16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
51 lines
1.1 KiB
Plaintext
51 lines
1.1 KiB
Plaintext
== Why is this an issue?
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The ``++hasNext++`` method of an ``++Iterator++`` should only report on the state of the iterator, not change it. Making a change to an iterator in its ``++hasNext++`` method violates all expectations of what the method will do, and almost guarantees bad results when the iterator class is used.
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=== Noncompliant code example
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[source,java]
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----
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public class MyItr implements Iterator<MyClass> {
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//...
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public boolean hasNext() {
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if (next() != null) { // Noncompliant
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return true;
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}
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return false;
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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 class MyItr implements Iterator<MyClass> {
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private List<MyClass> list;
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private int index = 0;
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//...
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public boolean hasNext() {
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return index < list.size();
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}
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Comments And Links
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(visible only on this page)
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=== duplicates: S1849
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=== on 10 Oct 2014, 15:30:37 Freddy Mallet wrote:
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I would prefer the following rule title @Ann:
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* "Iterator.next()" method should never be called in the "Iterator.hasNext()" method
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endif::env-github,rspecator-view[]
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