Rule Definition
The program could wind up using the wrong number and generate incorrect results. If the number is used to allocate resources or make a security decision, then this could introduce a vulnerability. - A widening conversion of an int or a long value to float, or of a long value to double, may result in loss of precision - that is, the result may lose some of the least significant bits of the value. In this case, the resulting floating-point value will be a correctly rounded version of the integer value, using IEEE 754 round-to-nearest mode

Remediation
You can use Widening Primitive Conversion to avoid loss of precision.

Violation Code Sample

int i = (int) 33457.8f;
short i1 = (short)ic.readdata(); // VIOLATION if readdata returns long
int i1 = 1 + 2+ (int)3.5 // VIOLATION

Fixed Code Sample

A widening primitive conversion does not lose information about the overall magnitude of a numeric value.
	byte to short, int, long, float, or double
    short to int, long, float, or double
    char to int, long, float, or double
    int to long, float, or double
    long to float or double
    float to double
-Despite the fact that loss of precision may occur, a widening primitive conversion never results in a run-time exception

https://cwe.mitre.org/data/definitions/681.html http://www.informit.com/articles/article.aspx?p=174371