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Code Analyzer for Java

There is a newer version: 8.10.0.38194

Why is this an issue?
It’s almost always a mistake to compare two instances of java.lang.String or boxed types like java.lang.Integer using
reference equality == or !=, because it is not comparing actual value but locations in memory.
Noncompliant code example
String firstName = getFirstName(); // String overrides equals
String lastName = getLastName();

if (firstName == lastName) { ... }; // Non-compliant; false even if the strings have the same value

Compliant solution
String firstName = getFirstName();
String lastName = getLastName();

if (firstName != null && firstName.equals(lastName)) { ... };

Resources

   CWE - CWE-595 - Comparison of Object References Instead of Object Contents 
   CWE - CWE-597 - Use of Wrong Operator in String Comparison 
   CERT, EXP03-J. - Do not use the equality operators when comparing values of boxed
  primitives 
   CERT, EXP50-J. - Do not confuse abstract object equality with reference equality