Class Image

  • Direct Known Subclasses:
    WritableImage


    public class Image
    extends Object
    The Image class represents graphical images and is used for loading images from a specified URL.

    Supported image formats are:

    Images can be resized as they are loaded (for example to reduce the amount of memory consumed by the image). The application can specify the quality of filtering used when scaling, and whether or not to preserve the original image's aspect ratio.

    All URLs supported by URL can be passed to the constructor. If the passed string is not a valid URL, but a path instead, the Image is searched on the classpath in that case.

    Use ImageView for displaying images loaded with this class. The same Image instance can be displayed by multiple ImageViews.

    Example code for loading images.

    import javafx.scene.image.Image;
    
    // load an image in background, displaying a placeholder while it's loading
    // (assuming there's an ImageView node somewhere displaying this image)
    // The image is located in default package of the classpath
    Image image1 = new Image("/flower.png", true);
    
    // load an image and resize it to 100x150 without preserving its original
    // aspect ratio
    // The image is located in my.res package of the classpath
    Image image2 = new Image("my/res/flower.png", 100, 150, false, false);
    
    // load an image and resize it to width of 100 while preserving its
    // original aspect ratio, using faster filtering method
    // The image is downloaded from the supplied URL through http protocol
    Image image3 = new Image("http://sample.com/res/flower.png", 100, 0, false, false);
    
    // load an image and resize it only in one dimension, to the height of 100 and
    // the original width, without preserving original aspect ratio
    // The image is located in the current working directory
    Image image4 = new Image("file:flower.png", 0, 100, false, false);
    
    
    Since:
    JavaFX 2.0
    • Property Detail

      • progress

        public final ReadOnlyDoubleProperty progressProperty
        The approximate percentage of image's loading that has been completed. A positive value between 0 and 1 where 0 is 0% and 1 is 100%.
        Default value:
        0
        See Also:
        getProgress()
      • width

        public final ReadOnlyDoubleProperty widthProperty
        The image width or 0 if the image loading fails. While the image is being loaded it is set to 0.
        See Also:
        getWidth()
      • height

        public final ReadOnlyDoubleProperty heightProperty
        The image height or 0 if the image loading fails. While the image is being loaded it is set to 0.
        See Also:
        getHeight()
      • error

        public final ReadOnlyBooleanProperty errorProperty
        Indicates whether an error was detected while loading an image.
        Default value:
        false
        See Also:
        isError()
      • exception

        public final ReadOnlyObjectProperty<Exception> exceptionProperty
        The exception which caused image loading to fail. Contains a non-null value only if the error property is set to true.
        Since:
        JavaFX 8.0
        See Also:
        getException()
    • Constructor Detail

      • Image

        public Image​(String url)
        Constructs an Image with content loaded from the specified url.
        Parameters:
        url - the string representing the URL to use in fetching the pixel data
        Throws:
        NullPointerException - if URL is null
        IllegalArgumentException - if URL is invalid or unsupported
      • Image

        public Image​(String url,
                     boolean backgroundLoading)
        Construct a new Image with the specified parameters.
        Parameters:
        url - the string representing the URL to use in fetching the pixel data
        backgroundLoading - indicates whether the image is being loaded in the background
        Throws:
        NullPointerException - if URL is null
        IllegalArgumentException - if URL is invalid or unsupported
      • Image

        public Image​(String url,
                     double requestedWidth,
                     double requestedHeight,
                     boolean preserveRatio,
                     boolean smooth)
        Construct a new Image with the specified parameters.
        Parameters:
        url - the string representing the URL to use in fetching the pixel data
        requestedWidth - the image's bounding box width
        requestedHeight - the image's bounding box height
        preserveRatio - indicates whether to preserve the aspect ratio of the original image when scaling to fit the image within the specified bounding box
        smooth - indicates whether to use a better quality filtering algorithm or a faster one when scaling this image to fit within the specified bounding box
        Throws:
        NullPointerException - if URL is null
        IllegalArgumentException - if URL is invalid or unsupported
      • Image

        public Image​(String url,
                     double requestedWidth,
                     double requestedHeight,
                     boolean preserveRatio,
                     boolean smooth,
                     boolean backgroundLoading)
        Construct a new Image with the specified parameters. The url without scheme is threated as relative to classpath, url with scheme is treated accordingly to the scheme using URL.openStream()
        Parameters:
        url - the string representing the URL to use in fetching the pixel data
        requestedWidth - the image's bounding box width
        requestedHeight - the image's bounding box height
        preserveRatio - indicates whether to preserve the aspect ratio of the original image when scaling to fit the image within the specified bounding box
        smooth - indicates whether to use a better quality filtering algorithm or a faster one when scaling this image to fit within the specified bounding box
        backgroundLoading - indicates whether the image is being loaded in the background
        Throws:
        NullPointerException - if URL is null
        IllegalArgumentException - if URL is invalid or unsupported
      • Image

        public Image​(InputStream is)
        Construct an Image with content loaded from the specified input stream.
        Parameters:
        is - the stream from which to load the image
        Throws:
        NullPointerException - if input stream is null
      • Image

        public Image​(InputStream is,
                     double requestedWidth,
                     double requestedHeight,
                     boolean preserveRatio,
                     boolean smooth)
        Construct a new Image with the specified parameters.
        Parameters:
        is - the stream from which to load the image
        requestedWidth - the image's bounding box width
        requestedHeight - the image's bounding box height
        preserveRatio - indicates whether to preserve the aspect ratio of the original image when scaling to fit the image within the specified bounding box
        smooth - indicates whether to use a better quality filtering algorithm or a faster one when scaling this image to fit within the specified bounding box
        Throws:
        NullPointerException - if input stream is null
    • Method Detail

      • getUrl

        public final String getUrl​()
        Returns the url used to fetch the pixel data contained in the Image instance, if specified in the constructor. If no url is provided in the constructor (for instance, if the Image is constructed from an InputStream), this method will return null.
        Returns:
        a String containing the URL used to fetch the pixel data for this Image instance.
        Since:
        9
      • getProgress

        public final double getProgress​()
        Gets the value of the property progress.
        Property description:
        The approximate percentage of image's loading that has been completed. A positive value between 0 and 1 where 0 is 0% and 1 is 100%.
        Default value:
        0
      • progressProperty

        public final ReadOnlyDoubleProperty progressProperty​()
        The approximate percentage of image's loading that has been completed. A positive value between 0 and 1 where 0 is 0% and 1 is 100%.
        Default value:
        0
        See Also:
        getProgress()
      • getRequestedWidth

        public final double getRequestedWidth​()
        Gets the width of the bounding box within which the source image is resized as necessary to fit. If set to a value <= 0, then the intrinsic width of the image will be used.

        See preserveRatio for information on interaction between image's requestedWidth, requestedHeight and preserveRatio attributes.

        Returns:
        The requested width
      • getRequestedHeight

        public final double getRequestedHeight​()
        Gets the height of the bounding box within which the source image is resized as necessary to fit. If set to a value <= 0, then the intrinsic height of the image will be used.

        See preserveRatio for information on interaction between image's requestedWidth, requestedHeight and preserveRatio attributes.

        Returns:
        The requested height
      • getWidth

        public final double getWidth​()
        Gets the value of the property width.
        Property description:
        The image width or 0 if the image loading fails. While the image is being loaded it is set to 0.
      • widthProperty

        public final ReadOnlyDoubleProperty widthProperty​()
        The image width or 0 if the image loading fails. While the image is being loaded it is set to 0.
        See Also:
        getWidth()
      • getHeight

        public final double getHeight​()
        Gets the value of the property height.
        Property description:
        The image height or 0 if the image loading fails. While the image is being loaded it is set to 0.
      • heightProperty

        public final ReadOnlyDoubleProperty heightProperty​()
        The image height or 0 if the image loading fails. While the image is being loaded it is set to 0.
        See Also:
        getHeight()
      • isPreserveRatio

        public final boolean isPreserveRatio​()
        Indicates whether to preserve the aspect ratio of the original image when scaling to fit the image within the bounding box provided by width and height.

        If set to true, it affects the dimensions of this Image in the following way:

        • If only width is set, height is scaled to preserve ratio
        • If only height is set, width is scaled to preserve ratio
        • If both are set, they both may be scaled to get the best fit in a width by height rectangle while preserving the original aspect ratio
        The reported width and height may be different from the initially set values if they needed to be adjusted to preserve aspect ratio. If unset or set to false, it affects the dimensions of this ImageView in the following way:
        • If only width is set, the image's width is scaled to match and height is unchanged;
        • If only height is set, the image's height is scaled to match and height is unchanged;
        • If both are set, the image is scaled to match both.
        Returns:
        true if the aspect ratio of the original image is to be preserved when scaling to fit the image within the bounding box provided by width and height.
      • isSmooth

        public final boolean isSmooth​()
        Indicates whether to use a better quality filtering algorithm or a faster one when scaling this image to fit within the bounding box provided by width and height.

        If not initialized or set to true a better quality filtering will be used, otherwise a faster but lesser quality filtering will be used.

        Returns:
        true if a better quality (but slower) filtering algorithm is used for scaling to fit within the bounding box provided by width and height.
      • isBackgroundLoading

        public final boolean isBackgroundLoading​()
        Indicates whether the image is being loaded in the background.
        Returns:
        true if the image is loaded in the background
      • isError

        public final boolean isError​()
        Gets the value of the property error.
        Property description:
        Indicates whether an error was detected while loading an image.
        Default value:
        false
      • errorProperty

        public final ReadOnlyBooleanProperty errorProperty​()
        Indicates whether an error was detected while loading an image.
        Default value:
        false
        See Also:
        isError()
      • getException

        public final Exception getException​()
        Gets the value of the property exception.
        Property description:
        The exception which caused image loading to fail. Contains a non-null value only if the error property is set to true.
        Since:
        JavaFX 8.0
      • exceptionProperty

        public final ReadOnlyObjectProperty<Exception> exceptionProperty​()
        The exception which caused image loading to fail. Contains a non-null value only if the error property is set to true.
        Since:
        JavaFX 8.0
        See Also:
        getException()
      • cancel

        public void cancel​()
        Cancels the background loading of this image.

        Has no effect if this image isn't loaded in background or if loading has already completed.

      • getPixelReader

        public final PixelReader getPixelReader​()
        This method returns a PixelReader that provides access to read the pixels of the image, if the image is readable. If this method returns null then this image does not support reading at this time. This method will return null if the image is being loaded from a source and is still incomplete {the progress is still <1.0) or if there was an error. This method may also return null for some images in a format that is not supported for reading and writing pixels to.
        Returns:
        the PixelReader for reading the pixel data of the image
        Since:
        JavaFX 2.2