如何将Postgres JSONB数据类型与JPA一起使用?
2022-09-01 10:53:13
我没有找到一种方法来使用JPA(EclipseLink)从PostgreSQL映射JSON和JSONB数据类型。是否有人将此数据类型与JPA一起使用,并且可以给我一些工作示例?
我没有找到一种方法来使用JPA(EclipseLink)从PostgreSQL映射JSON和JSONB数据类型。是否有人将此数据类型与JPA一起使用,并且可以给我一些工作示例?
所有的答案都帮助我达到了为JPA准备的最终解决方案,而不是EclipseLink或Hibernate。
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.io.IOException;
import javax.json.Json;
import javax.json.JsonObject;
import javax.persistence.Converter;
import org.postgresql.util.PGobject;
@Converter(autoApply = true)
public class JsonConverter implements javax.persistence.AttributeConverter<JsonObject, Object> {
private static final long serialVersionUID = 1L;
private static ObjectMapper mapper = new ObjectMapper();
@Override
public Object convertToDatabaseColumn(JsonObject objectValue) {
try {
PGobject out = new PGobject();
out.setType("json");
out.setValue(objectValue.toString());
return out;
} catch (Exception e) {
throw new IllegalArgumentException("Unable to serialize to json field ", e);
}
}
@Override
public JsonObject convertToEntityAttribute(Object dataValue) {
try {
if (dataValue instanceof PGobject && ((PGobject) dataValue).getType().equals("json")) {
return mapper.reader(new TypeReference<JsonObject>() {
}).readValue(((PGobject) dataValue).getValue());
}
return Json.createObjectBuilder().build();
} catch (IOException e) {
throw new IllegalArgumentException("Unable to deserialize to json field ", e);
}
}
}
编辑:我现在看到这几乎是依赖性的。但也许你可以找到类似的东西。Hibernate
EclipseLink
我只是添加我所拥有的作为答案的内容,它起源于另一个SO答案,但无论如何。这将映射到 谷歌 ,但如果需要,您可以将其更改为其他内容。要更改为其他内容,请更改 和 方法。jsonb
JsonObject
gson
nullSafeGet
nullSafeSet
deepCopy
public class JsonbType implements UserType {
@Override
public int[] sqlTypes() {
return new int[] { Types.JAVA_OBJECT };
}
@Override
public Class<JsonObject> returnedClass() {
return JsonObject.class;
}
@Override
public boolean equals(final Object x, final Object y) {
if (x == y) {
return true;
}
if (x == null || y == null) {
return false;
}
return x.equals(y);
}
@Override
public int hashCode(final Object x) {
if (x == null) {
return 0;
}
return x.hashCode();
}
@Nullable
@Override
public Object nullSafeGet(final ResultSet rs,
final String[] names,
final SessionImplementor session,
final Object owner) throws SQLException {
final String json = rs.getString(names[0]);
if (json == null) {
return null;
}
final JsonParser jsonParser = new JsonParser();
return jsonParser.parse(json).getAsJsonObject();
}
@Override
public void nullSafeSet(final PreparedStatement st,
final Object value,
final int index,
final SessionImplementor session) throws SQLException {
if (value == null) {
st.setNull(index, Types.OTHER);
return;
}
st.setObject(index, value.toString(), Types.OTHER);
}
@Nullable
@Override
public Object deepCopy(@Nullable final Object value) {
if (value == null) {
return null;
}
final JsonParser jsonParser = new JsonParser();
return jsonParser.parse(value.toString()).getAsJsonObject();
}
@Override
public boolean isMutable() {
return true;
}
@Override
public Serializable disassemble(final Object value) {
final Object deepCopy = deepCopy(value);
if (!(deepCopy instanceof Serializable)) {
throw new SerializationException(
String.format("deepCopy of %s is not serializable", value), null);
}
return (Serializable) deepCopy;
}
@Nullable
@Override
public Object assemble(final Serializable cached, final Object owner) {
return deepCopy(cached);
}
@Nullable
@Override
public Object replace(final Object original, final Object target, final Object owner) {
return deepCopy(original);
}
}
要使用此功能,请执行以下操作:
public class SomeEntity {
@Column(name = "jsonobject")
@Type(type = "com.myapp.JsonbType")
private JsonObject jsonObject;
此外,您需要设置方言以指示 = :JAVA_OBJECT
jsonb
registerColumnType(Types.JAVA_OBJECT, "jsonb");