code: public static void validate(SpiExpressionList<?> expressions,
                                  ListExpressionValidation validation,
                                  boolean ignoreUnknown) {
          if (expressions == null) return;
          List<SpiExpression> list = expressions.getUnderlyingList();
          Iterator<SpiExpression> it = list.iterator();
          while (it.hasNext()) {
              it.next().validate(validation);
              if (ignoreUnknown && !validation.lastValid()) {
                  it.remove();
              }
          }
      }
docs: <p>validate.</p>
  
  @param expressions   a {@link io.ebeaninternal.api.SpiExpressionList} object.
  @param validation    a {@link ameba.db.ebean.internal.ListExpressionValidation} object.
  @param ignoreUnknown a boolean.