Class Clipboard

  • Direct Known Subclasses:
    Dragboard

    public class Clipboard
    extends Object
    Represents an operating system clipboard, on which data may be placed during, for example, cut, copy, and paste operations.

    To access the general system clipboard, use the following code:

    
         Clipboard clipboard = Clipboard.getSystemClipboard();
     

    There is only ever one instance of the system clipboard in the application, so it is perfectly acceptable to stash a reference to it somewhere handy if you so choose.

    The Clipboard operates on the concept of having a single conceptual item on the clipboard at any one time -- though it may be placed on the clipboard in different formats. For example, the user might select text in an HTML editor and press the ctrl+c or cmd+c to copy it. In this case, the same text might be available on the clipboard both as HTML and as plain text. There are two copies of the data on the clipboard, but they both represent the same data.

    Content is specified on the Clipboard by using the setContent(java.util.Map<javafx.scene.input.DataFormat, java.lang.Object>) method. First, construct a ClipboardContent object, then invoke setContent. Every time setContent is called, any previous data on the clipboard is cleared and replaced with this new content.

    
         final Clipboard clipboard = Clipboard.getSystemClipboard();
         final ClipboardContent content = new ClipboardContent();
         content.putString("Some text");
         content.putHtml("<b>Some</b> text");
         clipboard.setContent(content);
     

    The ClipboardContent class is simply a map with convenience methods for dealing with common data types added to a clipboard.

    Because multiple representations of the same data may exist on the clipboard, and because different applications have different capabilities for handling different content types, it is important to place as many data representations on the clipboard as is practical to facilitate external applications. Note that sometimes the operating system might be helpful in some cases and add multiple types for you. For example, the Mac might set the plain text string for you when you specify the RTF type. How and under what circumstances this occurs is outside the realm of this specification, consult your OS documentation.

    When reading data off the clipboard, it is important to look for the richest supported type first. For example, if I have a text document which supports embedding of images and media formats, when pasting content from the clipboard I should first check to see if the content can be represented as media or as an image. If not, then I might check for RTF or HTML or whatever rich text format is supported by my document type. If not, then I might just take a String.

    Or for example, if I have a plain text document, then I would simple get a String representation and use that, if available. I can check to see if the clipboard "hasHtml" or "hasString".

    
         if (clipboard.hasString()) { ... }
     

    In addition to the common or built in types, you may put any arbitrary data onto the clipboard (assuming it is serializable).

    Content types are defined by the DataFormat objects. The DataFormat class defines an immutable object, and there are a number of static final fields for common DataFormat types. Of course application specific DataFormat types can also be declared and used. The following two methods are equivalent (and the second call will override the first!)

    
         ClipboardContent content = new ClipboardContent();
         content.putString("some text");
         content.put(DataFormat.PLAIN_TEXT, "other text");
     

    On embedded platforms that do not have their own windowing system, the Clipboard returned from Clipboard.getSystemClipboard() might not be accessible from outside the JavaFX application.

    If a security manager is present, the application must have the FXPermission "accessClipboard" in order for the Clipboard returned from Clipboard.getSystemClipboard() to be accessible from outside the JavaFX application. For compatibility with previous versions of the JDK the equivalent AWTPermission "accessClipboard" will also allow the FX clipboard to be accessible from outside the JavaFX application.

    If the application lacks permission or if the platform doesn't support a shared clipboard, the clipboard returned by Clipboard.getSystemClipboard() can be used for exchange of data between different parts of one JavaFX application but cannot be used to exchange data between multiple applications.

    Since:
    JavaFX 2.0
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void clear()
      Clears the clipboard of any and all content.
      Object getContent​(DataFormat dataFormat)
      Returns the content stored in this clipboard of the given type, or null if there is no content with this type.
      Set<DataFormat> getContentTypes()
      Gets the set of DataFormat types on this Clipboard instance which have associated data registered on the clipboard.
      List<File> getFiles()
      Gets the List of Files from the clipboard which had previously been registered.
      String getHtml()
      Gets the HTML text String from the clipboard which had previously been registered.
      Image getImage()
      Gets the Image from the clipboard which had previously been registered.
      String getRtf()
      Gets the RTF text String from the clipboard which had previously been registered.
      String getString()
      Gets the plain text String from the clipboard which had previously been registered.
      static Clipboard getSystemClipboard()
      Gets the current system clipboard, through which data can be stored and retrieved.
      String getUrl()
      Gets the URL String from the clipboard which had previously been registered.
      boolean hasContent​(DataFormat dataFormat)
      Tests whether there is any content on this clipboard of the given DataFormat type.
      boolean hasFiles()
      Gets whether an List of Files (DataFormat.FILES) has been registered on this Clipboard.
      boolean hasHtml()
      Gets whether an HTML text String (DataFormat.HTML) has been registered on this Clipboard.
      boolean hasImage()
      Gets whether an Image (DataFormat.IMAGE) has been registered on this Clipboard.
      boolean hasRtf()
      Gets whether an RTF String (DataFormat.RTF) has been registered on this Clipboard.
      boolean hasString()
      Gets whether a plain text String (DataFormat.PLAIN_TEXT) has been registered on this Clipboard.
      boolean hasUrl()
      Gets whether a url String (DataFormat.URL) has been registered on this Clipboard.
      boolean setContent​(Map<DataFormat,​Object> content)
      Puts content onto the clipboard.
    • Method Detail

      • getSystemClipboard

        public static Clipboard getSystemClipboard()
        Gets the current system clipboard, through which data can be stored and retrieved. There is ever only one system clipboard for a JavaFX application.
        Returns:
        The single system clipboard, used for cut / copy / paste operations
      • clear

        public final void clear()
        Clears the clipboard of any and all content. Any subsequent call to getContentTypes() before putting more content on the clipboard will result in an empty set being returned.
      • getContentTypes

        public final Set<DataFormat> getContentTypes()
        Gets the set of DataFormat types on this Clipboard instance which have associated data registered on the clipboard. This set will always be non-null and immutable. If the Clipboard is subsequently modifed, this returned set is not updated.
        Returns:
        A non-null immutable set of content types.
      • setContent

        public final boolean setContent​(Map<DataFormat,​Object> content)
        Puts content onto the clipboard. This call will always result in clearing all previous content from the clipboard, and replacing it with whatever content is specified in the supplied ClipboardContent map.
        Parameters:
        content - The content to put on the clipboard. If null, the clipboard is simply cleared and no new content added.
        Returns:
        True if successful, false if the content fails to be added.
        Throws:
        NullPointerException - if null data reference is passed for any format
      • getContent

        public final Object getContent​(DataFormat dataFormat)
        Returns the content stored in this clipboard of the given type, or null if there is no content with this type.
        Parameters:
        dataFormat - the format type
        Returns:
        The content associated with this type, or null if there is none
      • hasContent

        public final boolean hasContent​(DataFormat dataFormat)
        Tests whether there is any content on this clipboard of the given DataFormat type.
        Parameters:
        dataFormat - the format type
        Returns:
        true if there is content on this clipboard for this type
      • hasString

        public final boolean hasString()
        Gets whether a plain text String (DataFormat.PLAIN_TEXT) has been registered on this Clipboard.
        Returns:
        true if hasContent(DataFormat.PLAIN_TEXT) returns true, false otherwise
      • getString

        public final String getString()
        Gets the plain text String from the clipboard which had previously been registered. This is equivalent to invoking getContent(DataFormat.PLAIN_TEXT). If no such entry exists, null is returned.
        Returns:
        The String on the clipboard associated with DataFormat.PLAIN_TEXT, or null if there is not one.
      • hasUrl

        public final boolean hasUrl()
        Gets whether a url String (DataFormat.URL) has been registered on this Clipboard.
        Returns:
        true if hasContent(DataFormat.URL) returns true, false otherwise
      • getUrl

        public final String getUrl()
        Gets the URL String from the clipboard which had previously been registered. This is equivalent to invoking getContent(DataFormat.URL). If no such entry exists, null is returned.
        Returns:
        The String on the clipboard associated with DataFormat.URL, or null if there is not one.
      • hasHtml

        public final boolean hasHtml()
        Gets whether an HTML text String (DataFormat.HTML) has been registered on this Clipboard.
        Returns:
        true if hasContent(DataFormat.HTML) returns true, false otherwise
      • getHtml

        public final String getHtml()
        Gets the HTML text String from the clipboard which had previously been registered. This is equivalent to invoking getContent(DataFormat.HTML). If no such entry exists, null is returned.
        Returns:
        The String on the clipboard associated with DataFormat.HTML, or null if there is not one.
      • hasRtf

        public final boolean hasRtf()
        Gets whether an RTF String (DataFormat.RTF) has been registered on this Clipboard.
        Returns:
        true if hasContent(DataFormat.RTF) returns true, false otherwise
      • getRtf

        public final String getRtf()
        Gets the RTF text String from the clipboard which had previously been registered. This is equivalent to invoking getContent(DataFormat.RTF). If no such entry exists, null is returned.
        Returns:
        The String on the clipboard associated with DataFormat.RTF, or null if there is not one.
      • hasImage

        public final boolean hasImage()
        Gets whether an Image (DataFormat.IMAGE) has been registered on this Clipboard.
        Returns:
        true if hasContent(DataFormat.IMAGE) returns true, false otherwise
      • getImage

        public final Image getImage()
        Gets the Image from the clipboard which had previously been registered. This is equivalent to invoking getContent(DataFormat.IMAGE). If no such entry exists, null is returned.
        Returns:
        The Image on the clipboard associated with DataFormat.IMAGE, or null if there is not one.
      • hasFiles

        public final boolean hasFiles()
        Gets whether an List of Files (DataFormat.FILES) has been registered on this Clipboard.
        Returns:
        true if hasContent(DataFormat.FILES) returns true, false otherwise
      • getFiles

        public final List<File> getFiles()
        Gets the List of Files from the clipboard which had previously been registered. This is equivalent to invoking getContent(DataFormat.FILES). If no such entry exists, null is returned.
        Returns:
        The List of Files on the clipboard associated with DataFormat.FILES, or null if there is not one.