51369b610e
When an include is not surrounded by empty lines, its content is inlined on the same line as the adjacent content. That can lead to broken tags and other display issues. This PR fixes all such includes and introduces a validation step that forbids introducing the same problem again.
91 lines
1.9 KiB
Plaintext
91 lines
1.9 KiB
Plaintext
== Why is this an issue?
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``++Optional++`` value can hold either a value or not. The value held in the ``++Optional++`` can be accessed using the ``++get()++`` method, but it will throw a
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``++NoSuchElementException++`` if there is no value present. To avoid the exception, calling the ``++isPresent()++`` or ``++! isEmpty()++`` method should always be done before any call to ``++get()++``.
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Alternatively, note that other methods such as ``++orElse(...)++``, ``++orElseGet(...)++`` or ``++orElseThrow(...)++`` can be used to specify what to do with an empty ``++Optional++``.
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=== Noncompliant code example
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[source,java]
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----
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Optional<String> value = this.getOptionalValue();
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// ...
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String stringValue = value.get(); // Noncompliant
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----
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[source,java]
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----
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if (methodThatReturnsOptional().isEmpty()) {
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throw new NotFoundException();
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}
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String value = methodThatReturnsOptional().get(); // Noncompliant: indirect access, we consider that two consecutive calls can return different values.
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----
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=== Compliant solution
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[source,java]
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----
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this.getOptionalValue().ifPresent(stringValue ->
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// Do something with stringValue
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);
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----
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or
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[source,java]
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----
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Optional<String> value = this.getOptionalValue();
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// ...
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if (value.isPresent()) {
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String stringValue = value.get();
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}
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----
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or
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[source,java]
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----
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Optional<String> value = this.getOptionalValue();
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// ...
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String stringValue = value.orElse("default");
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----
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[source,java]
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----
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Optional<String> optional = methodThatReturnsOptional();
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if (optional.isEmpty()) {
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throw new NotFoundException();
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}
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String value = optional.get();
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----
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include::../see.adoc[]
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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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call "xxx.isPresent()" before accessing the value.
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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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