src/java.datatransfer/share/classes/sun/datatransfer/DesktopDatatransferService.java

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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * accompanied this code).
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package sun.datatransfer;

import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.FlavorMap;
import java.util.LinkedHashSet;
import java.util.function.Supplier;

/**
 * Contains services which desktop provides to the datatransfer system to enrich
 * it's functionality.
 *
 * @author Petr Pchelko
 * @since 9
 */
public interface DesktopDatatransferService {

    /**
     * If desktop is present - invokes a {@code Runnable} on the event dispatch
     * thread. Otherwise invokes a {@code run()} method directly.
     *
     * @param  r a {@code Runnable} to invoke
     */
    void invokeOnEventThread(Runnable r);

    /**
     * Get a platform-dependent default unicode encoding to use in datatransfer
     * system.
     *
     * @return default unicode encoding
     */
    String getDefaultUnicodeEncoding();

    /**
     * Takes an appropriate {@code FlavorMap} from the desktop. If no
     * appropriate table is found - uses a provided supplier to instantiate a
     * table. If the desktop is absent - creates and returns a system singleton.
     *
     * @param  supplier a constructor that should be used to create a new
     *         instance of the {@code FlavorMap}
     * @return a {@code FlavorMap}
     */
    FlavorMap getFlavorMap(Supplier<FlavorMap> supplier);

    /**
     * Checks if desktop is present.
     *
     * @return {@code true} is the desktop is present
     */
    boolean isDesktopPresent();

    /**
     * Returns platform-specific mappings for the specified native format. If
     * there are no platform-specific mappings for this native, the method
     * returns an empty {@code Set}.
     *
     * @param  nat a native format to return flavors for
     * @return set of platform-specific mappings for a native format
     */
    LinkedHashSet<DataFlavor> getPlatformMappingsForNative(String nat);

    /**
     * Returns platform-specific mappings for the specified flavor. If there are
     * no platform-specific mappings for this flavor, the method returns an
     * empty {@code Set}.
     *
     * @param  df {@code DataFlavor} to return mappings for
     * @return set of platform-specific mappings for a {@code DataFlavor}
     */
    LinkedHashSet<String> getPlatformMappingsForFlavor(DataFlavor df);

    /**
     * This method is called for text flavor mappings established while parsing
     * the default flavor mappings file. It stores the "eoln" and "terminators"
     * parameters which are not officially part of the MIME type. They are MIME
     * parameters specific to the flavormap.properties file format.
     */
    void registerTextFlavorProperties(String nat, String charset,
                                      String eoln, String terminators);
}