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MisplacedNullCheck

MisplacedNullCheck

The null check here is misplaced. If the variable is null a NullPointerException will be thrown. Either the check is useless (the variable will never be “null”) or it is incorrect.


    
//Expression
    /*[self::ConditionalOrExpression or self::ConditionalAndExpression]
    /descendant::PrimaryExpression/PrimaryPrefix
    /Name[starts-with(@Image,
        concat(ancestor::PrimaryExpression/following-sibling::EqualityExpression
            [./PrimaryExpression/PrimaryPrefix/Literal/NullLiteral]
            /PrimaryExpression/PrimaryPrefix
            /Name[count(../../PrimarySuffix)=0]/@Image,".")
        )
     ]
     [count(ancestor::ConditionalAndExpression/EqualityExpression
            [@Image='!=']
            [./PrimaryExpression/PrimaryPrefix/Literal/NullLiteral]
            [starts-with(following-sibling::*/PrimaryExpression/PrimaryPrefix/Name/@Image,
                concat(./PrimaryExpression/PrimaryPrefix/Name/@Image, '.'))]
      ) = 0
     ]
    

Example(s):


    
public class Foo {
	void bar() {
		if (a.equals(baz) && a != null) {}
		}
}
    

Example(s):


public class Foo {
	void bar() {
		if (a.equals(baz) || a == null) {}
	}
}