What's the difference between AnnotationReader & SimpleAnnotationReader?

Question

The Doctrine Common annotations library defines 2 annotation readers that both implement the Reader interface:

• Doctrine\Common\Annotations\AnnotationReader
• Doctrine\Common\Annotations\SimpleAnnotationReader

Anyone knows the difference between them?

The only hint I have is the docblock on SimpleAnnotationReader:

This annotation reader is intended to be used in projects where you have full-control over all annotations that are available.

Answer 1

• The AnnotationReader will try to read ALL annotations.

You can give it a list of excluded annotations like @param and @return to ignore. It can be a problem since it's hard to exclude any possible annotation that you don't want.

• The SimpleAnnotationReader can load only the annotations you register to it.

Code example:

AnnotationRegistry::registerAutoloadNamespace('My\Annotation', 'dir/');
$this->annotationReader = new SimpleAnnotationReader();
$this->annotationReader->addNamespace('My\Annotation');

I will not get errors if there is any unknown annotation in the file.

There's one catch though: if the user makes a typo in the annotation name, then the reader will silently ignore it :(

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Source: while developing PHP-DI, I tested both. The SimpleAnnotationReader is better for me because I want it to only read my @Inject annotation. When using AnnotationReader, I got errors if there was any unknown annotation in the file (for example @expectedException from PHPUnit).

See also this issue.