Handling Null values in postgres for text array type column in org.hibernate.PropertyAccessException - spring

Question

we got a strange scenario in our Hibernate based web application.
On the Database postgresql,there is a column field of text[] type and some of the values are Null. In my entity class I have mapped it to String[] and When I run a CriteriaBuilder select query I am getting exception saying
Request processing failed; nested exception is javax.persistence.PersistenceException: org.hibernate.PropertyAccessException: could not set a field value by reflection setter
I am using #Type(type = "GenericArrayUserType") annotation on String[] in entity class.

Answer 1

Please use the below custom GenericStringArrayUserType mapping for your String[] attribute.
#Type(type = "ai.test.GenericStringArrayUserType")
private String[] fields;
import org.hibernate.HibernateException;
import org.hibernate.engine.spi.SessionImplementor;
import org.hibernate.usertype.UserType;
public class GenericStringArrayUserType<T extends Serializable> implements UserType {
protected static final int[] SQL_TYPES = {Types.ARRAY};
private Class<T> typeParameterClass;
#Override
public int[] sqlTypes() {
return new int[]{Types.ARRAY};
}
#Override
public Class<T> returnedClass() {
return typeParameterClass;
}
#Override
public boolean equals(Object x, Object y) throws HibernateException {
if (x == null) {
return y == null;
}
return x.equals(y);
}
#Override
public int hashCode(Object x) throws HibernateException {
return x.hashCode();
}
#Override
public Object nullSafeGet(ResultSet resultSet, String[] names, SessionImplementor session, Object owner)
throws HibernateException, SQLException {
/*
if (resultSet.wasNull()) {
return null;
}
*/
if (resultSet.getArray(names[0]) == null) {
return new String[0];
}
Array array = resultSet.getArray(names[0]);
#SuppressWarnings("unchecked")
T javaArray = (T) array.getArray();
return javaArray;
}
#Override
public void nullSafeSet(PreparedStatement statement, Object value, int index, SessionImplementor session)
throws HibernateException, SQLException {
Connection connection = statement.getConnection();
if (value == null) {
statement.setNull(index, SQL_TYPES[0]);
} else {
#SuppressWarnings("unchecked")
T castObject = (T) value;
Array array = connection.createArrayOf("text", (Object[]) castObject);
statement.setArray(index, array);
}
}
#Override
public Object deepCopy(Object value) throws HibernateException {
return value;
}
#Override
public boolean isMutable() {
return true;
}
#SuppressWarnings("unchecked")
#Override
public Serializable disassemble(Object value) throws HibernateException {
return (T) this.deepCopy(value);
}
#Override
public Object assemble(Serializable cached, Object owner) throws HibernateException {
return this.deepCopy(cached);
}
#Override
public Object replace(Object original, Object target, Object owner) throws HibernateException {
return original;
}
}