48 lines
1010 B
Plaintext
48 lines
1010 B
Plaintext
== Why is this an issue?
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Calling ``++toString()++`` or ``++clone()++`` on an object should always return a string or an object. Returning ``++null++`` instead contravenes the method's implicit contract.
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=== Noncompliant code example
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[source,java]
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----
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public String toString () {
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if (this.collection.isEmpty()) {
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return null; // Noncompliant
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} else {
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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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public String toString () {
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if (this.collection.isEmpty()) {
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return "";
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} else {
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// ...
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----
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== Resources
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* CWE - https://cwe.mitre.org/data/definitions/476[CWE-476 - NULL Pointer Dereference]
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* https://wiki.sei.cmu.edu/confluence/x/aDdGBQ[CERT, EXP01-J.] - Do not use a null in a case where an object is required
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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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'''
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== Comments And Links
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(visible only on this page)
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include::../comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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