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