EqualsNull

Inexperienced programmers sometimes confuse comparison concepts and use equals() to compare to null.

This rule is defined by the following XPath expression:

    
//PrimaryExpression
 [
PrimaryPrefix/Name[ends-with(@Image, 'equals')]
or
PrimarySuffix[ends-with(@Image, 'equals')]
]
[PrimarySuffix/Arguments/ArgumentList[count(Expression)=1]
  /Expression/PrimaryExpression/PrimaryPrefix
   /Literal/NullLiteral]
    
                

Example:

                
       
class Bar {
   void foo() {
       String x = "foo";
       if (x.equals(null)) { // bad!
        doSomething();
       }
   }
}