Image (JavaFX 17)

Module javafx.graphics
Package javafx.scene.image

## Class Image

- java.lang.Object
- - javafx.scene.image.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:

  - BMP
  - GIF
  - JPEG
  - PNG

  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.

  If a URL string is passed to a constructor, it be any of the following:

  1. the name of a resource that can be resolved by the context `ClassLoader` for this thread
  2. a file path that can be resolved by `File`
  3. a URL that can be resolved by `URL` and for which a protocol handler exists

  The RFC 2397 "data" scheme for URLs is supported in addition to the protocol handlers that are registered for the application. If a URL uses the "data" scheme, the data must be base64-encoded and the MIME type must either be empty or a subtype of the `image` type.

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

  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 Summary

    Properties
    Type | Property | Description
    --- | --- | ---
    `ReadOnlyBooleanProperty` | `error` | Indicates whether an error was detected while loading an image.
    `ReadOnlyObjectProperty<Exception>` | `exception` | The exception which caused image loading to fail.
    `ReadOnlyDoubleProperty` | `height` | The image height or `0` if the image loading fails.
    `ReadOnlyDoubleProperty` | `progress` | The approximate percentage of image's loading that has been completed.
    `ReadOnlyDoubleProperty` | `width` | The image width or `0` if the image loading fails.

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `Image​(InputStream is)` | Constructs an `Image` with content loaded from the specified input stream.
    `Image​(InputStream is, double requestedWidth, double requestedHeight, boolean preserveRatio, boolean smooth)` | Constructs a new `Image` with the specified parameters.
    `Image​(String url)` | Constructs an `Image` with content loaded from the specified URL.
    `Image​(String url, boolean backgroundLoading)` | Constructs an `Image` with content loaded from the specified URL using the specified parameters.
    `Image​(String url, double requestedWidth, double requestedHeight, boolean preserveRatio, boolean smooth)` | Constructs an `Image` with content loaded from the specified URL using the specified parameters.
    `Image​(String url, double requestedWidth, double requestedHeight, boolean preserveRatio, boolean smooth, boolean backgroundLoading)` | Constructs an `Image` with content loaded from the specified URL using the specified parameters.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `cancel()` | Cancels the background loading of this image.
    `ReadOnlyBooleanProperty` | `errorProperty()` | Indicates whether an error was detected while loading an image.
    `ReadOnlyObjectProperty<Exception>` | `exceptionProperty()` | The exception which caused image loading to fail.
    `Exception` | `getException()` | Gets the value of the property exception.
    `double` | `getHeight()` | Gets the value of the property height.
    `PixelReader` | `getPixelReader()` | This method returns a `PixelReader` that provides access to read the pixels of the image, if the image is readable.
    `double` | `getProgress()` | Gets the value of the property progress.
    `double` | `getRequestedHeight()` | Gets the height of the bounding box within which the source image is resized as necessary to fit.
    `double` | `getRequestedWidth()` | Gets the width of the bounding box within which the source image is resized as necessary to fit.
    `String` | `getUrl()` | Returns the url used to fetch the pixel data contained in the Image instance, if specified in the constructor.
    `double` | `getWidth()` | Gets the value of the property width.
    `ReadOnlyDoubleProperty` | `heightProperty()` | The image height or `0` if the image loading fails.
    `boolean` | `isBackgroundLoading()` | Indicates whether the image is being loaded in the background.
    `boolean` | `isError()` | Gets the value of the property error.
    `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`.
    `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`.
    `ReadOnlyDoubleProperty` | `progressProperty()` | The approximate percentage of image's loading that has been completed.
    `ReadOnlyDoubleProperty` | `widthProperty()` | The image width or `0` if the image loading fails.

    - ### Methods declared in class java.lang.Object

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

- - ### 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` - a resource path, file path, or URL
      Throws:
        `NullPointerException` - if `url` is null
        `IllegalArgumentException` - if `url` is invalid or unsupported

    - #### Image

          public Image​(String url,
                       boolean backgroundLoading)

      Constructs an `Image` with content loaded from the specified URL using the specified parameters.
      Parameters:
        `url` - a resource path, file path, or URL
        `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)

      Constructs an `Image` with content loaded from the specified URL using the specified parameters.
      Parameters:
        `url` - a resource path, file path, or URL
        `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)

      Constructs an `Image` with content loaded from the specified URL using the specified parameters.
      Parameters:
        `url` - a resource path, file path, or URL
        `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)

      Constructs 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)

      Constructs 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