When boxed type `java.lang.Boolean` is used as an expression to determine the control flow (as described in https://docs.oracle.com/javase/specs/jls/se8/html/jls-4.html#jls-4.2.5[Java Language Specification §4.2.5 The `boolean` Type and boolean Values]) it will throw a `NullPointerException` if the value is `null` (as defined in https://docs.oracle.com/javase/specs/jls/se8/html/jls-5.html#jls-5.1.8[Java Language Specification §5.1.8 Unboxing Conversion]). It is safer to avoid such conversion altogether and handle the `null` value explicitly. Note, however, that no issues will be raised for Booleans that have already been null-checked. == Noncompliant Code Example [source,java] ---- Boolean b = getBoolean(); if (b) { // Noncompliant, it will throw NPE when b == null foo(); } else { bar(); } ---- == Compliant Solution [source,java] ---- Boolean b = getBoolean(); if (Boolean.TRUE.equals(b)) { foo(); } else { bar(); // will be invoked for both b == false and b == null } Boolean b = getBoolean(); if(b != null){ String test = b ? "test" : ""; } ---- == See * https://docs.oracle.com/javase/specs/jls/se8/html/jls-5.html#jls-5.1.8[Java Language Specification §5.1.8 Unboxing Conversion] ifdef::env-github,rspecator-view[] ''' == Implementation Specification (visible only on this page) include::message.adoc[] include::highlighting.adoc[] endif::env-github,rspecator-view[]