java.awt.datatransfer

## Class SystemFlavorMap

- java.lang.Object
- - java.awt.datatransfer.SystemFlavorMap

- All Implemented Interfaces:
    FlavorMap, FlavorTable

      public final class SystemFlavorMap
      extends Object
      implements FlavorMap, FlavorTable

  The SystemFlavorMap is a configurable map between "natives" (Strings), which correspond to platform-specific data formats, and "flavors" (DataFlavors), which correspond to platform-independent MIME types. This mapping is used by the data transfer subsystem to transfer data between Java and native applications, and between Java applications in separate VMs.

  Since:
    1.2

- - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `addFlavorForUnencodedNative(String nat, DataFlavor flav)` | Adds a mapping from a single `String` native to a single `DataFlavor`.
    `void` | `addUnencodedNativeForFlavor(DataFlavor flav, String nat)` | Adds a mapping from the specified `DataFlavor` (and all `DataFlavor`s equal to the specified `DataFlavor`) to the specified `String` native.
    `static DataFlavor` | `decodeDataFlavor(String nat)` | Decodes a `String` native for use as a `DataFlavor`.
    `static String` | `decodeJavaMIMEType(String nat)` | Decodes a `String` native for use as a Java MIME type.
    `static String` | `encodeDataFlavor(DataFlavor flav)` | Encodes a `DataFlavor` for use as a `String` native.
    `static String` | `encodeJavaMIMEType(String mimeType)` | Encodes a MIME type for use as a `String` native.
    `static FlavorMap` | `getDefaultFlavorMap()` | Returns the default FlavorMap for this thread's ClassLoader.
    `List<DataFlavor>` | `getFlavorsForNative(String nat)` | Returns a `List` of `DataFlavor`s to which the specified `String` native can be translated by the data transfer subsystem.
    `Map<String,DataFlavor>` | `getFlavorsForNatives(String[] natives)` | Returns a `Map` of the specified `String` natives to their most preferred `DataFlavor`.
    `List<String>` | `getNativesForFlavor(DataFlavor flav)` | Returns a `List` of `String` natives to which the specified `DataFlavor` can be translated by the data transfer subsystem.
    `Map<DataFlavor,String>` | `getNativesForFlavors(DataFlavor[] flavors)` | Returns a `Map` of the specified `DataFlavor`s to their most preferred `String` native.
    `static boolean` | `isJavaMIMEType(String str)` | Returns whether the specified `String` is an encoded Java MIME type.
    `void` | `setFlavorsForNative(String nat, DataFlavor[] flavors)` | Discards the current mappings for the specified `String` native, and creates new mappings to the specified `DataFlavor`s.
    `void` | `setNativesForFlavor(DataFlavor flav, String[] natives)` | Discards the current mappings for the specified `DataFlavor` and all `DataFlavor`s equal to the specified `DataFlavor`, and creates new mappings to the specified `String` natives.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Method Detail

    - #### getDefaultFlavorMap

          public static FlavorMap getDefaultFlavorMap()

      Returns the default FlavorMap for this thread's ClassLoader.

    - #### getNativesForFlavor

          public List<String> getNativesForFlavor(DataFlavor flav)

      Returns a `List` of `String` natives to which the specified `DataFlavor` can be translated by the data transfer subsystem. The `List` will be sorted from best native to worst. That is, the first native will best reflect data in the specified flavor to the underlying native platform.

      If the specified `DataFlavor` is previously unknown to the data transfer subsystem and the data transfer subsystem is unable to translate this `DataFlavor` to any existing native, then invoking this method will establish a mapping in both directions between the specified `DataFlavor` and an encoded version of its MIME type as its native.

      Specified by:
        `getNativesForFlavor` in interface `FlavorTable`
      Parameters:
        `flav` - the `DataFlavor` whose corresponding natives should be returned. If `null` is specified, all natives currently known to the data transfer subsystem are returned in a non-deterministic order.
      Returns:
        a `java.util.List` of `java.lang.String` objects which are platform-specific representations of platform- specific data formats
      Since:
        1.4
      See Also:
        `encodeDataFlavor(java.awt.datatransfer.DataFlavor)`

    - #### getFlavorsForNative

          public List<DataFlavor> getFlavorsForNative(String nat)

      Returns a `List` of `DataFlavor`s to which the specified `String` native can be translated by the data transfer subsystem. The `List` will be sorted from best `DataFlavor` to worst. That is, the first `DataFlavor` will best reflect data in the specified native to a Java application.

      If the specified native is previously unknown to the data transfer subsystem, and that native has been properly encoded, then invoking this method will establish a mapping in both directions between the specified native and a `DataFlavor` whose MIME type is a decoded version of the native.

      If the specified native is not a properly encoded native and the mappings for this native have not been altered with `setFlavorsForNative`, then the contents of the `List` is platform dependent, but `null` cannot be returned.

      Specified by:
        `getFlavorsForNative` in interface `FlavorTable`
      Parameters:
        `nat` - the native whose corresponding `DataFlavor`s should be returned. If `null` is specified, all `DataFlavor`s currently known to the data transfer subsystem are returned in a non-deterministic order.
      Returns:
        a `java.util.List` of `DataFlavor` objects into which platform-specific data in the specified, platform-specific native can be translated
      Since:
        1.4
      See Also:
        `encodeJavaMIMEType(java.lang.String)`

    - #### getNativesForFlavors

          public Map<DataFlavor,String> getNativesForFlavors(DataFlavor[] flavors)

      Returns a `Map` of the specified `DataFlavor`s to their most preferred `String` native. Each native value will be the same as the first native in the List returned by `getNativesForFlavor` for the specified flavor.

      If a specified `DataFlavor` is previously unknown to the data transfer subsystem, then invoking this method will establish a mapping in both directions between the specified `DataFlavor` and an encoded version of its MIME type as its native.

      Specified by:
        `getNativesForFlavors` in interface `FlavorMap`
      Parameters:
        `flavors` - an array of `DataFlavor`s which will be the key set of the returned `Map`. If `null` is specified, a mapping of all `DataFlavor`s known to the data transfer subsystem to their most preferred `String` natives will be returned.
      Returns:
        a `java.util.Map` of `DataFlavor`s to `String` natives
      See Also:
        `getNativesForFlavor(java.awt.datatransfer.DataFlavor)`, `encodeDataFlavor(java.awt.datatransfer.DataFlavor)`

    - #### getFlavorsForNatives

          public Map<String,DataFlavor> getFlavorsForNatives(String[] natives)

      Returns a `Map` of the specified `String` natives to their most preferred `DataFlavor`. Each `DataFlavor` value will be the same as the first `DataFlavor` in the List returned by `getFlavorsForNative` for the specified native.

      If a specified native is previously unknown to the data transfer subsystem, and that native has been properly encoded, then invoking this method will establish a mapping in both directions between the specified native and a `DataFlavor` whose MIME type is a decoded version of the native.

      Specified by:
        `getFlavorsForNatives` in interface `FlavorMap`
      Parameters:
        `natives` - an array of `String`s which will be the key set of the returned `Map`. If `null` is specified, a mapping of all supported `String` natives to their most preferred `DataFlavor`s will be returned.
      Returns:
        a `java.util.Map` of `String` natives to `DataFlavor`s
      See Also:
        `getFlavorsForNative(java.lang.String)`, `encodeJavaMIMEType(java.lang.String)`

    - #### addUnencodedNativeForFlavor

          public void addUnencodedNativeForFlavor(DataFlavor flav,
                                                  String nat)

      Adds a mapping from the specified `DataFlavor` (and all `DataFlavor`s equal to the specified `DataFlavor`) to the specified `String` native. Unlike `getNativesForFlavor`, the mapping will only be established in one direction, and the native will not be encoded. To establish a two-way mapping, call `addFlavorForUnencodedNative` as well. The new mapping will be of lower priority than any existing mapping. This method has no effect if a mapping from the specified or equal `DataFlavor` to the specified `String` native already exists.
      Parameters:
        `flav` - the `DataFlavor` key for the mapping
        `nat` - the `String` native value for the mapping
      Throws:
        `NullPointerException` - if flav or nat is `null`
      Since:
        1.4
      See Also:
        `addFlavorForUnencodedNative(java.lang.String, java.awt.datatransfer.DataFlavor)`

    - #### setNativesForFlavor

          public void setNativesForFlavor(DataFlavor flav,
                                          String[] natives)

      Discards the current mappings for the specified `DataFlavor` and all `DataFlavor`s equal to the specified `DataFlavor`, and creates new mappings to the specified `String` natives. Unlike `getNativesForFlavor`, the mappings will only be established in one direction, and the natives will not be encoded. To establish two-way mappings, call `setFlavorsForNative` as well. The first native in the array will represent the highest priority mapping. Subsequent natives will represent mappings of decreasing priority.

      If the array contains several elements that reference equal `String` natives, this method will establish new mappings for the first of those elements and ignore the rest of them.

      It is recommended that client code not reset mappings established by the data transfer subsystem. This method should only be used for application-level mappings.

      Parameters:
        `flav` - the `DataFlavor` key for the mappings
        `natives` - the `String` native values for the mappings
      Throws:
        `NullPointerException` - if flav or natives is `null` or if natives contains `null` elements
      Since:
        1.4
      See Also:
        `setFlavorsForNative(java.lang.String, java.awt.datatransfer.DataFlavor[])`

    - #### addFlavorForUnencodedNative

          public void addFlavorForUnencodedNative(String nat,
                                                  DataFlavor flav)

      Adds a mapping from a single `String` native to a single `DataFlavor`. Unlike `getFlavorsForNative`, the mapping will only be established in one direction, and the native will not be encoded. To establish a two-way mapping, call `addUnencodedNativeForFlavor` as well. The new mapping will be of lower priority than any existing mapping. This method has no effect if a mapping from the specified `String` native to the specified or equal `DataFlavor` already exists.
      Parameters:
        `nat` - the `String` native key for the mapping
        `flav` - the `DataFlavor` value for the mapping
      Throws:
        `NullPointerException` - if nat or flav is `null`
      Since:
        1.4
      See Also:
        `addUnencodedNativeForFlavor(java.awt.datatransfer.DataFlavor, java.lang.String)`

    - #### setFlavorsForNative

          public void setFlavorsForNative(String nat,
                                          DataFlavor[] flavors)

      Discards the current mappings for the specified `String` native, and creates new mappings to the specified `DataFlavor`s. Unlike `getFlavorsForNative`, the mappings will only be established in one direction, and the natives need not be encoded. To establish two-way mappings, call `setNativesForFlavor` as well. The first `DataFlavor` in the array will represent the highest priority mapping. Subsequent `DataFlavor`s will represent mappings of decreasing priority.

      If the array contains several elements that reference equal `DataFlavor`s, this method will establish new mappings for the first of those elements and ignore the rest of them.

      It is recommended that client code not reset mappings established by the data transfer subsystem. This method should only be used for application-level mappings.

      Parameters:
        `nat` - the `String` native key for the mappings
        `flavors` - the `DataFlavor` values for the mappings
      Throws:
        `NullPointerException` - if nat or flavors is `null` or if flavors contains `null` elements
      Since:
        1.4
      See Also:
        `setNativesForFlavor(java.awt.datatransfer.DataFlavor, java.lang.String[])`

    - #### encodeJavaMIMEType

          public static String encodeJavaMIMEType(String mimeType)

      Encodes a MIME type for use as a `String` native. The format of an encoded representation of a MIME type is implementation-dependent. The only restrictions are:
      - The encoded representation is `null` if and only if the MIME type `String` is `null`.
      - The encoded representations for two non-`null` MIME type `String`s are equal if and only if these `String`s are equal according to `String.equals(Object)`.

      The reference implementation of this method returns the specified MIME type `String` prefixed with `JAVA_DATAFLAVOR:`.

      Parameters:
        `mimeType` - the MIME type to encode
      Returns:
        the encoded `String`, or `null` if mimeType is `null`

    - #### encodeDataFlavor

          public static String encodeDataFlavor(DataFlavor flav)

      Encodes a `DataFlavor` for use as a `String` native. The format of an encoded `DataFlavor` is implementation-dependent. The only restrictions are:
      - The encoded representation is `null` if and only if the specified `DataFlavor` is `null` or its MIME type `String` is `null`.
      - The encoded representations for two non-`null` `DataFlavor`s with non-`null` MIME type `String`s are equal if and only if the MIME type `String`s of these `DataFlavor`s are equal according to `String.equals(Object)`.

      The reference implementation of this method returns the MIME type `String` of the specified `DataFlavor` prefixed with `JAVA_DATAFLAVOR:`.

      Parameters:
        `flav` - the `DataFlavor` to encode
      Returns:
        the encoded `String`, or `null` if flav is `null` or has a `null` MIME type

    - #### isJavaMIMEType

          public static boolean isJavaMIMEType(String str)

      Returns whether the specified `String` is an encoded Java MIME type.
      Parameters:
        `str` - the `String` to test
      Returns:
        `true` if the `String` is encoded; `false` otherwise

    - #### decodeJavaMIMEType

          public static String decodeJavaMIMEType(String nat)

      Decodes a `String` native for use as a Java MIME type.
      Parameters:
        `nat` - the `String` to decode
      Returns:
        the decoded Java MIME type, or `null` if nat is not an encoded `String` native

    - #### decodeDataFlavor

          public static DataFlavor decodeDataFlavor(String nat)
                                             throws ClassNotFoundException

      Decodes a `String` native for use as a `DataFlavor`.
      Parameters:
        `nat` - the `String` to decode
      Returns:
        the decoded `DataFlavor`, or `null` if nat is not an encoded `String` native
      Throws:
        `ClassNotFoundException`

Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2026, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.