Why is this an issue?

Rather than creating a boxed primitive from a String to extract the primitive value, use the relevant parse method instead. Using parse makes the code more efficient and the intent of the developer clearer.

Noncompliant code example

String myNum = "42.0";
float myFloat = new Float(myNum);  // Noncompliant
float myFloatValue = (new Float(myNum)).floatValue();  // Noncompliant
int myInteger = Integer.valueOf(myNum); // Noncompliant
int myIntegerValue = Integer.valueOf(myNum).intValue(); // Noncompliant

Compliant solution

String myNum = "42.0";
float f = Float.parseFloat(myNum);
int myInteger = Integer.parseInt(myNum);