goja-core/src/main/java/goja/core/db/Dao.java
public static <M extends Model> boolean isNew(M m, String pk_column) {
        final Object val = m.get(pk_column);
        return val == null || val instanceof Number && ((Number) val).intValue() <= 0;
    }
public static <M extends Model> boolean isNew(M m, String pk_column) {
        final Object val = m.get(pk_column);
        return val == null || val instanceof Number && ((Number) val).intValue() <= 0;
    }
According to the primary key and entity determine whether for the new entity.

@param m         Database model.
@param pk_column PK Column.
@param <M>       Generic entity references.
@return If for the new form of return true.