63e5b7219b
## Review A dedicated reviewer checked the rule description successfully for: - [x] logical errors and incorrect information - [x] information gaps and missing content - [x] text style and tone - [x] PR summary and labels follow [the guidelines](https://github.com/SonarSource/rspec/#to-modify-an-existing-rule)
77 lines
2.1 KiB
Plaintext
77 lines
2.1 KiB
Plaintext
== Why is this an issue?
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Using wildcards in imports may look cleaner as it reduces the number of lines in the import section and simplifies the code. +
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On the other hand, it makes the code harder to maintain:
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* It reduces code readability as developers will have a hard time knowing where names come from.
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* It could lead to conflicts between names defined locally and the ones imported.
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* It could later raise conflicts on dependency upgrade or Java version migration, as a wildcard import that works today might be broken tomorrow.
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That is why it is better to import only the specific classes or modules you need.
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=== Exceptions
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Static imports are ignored by this rule. For example:
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[source,java]
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----
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import static java.lang.Math.*;
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----
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will not raise an issue;
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== How to fix it
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Depending on your IDE you can solve this issue almost **automatically**: +
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Look for **Organize/Optimize imports** actions.
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These actions can also often be applied automatically on save. +
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__Note:__ To make this work properly, you must adjust IDE settings to use a very high `allowed class count usage` before using wildcards.
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Resolving this issue **manually** will require a step-by-step approach:
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. Remove one wildcard import and note down compilation failures.
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. For each missing class, import it back with the package prefix.
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. When the code compiles again, proceed with the next wildcard import.
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=== Code examples
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==== Noncompliant code example
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[source,java,diff-id=1,diff-type=noncompliant]
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----
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import java.sql.*; // Noncompliant
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import java.util.*; // Noncompliant
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private Date date; // Date class exists in java.sql and java.util. Which one is this?
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----
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==== Compliant solution
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[source,java,diff-id=1,diff-type=compliant]
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----
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import java.sql.Date;
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import java.util.List;
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import java.util.ArrayList;
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private Date date;
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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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Explicitly import the specific classes needed.
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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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