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https://issues.apache.org/jira/browse/TIKA-1573?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Pavel Micka updated TIKA-1573:
------------------------------
    Description: 
I am facing the following problem. I am using MagicNumber detector, but the 
detection is slow for my purposes, so I have decided to limit the number of 
detected types. However this is not easily possible as: 

 * Mimetypes does not have any remove method.
 * getDefaultMimeTypes method by default load the full set
 * MimeTypes constructor does not accept parameters (mimes with magics)
 * method add is package friendly (so one must construct the wrapper in the 
same package, which is awkward)
 * MimeTypes class is final, so it does not allow to subclass it a improve the 
implementation in object oriented way


My workaround was to force the expected implementation (public add) with 
reflection:
                    Method addMethod = 
decrMimeTypes.getClass().getDeclaredMethod("add", MimeType.class);
                    addMethod.setAccessible(true);
                    addMethod.invoke(myMimeTypes, 
defaultMimeTypes.getRegisteredMimeType(m.toString()));

I can imagine that the current implementation is done this way to be immutable, 
but this can also achieved with parametrized constructor (point 3) with no 
effect on immutability of the class. Or with explicit flag (set by method call) 
that would disallow any further object modifications.

  was:
I am facing the following problem. I am using MagicNumber detector, but the 
detection is slow for my purposes, so I have decided to limit the number of 
detected types. However this is not easily possible as: 

 * Mimetypes does not have any remove method.
 * getDefaultMimeTypes method by default load the full set
 * MimeTypes constructor does not accept parameters (mimes with magics)
 * method add is package friendly (so one must construct the wrapper in the 
same package, which is awkward)
 * MimeTypes class is final, so it does not allow to subclass it a improve the 
implementation in object oriented way


My workaround was to force the expected implementation (public add) with 
reflection:
                    Method addMethod = 
decrMimeTypes.getClass().getDeclaredMethod("add", MimeType.class);
                    addMethod.setAccessible(true); //I am really ashamed to do 
it this way, but the class is final and method package friendly *facepalm*
                    addMethod.invoke(myMimeTypes, 
defaultMimeTypes.getRegisteredMimeType(m.toString()));

I can imagine that the current implementation is done this way to be immutable, 
but this can also achieved with parametrized constructor (point 3) with no 
effect on immutability of the class. Or with explicit flag (set by method call) 
that would disallow any further object modifications.


> Not possible to restrict default mime types
> -------------------------------------------
>
>                 Key: TIKA-1573
>                 URL: https://issues.apache.org/jira/browse/TIKA-1573
>             Project: Tika
>          Issue Type: Improvement
>            Reporter: Pavel Micka
>            Priority: Minor
>              Labels: performance
>
> I am facing the following problem. I am using MagicNumber detector, but the 
> detection is slow for my purposes, so I have decided to limit the number of 
> detected types. However this is not easily possible as: 
>  * Mimetypes does not have any remove method.
>  * getDefaultMimeTypes method by default load the full set
>  * MimeTypes constructor does not accept parameters (mimes with magics)
>  * method add is package friendly (so one must construct the wrapper in the 
> same package, which is awkward)
>  * MimeTypes class is final, so it does not allow to subclass it a improve 
> the implementation in object oriented way
> My workaround was to force the expected implementation (public add) with 
> reflection:
>                     Method addMethod = 
> decrMimeTypes.getClass().getDeclaredMethod("add", MimeType.class);
>                     addMethod.setAccessible(true);
>                     addMethod.invoke(myMimeTypes, 
> defaultMimeTypes.getRegisteredMimeType(m.toString()));
> I can imagine that the current implementation is done this way to be 
> immutable, but this can also achieved with parametrized constructor (point 3) 
> with no effect on immutability of the class. Or with explicit flag (set by 
> method call) that would disallow any further object modifications.



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