chartutilities.java

关于jfreechart的电子说明书,一种说明图型使用的介绍

     * @param chart  the chart (<code>null</code> not permitted).
     * @param width  the image width.
     * @param height  the image height.
     * @param info  the chart rendering info (<code>null</code> permitted).
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void saveChartAsJPEG(File file,
                                       JFreeChart chart,
                                       int width,
                                       int height,
                                       ChartRenderingInfo info) 
        throws IOException {

        if (file == null) {
            throw new IllegalArgumentException("Null 'file' argument.");
        }
        if (chart == null) {
            throw new IllegalArgumentException("Null 'chart' argument.");
        }
        OutputStream out = new BufferedOutputStream(new FileOutputStream(file));
        writeChartAsJPEG(out, chart, width, height, info);
        out.close();

    }

    /**
     * Saves a chart to a file in JPEG format.  This method allows you to pass 
     * in a {@link ChartRenderingInfo} object, to collect information about the 
     * chart dimensions/entities.  You will need this info if you want to 
     * create an HTML image map.
     *
     * @param file  the file name (<code>null</code> not permitted).
     * @param quality  the quality setting.
     * @param chart  the chart (<code>null</code> not permitted).
     * @param width  the image width.
     * @param height  the image height.
     * @param info  the chart rendering info (<code>null</code> permitted).
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void saveChartAsJPEG(File file,
                                       float quality,
                                       JFreeChart chart,
                                       int width,
                                       int height,
                                       ChartRenderingInfo info) 
        throws IOException {

        if (file == null) {
            throw new IllegalArgumentException("Null 'file' argument.");
        }
        if (chart == null) {
            throw new IllegalArgumentException("Null 'chart' argument.");
        }
        OutputStream out = new BufferedOutputStream(new FileOutputStream(file));
        writeChartAsJPEG(out, quality, chart, width, height, info);
        out.close();

    }

    /**
     * Writes a {@link BufferedImage} to an output stream in JPEG format.
     *
     * @param out  the output stream (<code>null</code> not permitted).
     * @param image  the image (<code>null</code> not permitted).
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void writeBufferedImageAsJPEG(OutputStream out, 
                                                BufferedImage image)
        throws IOException {

        // defer argument checking...
        writeBufferedImageAsJPEG(out, 0.75f, image);

    }

    /**
     * Writes a {@link BufferedImage} to an output stream in JPEG format.
     *
     * @param out  the output stream (<code>null</code> not permitted).
     * @param quality  the image quality (0.0f to 1.0f).
     * @param image  the image (<code>null</code> not permitted).
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void writeBufferedImageAsJPEG(OutputStream out, float quality,
                                                BufferedImage image) 
        throws IOException {

        EncoderUtil.writeBufferedImage(image, ImageFormat.JPEG, out, quality);

    }

    /**
     * Writes a {@link BufferedImage} to an output stream in PNG format.
     *
     * @param out  the output stream (<code>null</code> not permitted).
     * @param image  the image (<code>null</code> not permitted).
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void writeBufferedImageAsPNG(OutputStream out, 
                                               BufferedImage image)
        throws IOException {

        EncoderUtil.writeBufferedImage(image, ImageFormat.PNG, out);

    }

    /**
     * Writes a {@link BufferedImage} to an output stream in PNG format.
     *
     * @param out  the output stream (<code>null</code> not permitted).
     * @param image  the image (<code>null</code> not permitted).
     * @param encodeAlpha  encode alpha?
     * @param compression  the compression level (0-9).
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void writeBufferedImageAsPNG(OutputStream out,
                                               BufferedImage image,
                                               boolean encodeAlpha,
                                               int compression) 
        throws IOException {

        EncoderUtil.writeBufferedImage(
            image, ImageFormat.PNG, out, compression, encodeAlpha
        );
    }

    /**
     * Encodes a {@link BufferedImage} to PNG format.
     *
     * @param image  the image (<code>null</code> not permitted).
     *
     * @return A byte array in PNG format.
     * 
     * @throws IOException if there is an I/O problem.
     */
    public static byte[] encodeAsPNG(BufferedImage image) throws IOException {
        return EncoderUtil.encode(image, ImageFormat.PNG);
    }

    /**
     * Encodes a {@link BufferedImage} to PNG format.
     *
     * @param image  the image (<code>null</code> not permitted).
     * @param encodeAlpha  encode alpha?
     * @param compression  the PNG compression level (0-9).
     *
     * @return The byte array in PNG format.
     * 
     * @throws IOException if there is an I/O problem.
     */
    public static byte[] encodeAsPNG(BufferedImage image, boolean encodeAlpha, 
                                     int compression) 
        throws IOException {
        return EncoderUtil.encode(
            image, ImageFormat.PNG, compression, encodeAlpha
        );
    }

    /**
     * Writes an image map to an output stream.
     *
     * @param writer  the writer (<code>null</code> not permitted).
     * @param name  the map name (<code>null</code> not permitted).
     * @param info  the chart rendering info (<code>null</code> not permitted).
     * @param useOverLibForToolTips  whether to use OverLIB for tooltips
     *                               (http://www.bosrup.com/web/overlib/).
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void writeImageMap(PrintWriter writer,
                                     String name,
                                     ChartRenderingInfo info,
                                     boolean useOverLibForToolTips) 
        throws IOException {

        ToolTipTagFragmentGenerator toolTipTagFragmentGenerator = null;
        if (useOverLibForToolTips) {
            toolTipTagFragmentGenerator 
                = new OverLIBToolTipTagFragmentGenerator();
        }
        else {
            toolTipTagFragmentGenerator 
                = new StandardToolTipTagFragmentGenerator();
        }
        ImageMapUtilities.writeImageMap(
            writer, name, info, toolTipTagFragmentGenerator, 
            new StandardURLTagFragmentGenerator()
        );

    }

    /**
     * Writes an image map to an output stream.
     *
     * @param writer  the writer (<code>null</code> not permitted).
     * @param name  the map name (<code>null</code> not permitted).
     * @param info  the chart rendering info (<code>null</code> not permitted).
     * @param toolTipTagFragmentGenerator  the tool tip generator.
     * @param urlTagFragmentGenerator  the url generator.
     *
     * @throws IOException if there are any I/O errors.
     */
    public static void writeImageMap(PrintWriter writer, String name, 
            ChartRenderingInfo info, 
            ToolTipTagFragmentGenerator toolTipTagFragmentGenerator,
            URLTagFragmentGenerator urlTagFragmentGenerator)
            throws IOException {

        writer.println(
            ImageMapUtilities.getImageMap(
                name, info, toolTipTagFragmentGenerator, urlTagFragmentGenerator
            )
        );
    }

    /**
     * Creates an HTML image map.
     *
     * @param name  the map name (<code>null</code> not permitted).
     * @param info  the chart rendering info (<code>null</code> not permitted).
     *
     * @return The map tag.
     */
    public static String getImageMap(String name, ChartRenderingInfo info) {
        return ImageMapUtilities.getImageMap(
            name,
            info,
            new StandardToolTipTagFragmentGenerator(),
            new StandardURLTagFragmentGenerator()
        );
    }

    /**
     * Creates an HTML image map.
     *
     * @param name  the map name (<code>null</code> not permitted).
     * @param info  the chart rendering info (<code>null</code> not permitted).
     * @param toolTipTagFragmentGenerator  the tool tip generator.
     * @param urlTagFragmentGenerator  the url generator.
     *
     * @return The map tag.
     */
    public static String getImageMap(String name,
                     ChartRenderingInfo info,
                     ToolTipTagFragmentGenerator toolTipTagFragmentGenerator,
                     URLTagFragmentGenerator urlTagFragmentGenerator) {

        return ImageMapUtilities.getImageMap(
            name, info, toolTipTagFragmentGenerator, urlTagFragmentGenerator
        );
        
    }

}