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.
68 lines
1.4 KiB
Plaintext
68 lines
1.4 KiB
Plaintext
== Why is this an issue?
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Because ``++Object++`` implements ``++hashCode++``, any Java class can be put into a hash structure. However, classes that define ``++equals(Object)++`` but not ``++hashCode()++`` aren't truly hash-able because instances that are equivalent according to the ``++equals++`` method can return different hashes.
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=== Noncompliant code example
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[source,java]
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----
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public class Student { // no hashCode() method; not hash-able
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// ...
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public boolean equals(Object o) {
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// ...
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}
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}
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public class School {
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private Map<Student, Integer> studentBody = // okay so far
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new HashTable<Student, Integer>(); // Noncompliant
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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 Student { // has hashCode() method; hash-able
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// ...
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public boolean equals(Object o) {
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// ...
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}
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public int hashCode() {
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// ...
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}
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}
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public class School {
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private Map<Student, Integer> studentBody = new HashTable<Student, Integer>();
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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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== Implementation Specification
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(visible only on this page)
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=== Message
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Add a "hashCode()" method to "className" or remove it from this hash.
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'''
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== Comments And Links
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(visible only on this page)
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=== on 11 Oct 2014, 11:55:56 Freddy Mallet wrote:
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Perfect and relates to RSPEC-1206 without any overlap.
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endif::env-github,rspecator-view[]
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