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.
58 lines
2.0 KiB
Plaintext
58 lines
2.0 KiB
Plaintext
== Why is this an issue?
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Calling ``++Class.newInstance++`` invokes the class' default constructor. Unfortunately, since it's not a direct call to the constructor, compile-time checking will be unable to detect the possibility. This means that your code will compile even if you haven't put the invocation in a ``++try++`` block.
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On the other hand, ``++Construtor.newInstance++`` handles exceptions by wrapping them in an ``++InvocationTargetException++`` and explicitly throwing them.
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This rule raises an issue when ``++Class.newInstance++`` is used to invoke a constructor that throws checked exceptions.
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=== Noncompliant code example
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[source,java]
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----
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Foo f = Foo.class.newInstance(); // Noncompliant
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----
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=== Compliant solution
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[source,java]
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----
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Foo f = Foo.class.getConstructor().newInstance();
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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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* Use "xxx.getConstructor().newInstance()" instead.
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=== Highlighting
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``++xxx.newInstance()++``
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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 14 Jul 2016, 18:01:06 Ann Campbell wrote:
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https://github.com/google/error-prone/blob/master/docs/bugpattern/ClassNewInstance.md
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=== on 15 Jul 2016, 09:38:16 Freddy Mallet wrote:
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Hi [~ann.campbell.2], I would convert this "Code Smells Detection Rule" into a "Bugs Detection Rule" by making it raising an issue : IF AND ONLY IF the "class.newInstance()" leads to call a constructor having some checked exceptions. This is another example of the following pattern : instead of enforcing a coding practice allowing to avoid facing some bugs from time to time, let's provide a rule able to precisely detect those bugs.
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=== on 15 Jul 2016, 14:40:14 Freddy Mallet wrote:
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And in that case [~ann.campbell.2], the title and description of the rule should also evolve. For the title, that might become: "'Class.newIntance(...)' should be not be called when the relating nullary constructor throws checked exceptions".
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endif::env-github,rspecator-view[]
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