1package io.protobase.f7.utils;
 2
 3public class Filters {
 4  /**
 5   * Used to filter lists to values that are numeric: they are a Boolean, or a Double.
 6   *
 7   * @param value - to check
 8   * @return - true if value is instance of Double, or Boolean. Otherwise false.
 9   */
10  public static boolean isNumeric(Object value) {
11    return value instanceof Double || value instanceof Boolean;
12  }
13
14  /**
15   * Is the value a numeric value (Double or Boolean) or a coercable string?
16   *
17   * @param value - to check
18   * @return - true if value is instance of Double, or Boolean, or is a String that can be converted to Double.
19   */
20  public static boolean isCoercableToNumeric(Object value) {
21    return isNumeric(value) || isCoercableString(value);
22  }
23
24  public static boolean isLiteralNumber(Object value) {
25    return value instanceof Double;
26  }
27
28  /**
29   * Can we coerce this string to a number value?
30   *
31   * @param value - to test.
32   * @return true if we can get a Double from this value.
33   */
34  public static boolean isCoercableString(Object value) {
35    if (value instanceof String) {
36      try {
37        Double.parseDouble(Converters.castAsString(value));
38        return true;
39      } catch (NumberFormatException e) {
40        return false;
41      }
42    }
43    return false;
44  }
45}