x==y;
}
public int hashCode(Object x) throws HibernateException {
return x.hashCode();
}
public Object nullSafeGet(ResultSet rs, String[] names, Object owner) throws HibernateException, SQLException {
String name = rs.getString(names[0]);
return rs.wasNull() ? null: Enum.valueOf(enumClass,name);
}
public void nullSafeSet(PreparedStatement st, Object value, int index) throws HibernateException, SQLException {
if (value == null) {
st.setNull(index, Types.VARCHAR);
}
else {
st.setString(index,((Enum) value).name());
}
}
public Object deepCopy(Object value) throws HibernateException {
return value;
}
public boolean isMutable() {
return false; //To change body of implemented methods use File | Settings | File Templates.
}
public Serializable disassemble(Object value) throws HibernateException {
return (Enum) value;
}
public Object assemble(Serializable cached, Object owner) throws HibernateException {
return cached;
}
public Object replace(Object original, Object target, Object owner) throws HibernateException {
return original;
}
public Object fromXMLString(String xmlValue) {
return Enum.valueOf(enumClass, xmlValue);
}
public String objectToSQLString(Object value) {
return '\'' + ( (Enum) value ).name() + '\'';
}
public String toXMLString(Object value) {
return ( (Enum) value ).name();
}
}
枚举类:
public enum TransmissionStatusType {
accepted,
rejected,
duplicate,
exception,
retry}
我知道了.我需要在nullSafeSet函数中使用setObject而不是setString,并将Types.OTHER作为java.sql.type传递给jdbc,以使其知道它是postgres类型.
public void nullSafeSet(PreparedStatement st, Object value, int index) throws HibernateException, SQLException {
if (value == null) {
st.setNull(index, Types.VARCHAR);
}
else {
// previously used setString, but this causes postgresql to bark about incompatible types.
// now using setObject passing in the java type for the postgres enum object
// st.setString(index,((Enum) value).name());
st.setObject(index,((Enum) value), Types.OTHER);
}
}
I am trying to map a postgres custom type,named transmission_result, to a Hibernate/JPA POJO. The postgres custom type is more or less an enum type of string values.
I have created a custom EnumUserType called PGEnumUserType as well as a enum class representing the postgres enumerated values. When I run this against a real database, I receive the following error: 'ERROR: column "status" is of type transmission_result but expression is of type character varying Hint: You will need to rewrite or cast the expression. Position: 135 '
Upon seeing this, I figured I needed to change my SqlTypes to Types.OTHER. But doing so breaks my integration tests (using HyperSQL in memory DB) with the message : 'Caused by: java.sql.SQLException: Table not found in statement [select enrollment0_."id" as id1_47_0_, enrollment0_."tpa_approval_id" as tpa2_47_0_, enrollment0_."tpa_status_code" as tpa3_47_0_, enrollment0_."status_message" as status4_47_0_, enrollment0_."approval_id" as approval5_47_0_, enrollment0_."transmission_date" as transmis6_47_0_, enrollment0_."status" as status7_47_0_, enrollment0_."transmitter" as transmit8_47_0_ from "transmissions" enrollment0_ where enrollment0_."id"=?]'
I'm not sure why changing the sqlType results in this error. Any help is appreciated.
JPA/Hibernate Entity:
@Entity
@Access(javax.persistence.AccessType.PROPERTY)
@Table(name="transmissions")
public class EnrollmentCycleTransmission {
// elements of enum status column
private static final String ACCEPTED_TRANSMISSION = "accepted";
private static final String REJECTED_TRANSMISSION = "rejected";
private static final String DUPLICATE_TRANSMISSION = "duplicate";
private static final String EXCEPTION_TRANSMISSION = "exception";
private static final String RETRY_TRANSMISSION = "retry";
private Long transmissionID;
private Long approvalID;
private Long transmitterID;
private TransmissionStatusType transmissionStatus;
private Date transmissionDate;
private String TPAApprovalID;
private String TPAStatusCode;
private String TPAStatusMessage;
@Column(name = "id")
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
public Long getTransmissionID() {
return transmissionID;
}
public void setTransmissionID(Long transmissionID) {
this.transmissionID = transmissionID;
}
@Column(name = "approval_id")
public Long getApprovalID() {
return approvalID;
}
public void setApprovalID(Long approvalID) {
this.approvalID = approvalID;
}
@Column(name = "transmitter")
public Long getTransmitterID() {
return transmitterID;
}
public void setTransmitterID(Long transmitterID) {
this.transmitterID = transmitterID;
}
@Column(name = "status")
@Type(type = "org.fuwt.model.PGEnumUserType" , parameters ={@org.hibernate.annotations.Parameter(name = "enumClassName",value = "org.fuwt.model.enrollment.TransmissionStatusType")} )
public TransmissionStatusType getTransmissionStatus() {
return this.transmissionStatus ;
}
public void setTransmissionStatus(TransmissionStatusType transmissionStatus) {
this.transmissionStatus = transmissionStatus;
}
@Column(name = "transmission_date")
public Date getTransmissionDate() {
return transmissionDate;
}
public void setTransmissionDate(Date transmissionDate) {
this.transmissionDate = transmissionDate;
}
@Column(name = "tpa_approval_id")
public String getTPAApprovalID() {
return TPAApprovalID;
}
public void setTPAApprovalID(String TPAApprovalID) {
this.TPAApprovalID = TPAApprovalID;
}
@Column(name = "tpa_status_code")
public String getTPAStatusCode() {
return TPAStatusCode;
}
public void setTPAStatusCode(String TPAStatusCode) {
this.TPAStatusCode = TPAStatusCode;
}
@Column(name = "status_message")
public String getTPAStatusMessage() {
return TPAStatusMessage;
}
public void setTPAStatusMessage(String TPAStatusMessage) {
this.TPAStatusMessage = TPAStatusMessage;
}
}
Custom EnumUserType:
public class PGEnumUserType implements UserType, ParameterizedType {
private Class<Enum> enumClass;
public PGEnumUserType(){
super();
}
public void setParameterValues(Properties parameters) {
String enumClassName = parameters.getProperty("enumClassName");
try {
enumClass = (Class<Enum>) Class.forName(enumClassName);
} catch (ClassNotFoundException e) {
throw new HibernateException("Enum class not found ", e);
}
}
public int[] sqlTypes() {
return new int[] {Types.VARCHAR};
}
public Class returnedClass() {
return enumClass;
}
public boolean equals(Object x, Object y) throws HibernateException {
return x==y;
}
public int hashCode(Object x) throws HibernateException {
return x.hashCode();
}
public Object nullSafeGet(ResultSet rs, String[] names, Object owner) throws HibernateException, SQLException {
String name = rs.getString(names[0]);
return rs.wasNull() ? null: Enum.valueOf(enumClass,name);
}
public void nullSafeSet(PreparedStatement st, Object value, int index) throws HibernateException, SQLException {
if (value == null) {
st.setNull(index, Types.VARCHAR);
}
else {
st.setString(index,((Enum) value).name());
}
}
public Object deepCopy(Object value) throws HibernateException {
return value;
}
public boolean isMutable() {
return false; //To change body of implemented methods use File | Settings | File Templates.
}
public Serializable disassemble(Object value) throws HibernateException {
return (Enum) value;
}
public Object assemble(Serializable cached, Object owner) throws HibernateException {
return cached;
}
public Object replace(Object original, Object target, Object owner) throws HibernateException {
return original;
}
public Object fromXMLString(String xmlValue) {
return Enum.valueOf(enumClass, xmlValue);
}
public String objectToSQLString(Object value) {
return '\'' + ( (Enum) value ).name() + '\'';
}
public String toXMLString(Object value) {
return ( (Enum) value ).name();
}
}
Enum class:
public enum TransmissionStatusType {
accepted,
rejected,
duplicate,
exception,
retry}
I figured it out. I needed to use setObject instead of setString in the nullSafeSet function and pass in the Types.OTHER as the java.sql.type to let jdbc know that it was a postgres type.
public void nullSafeSet(PreparedStatement st, Object value, int index) throws HibernateException, SQLException {
if (value == null) {
st.setNull(index, Types.VARCHAR);
}
else {
// previously used setString, but this causes postgresql to bark about incompatible types.
// now using setObject passing in the java type for the postgres enum object
// st.setString(index,((Enum) value).name());
st.setObject(index,((Enum) value), Types.OTHER);
}
}
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