More options to @DefaultQualifier to adjust default annotations

Please add more options for finer-grained control over which annotations are 
applied to which program elements by default. 

Being able to target annotations at fields without targeting the enclosing 
class as well as only targeting based on a combination of modifiers 
(visibility, static or not, final or not) would add a lot of expressiveness. 
This would be especially useful for classes that hold untrusted data parsed 
from JSON or XML.

This is what the extended @DefaultQualifier API could look like when used in a 
package-info.java file:

@DefaultQualifiers({
  @DefaultQualifier(value = Nullable.class, targets = {
    @Location({ PUBLIC, NON_FINAL, FIELDS }), 
    @Location({ VOLATILE, FIELDS })
  }),
  @DefaultQualifier(value=NonNull.class, targets = {
    @Location({ PUBLIC, STATIC, FINAL, FIELDS })
  })
})
package some.component;

import static checkers.quals.DefaultLocation.*;
import checkers.nullness.quals.NonNull;
import checkers.nullness.quals.Nullable;
import checkers.quals.DefaultQualifier;
import checkers.quals.DefaultQualifiers;
import checkers.quals.Location;

That package-info.java file would override the default annotations to be set 
like this:

class ContrivedExamplePerson {
  public static final String JOB_1 = "koodari"; // @NonNull
  static volatile Boolean isValidationComplete; // @Nullable

  public final String recordType = "minimum";   // not overridden
  public String name;                           // @Nullable
  public String occupation;                     // @Nullable
}

Original issue reported on code.google.com by timo.kin...@gmail.com on 9 Feb 2013 at 1:42

barry-m / checker-framework

More options to @DefaultQualifier to adjust default annotations #205