rspec/rules/S2183/java/rule.adoc

== Why is this an issue?

Since an ``++int++`` is a 32-bit variable, shifting by more than +/-31 is confusing at best and an error at worst. When the runtime shifts 32-bit integers, it uses the lowest 5 bits of the shift count operand. In other words, shifting an ``++int++`` by 32 is the same as shifting it by 0, and shifting it by 33 is the same as shifting it by 1.


Similarly, when shifting 64-bit integers, the runtime uses the lowest 6 bits of the shift count operand and shifting ``++long++`` by 64 is the same as shifting it by 0, and shifting it by 65 is the same as shifting it by 1.


=== Noncompliant code example

[source,java]
----
public int shift(int a) {
  int x = a >> 32; // Noncompliant
  return a << 48;  // Noncompliant
}
----


=== Compliant solution

[source,java]
----
public int shift(int a) {
  int x = a >> 31;
  return a << 16;
}
----


include::../exceptions.adoc[]


ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

include::../message.adoc[]

'''
== Comments And Links
(visible only on this page)

include::../comments-and-links.adoc[]

endif::env-github,rspecator-view[]