Class MimeUtil

java.lang.Object
eu.medsea.mimeutil.MimeUtil

public class MimeUtil extends Object

NOTE: Since version 2.1 this class delegates ALL calls to a static instance of the new MimeUtil2 implementation.

See Also:
  • Constructor Details

    • MimeUtil

      public MimeUtil()
  • Method Details

    • addKnownMimeType

      public static void addKnownMimeType(MimeType mimeType)
      While MimeType(s) are being loaded by the MimeDetector(s) they should be added to the list of known MIME types. It is not mandatory for MimeDetector(s) to do so but they should where possible so that the list is as complete as possible. You can add other MIME types to this list using this method. You can then use the isMimeTypeKnown(...) utility methods to see if a MIME type you have matches one that the utility has already seen.

      This can be used to limit the mime types you work with i.e. if its not been loaded then don't bother using it as it won't match. This is no guarantee that a match will not be found as it is possible that a particular MimeDetector does not have an initialisation phase that loads all of the MIME types it will match.

      For instance if you had a MIME type of abc/xyz and passed this to isMimeTypeKnown(...) it would return false unless you specifically add this to the know MIME types using this method.

      Parameters:
      mimeType - a MIME type you want to add to the known MIME types. Duplicates are ignored.
      See Also:
    • addKnownMimeType

      public static void addKnownMimeType(String mimeType)
      While MimeType(s) are being loaded by the MimeDetector(s) they should be added to the list of known MIME types. It is not mandatory for MimeDetector(s) to do so but they should where possible so that the list is as complete as possible. You can add other MIME types to this list using this method. You can then use the isMimeTypeKnown(...) utility methods to see if a MIME type you have matches one that the utility has already seen.

      This can be used to limit the mime types you work with i.e. if its not been loaded then don't bother using it as it won't match. This is no guarantee that a match will not be found as it is possible that a particular MimeDetector does not have an initialisation phase that loads all of the MIME types it will match.

      For instance if you had a MIME type of abc/xyz and passed this to isMimeTypeKnown(...) it would return false unless you specifically add this to the know MIME types using this method.

      Parameters:
      mimeType - a MIME type you want to add to the known MIME types. Duplicates are ignored.
      See Also:
    • registerMimeDetector

      public static MimeDetector registerMimeDetector(String mimeDetector)
      Register a MimeDetector and add it to the MimeDetector registry. MimeDetector(s) are effectively singletons as they are keyed against their fully qualified class name.
      Parameters:
      mimeDetector - . This must be the fully qualified name of a concrete instance of an AbstractMimeDetector class. This enforces that all custom MimeDetector(s) extend the AbstractMimeDetector.
      See Also:
    • getExtension

      public static String getExtension(File file)
      Get the extension part of a file name defined by the file parameter.
      Parameters:
      file - a file object
      Returns:
      the file extension or null if it does not have one.
    • getExtension

      public static String getExtension(String fileName)
      Get the extension part of a file name defined by the fileName parameter. There may be no extension or it could be a single part extension such as .bat or a multi-part extension such as .tar.gz
      Parameters:
      fileName - a relative or absolute path to a file
      Returns:
      the file extension or null if it does not have one.
    • getFirstMimeType

      public static MimeType getFirstMimeType(String mimeTypes)
      Get the first in a comma separated list of mime types. Useful when using extension mapping that can return multiple mime types separate by commas and you only want the first one.
      Parameters:
      mimeTypes - comma separated list of mime types
      Returns:
      first in a comma separated list of mime types or null if the mimeTypes string is null or empty
    • getMediaType

      public static String getMediaType(String mimeType) throws MimeException
      Utility method to get the major or media part of a mime type i.e. the part before the '/' character
      Parameters:
      mimeType - you want to get the media part from
      Returns:
      media type of the mime type
      Throws:
      MimeException - if you pass in an invalid mime type structure
    • getMimeQuality

      public static double getMimeQuality(String mimeType) throws MimeException
      Utility method to get the quality part of a mime type. If it does not exist then it is always set to q=1.0 unless it's a wild card. For the major component wild card the value is set to 0.01 For the minor component wild card the value is set to 0.02

      Thanks to the Apache organisation for these settings.

      Parameters:
      mimeType - a valid mime type string with or without a valid q parameter
      Returns:
      the quality value of the mime type either calculated from the rules above or the actual value defined.
      Throws:
      MimeException - this is thrown if the mime type pattern is invalid.
    • getMimeDetector

      public static MimeDetector getMimeDetector(String name)
      Get a registered MimeDetector by name.
      Parameters:
      name - the name of a registered MimeDetector. This is always the fully qualified name of the class implementing the MimeDetector.
      Returns:
    • getMimeTypes

      public static final Collection getMimeTypes(byte[] data) throws MimeException
      Get a Collection of possible MimeType(s) that this byte array could represent according to the registered MimeDetector(s). If no MimeType(s) are detected then the returned Collection will contain only the UNKNOWN_MIME_TYPE
      Parameters:
      data -
      Returns:
      all matching MimeType(s)
      Throws:
      MimeException
    • getMimeTypes

      public static final Collection getMimeTypes(byte[] data, MimeType unknownMimeType) throws MimeException
      Get a Collection of possible MimeType(s) that this byte array could represent according to the registered MimeDetector(s). If no MimeType(s) are detected then the returned Collection will contain only the passed in unknownMimeType
      Parameters:
      data -
      unknownMimeType - used if the registered MimeDetector(s) fail to match any MimeType(s)
      Returns:
      all matching MimeType(s)
      Throws:
      MimeException
    • getMimeTypes

      public static final Collection getMimeTypes(File file) throws MimeException
      Get all of the matching mime types for this file object. The method delegates down to each of the registered MimeHandler(s) and returns a normalised list of all matching mime types. If no matching mime types are found the returned Collection will contain the default UNKNOWN_MIME_TYPE
      Parameters:
      file - the File object to detect.
      Returns:
      collection of matching MimeType(s)
      Throws:
      MimeException - if there are problems such as reading files generated when the MimeHandler(s) executed.
    • getMimeTypes

      public static final Collection getMimeTypes(File file, MimeType unknownMimeType) throws MimeException
      Get all of the matching mime types for this file object. The method delegates down to each of the registered MimeHandler(s) and returns a normalised list of all matching mime types. If no matching mime types are found the returned Collection will contain the unknownMimeType passed in.
      Parameters:
      file - the File object to detect.
      unknownMimeType - .
      Returns:
      the Collection of matching mime types. If the collection would be empty i.e. no matches then this will contain the passed in parameter unknownMimeType
      Throws:
      MimeException - if there are problems such as reading files generated when the MimeHandler(s) executed.
    • getMimeTypes

      public static final Collection getMimeTypes(InputStream in) throws MimeException
      Get all of the matching mime types for this InputStream object. The method delegates down to each of the registered MimeHandler(s) and returns a normalised list of all matching mime types. If no matching mime types are found the returned Collection will contain the default UNKNOWN_MIME_TYPE
      Parameters:
      in - InputStream to detect.
      Returns:
      Throws:
      MimeException - if there are problems such as reading files generated when the MimeHandler(s) executed.
    • getMimeTypes

      public static final Collection getMimeTypes(InputStream in, MimeType unknownMimeType) throws MimeException
      Get all of the matching mime types for this InputStream object. The method delegates down to each of the registered MimeHandler(s) and returns a normalised list of all matching mime types. If no matching mime types are found the returned Collection will contain the unknownMimeType passed in.
      Parameters:
      in - the InputStream object to detect.
      unknownMimeType - .
      Returns:
      the Collection of matching mime types. If the collection would be empty i.e. no matches then this will contain the passed in parameter unknownMimeType
      Throws:
      MimeException - if there are problems such as reading files generated when the MimeHandler(s) executed.
    • getMimeTypes

      public static final Collection getMimeTypes(String fileName) throws MimeException
      Get all of the matching mime types for this file name. The method delegates down to each of the registered MimeHandler(s) and returns a normalised list of all matching mime types. If no matching mime types are found the returned Collection will contain the default UNKNOWN_MIME_TYPE
      Parameters:
      fileName - the name of a file to detect.
      Returns:
      collection of matching MimeType(s)
      Throws:
      MimeException - if there are problems such as reading files generated when the MimeHandler(s) executed.
    • getMimeTypes

      public static final Collection getMimeTypes(String fileName, MimeType unknownMimeType) throws MimeException
      Get all of the matching mime types for this file name . The method delegates down to each of the registered MimeHandler(s) and returns a normalised list of all matching mime types. If no matching mime types are found the returned Collection will contain the unknownMimeType passed in.
      Parameters:
      fileName - the name of a file to detect.
      unknownMimeType - .
      Returns:
      the Collection of matching mime types. If the collection would be empty i.e. no matches then this will contain the passed in parameter unknownMimeType
      Throws:
      MimeException - if there are problems such as reading files generated when the MimeHandler(s) executed.
    • getMimeTypes

      public static final Collection getMimeTypes(URL url) throws MimeException
      Get all of the matching mime types for this URL object. The method delegates down to each of the registered MimeHandler(s) and returns a normalised list of all matching mime types. If no matching mime types are found the returned Collection will contain the default UNKNOWN_MIME_TYPE
      Parameters:
      url - a URL to detect.
      Returns:
      Collection of matching MimeType(s)
      Throws:
      MimeException - if there are problems such as reading files generated when the MimeHandler(s) executed.
    • getMimeTypes

      public static final Collection getMimeTypes(URL url, MimeType unknownMimeType) throws MimeException
      Throws:
      MimeException
    • getNativeOrder

      public static ByteOrder getNativeOrder()
      Get the native byte order of the OS on which you are running. It will be either big or little endian. This is used internally for the magic mime rules mapping.
      Returns:
      ByteOrder
    • getPreferedMimeType

      public static MimeType getPreferedMimeType(String accept, String canProvide)
      Gives you the best match for your requirements.

      You can pass the accept header from a browser request to this method along with a comma separated list of possible mime types returned from say getExtensionMimeTypes(...) and the best match according to the accept header will be returned.

      The following is typical of what may be specified in an HTTP Accept header:

      Accept: text/xml, application/xml, application/xhtml+xml, text/html;q=0.9, text/plain;q=0.8, video/x-mng, image/png, image/jpeg, image/gif;q=0.2, text/css, */*;q=0.1

      The quality parameter (q) indicates how well the user agent handles the MIME type. A value of 1 indicates the MIME type is understood perfectly, and a value of 0 indicates the MIME type isn't understood at all.

      The reason the image/gif MIME type contains a quality parameter of 0.2, is to indicate that PNG invalid input: '&' JPEG are preferred over GIF if the server is using content negotiation to deliver either a PNG or a GIF to user agents. Similarly, the text/html quality parameter has been lowered a little, to ensure that the XML MIME types are given in preference if content negotiation is being used to serve an XHTML document.

      Parameters:
      accept - is a comma separated list of mime types you can accept including QoS parameters. Can pass the Accept: header directly.
      canProvide - is a comma separated list of mime types that can be provided such as that returned from a call to getExtensionMimeTypes(...)
      Returns:
      the best matching mime type possible.
    • getMostSpecificMimeType

      public static MimeType getMostSpecificMimeType(Collection mimeTypes)
      Get the most specific match of the Collection of mime types passed in. The Collection
      Parameters:
      mimeTypes - this should be the Collection of mime types returned from a getMimeTypes(...) call.
      Returns:
      the most specific MimeType. If more than one of the mime types in the Collection have the same value then the first one found with this value in the Collection is returned.
    • getSubType

      public static String getSubType(String mimeType) throws MimeException
      Utility method to get the minor part of a mime type i.e. the bit after the '/' character
      Parameters:
      mimeType - you want to get the minor part from
      Returns:
      sub type of the mime type
      Throws:
      MimeException - if you pass in an invalid mime type structure
    • isMimeTypeKnown

      public static boolean isMimeTypeKnown(MimeType mimeType)
      Check to see if this mime type is one of the types seen during initialisation or has been added at some later stage using addKnownMimeType(...)
      Parameters:
      mimeType -
      Returns:
      true if the mimeType is in the list else false is returned
      See Also:
    • isMimeTypeKnown

      public static boolean isMimeTypeKnown(String mimeType)
      Check to see if this mime type is one of the types seen during initialisation or has been added at some later stage using addKnownMimeType(...)
      Parameters:
      mimeType -
      Returns:
      true if the mimeType is in the list else false is returned
      See Also:
    • isTextMimeType

      public static boolean isTextMimeType(MimeType mimeType)
      Utility convenience method to check if a particular MimeType instance is actually a TextMimeType. Used when iterating over a collection of MimeType's to help with casting to enable access the the TextMimeType methods not available to a standard MimeType. Can also use instanceof.
      Parameters:
      mimeType -
      Returns:
      true if the passed in instance is a TextMimeType
      See Also:
    • unregisterMimeDetector

      public static MimeDetector unregisterMimeDetector(MimeDetector mimeDetector)
      Remove a previously registered MimeDetector
      Parameters:
      mimeDetector -
      Returns:
      the MimeDetector that was removed from the registry else null.
    • unregisterMimeDetector

      public static MimeDetector unregisterMimeDetector(String mimeDetector)
      Remove a previously registered MimeDetector
      Parameters:
      mimeDetector -
      Returns:
      the MimeDetector that was removed from the registry else null.
    • getQuality

      public static double getQuality(String mimeType) throws MimeException
      Get the quality parameter of this mime type i.e. the q= property. This method implements a value system similar to that used by the apache server i.e. if the media type is a * then it's q value is set to 0.01 and if the sub type is a * then the q value is set to 0.02 unless a specific q value is specified. If a q property is set it is limited to a max value of 1.0
      Parameters:
      mimeType -
      Returns:
      the quality value as a double between 0.0 and 1.0
      Throws:
      MimeException
    • getInputStreamForURL

      public static InputStream getInputStreamForURL(URL url) throws Exception
      Utility method to get the InputStream from a URL. Handles several schemes, for instance, if the URL points to a jar entry it will get a proper usable stream from the URL
      Parameters:
      url -
      Returns:
      Throws:
      Exception