fix AggProductListHelper

@@ -99,13 +99,10 @@ public class AggProductListHelper {
 				try {
 					double value1 = getDouble(o1.get(orderField));
 					double value2 = getDouble(o2.get(orderField));
-					if (value1 == value2) {
-						return 0;
-					}
 					if (isDesc) {
-						return value1 - value2 > 0 ? -1 : 1;
+						return value1 > value2 ? -1 : value1 < value2 ? 1 : 0;
 					} else {
-						return value1 - value2 > 0 ? 1 : -1;
+						return value1 > value2 ? 1 : value1 < value2 ? -1 : 0;
 					}
 				} catch (Exception e) {
 					logger.error(e.getMessage(), e);
@@ -120,24 +117,10 @@ public class AggProductListHelper {
 	}
 
 	private double getDouble(Object value) {
-		if (value == null) {
-			return 0;
-		}
-		if (value instanceof Float) {
-			return ((Float) value).floatValue();
-		}
-		if (value instanceof Integer) {
-			return ((Integer) value);
-		}
-		if (value instanceof Long) {
-			return ((Long) value);
-		}
-		if (value instanceof String) {
-			return Double.valueOf(value.toString());
-		}
-		if (value instanceof Double) {
+		try {
 			return Double.valueOf(value.toString());
+		} catch (Exception e) {
+			return 0;
 		}
-		return 0;
 	}
 }