40 lines
889 B
Plaintext
40 lines
889 B
Plaintext
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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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----
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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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----
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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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== 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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