I wrote an attribute converter to use binary 16 instead of char 36 in mysql for primery keys. I added this file to project:
package com.company.jmix02;
import javax.persistence.AttributeConverter;
import javax.persistence.Converter;
import java.nio.ByteBuffer;
import java.util.UUID;
@Converter(autoApply = false)
public class UUIDAttributeConverter implements AttributeConverter<UUID, byte[]> {
@Override
public byte[] convertToDatabaseColumn(UUID uuid) {
if (uuid == null) return null;
byte[] buffer = new byte[16];
ByteBuffer bb = ByteBuffer.wrap(buffer);
bb.putLong(uuid.getMostSignificantBits());
bb.putLong(uuid.getLeastSignificantBits());
return buffer;
}
@Override
public UUID convertToEntityAttribute(byte[] bytes) {
if (bytes == null) return null;
ByteBuffer bb = ByteBuffer.wrap(bytes);
long high = bb.getLong();
long low = bb.getLong();
return new UUID(high, low);
}
}
and even added a UUIDDataType:
package com.company.jmix02;
import io.jmix.core.metamodel.annotation.DatatypeDef;
import io.jmix.core.metamodel.annotation.Ddl;
import io.jmix.core.metamodel.datatype.Datatype;
import javax.annotation.Nullable;
import java.text.ParseException;
import java.util.Locale;
import java.util.UUID;
@DatatypeDef(
id = "UUID",
javaClass = UUID.class,
defaultForClass = true
)
@Ddl("BINARY(16)")
public class UUIDDataType implements Datatype<UUID> {
@Override
public String format(@Nullable Object value) {
if(value instanceof UUID)
return ((UUID) value).toString();
return null;
}
@Override
public String format(@Nullable Object value, Locale locale) {
return format(value);
}
@Nullable
@Override
public UUID parse(@Nullable String value) throws ParseException {
return UUID.fromString(value);
}
@Nullable
@Override
public UUID parse(@Nullable String value, Locale locale) throws ParseException {
return parse(value);
}
}
and in entity:
@Convert(converter = UUIDAttributeConverter.class)
@Column(name = "ID", nullable = false, columnDefinition = "BINARY(16)")
@Id
private UUID id;
but when saving the entity , it throws an exception because convertToDatabaseColumn is not called at all.
