Question

我有条形图的例子，我希望以简单易读的格式显示数据：

import java.text.DecimalFormat;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.animation.AnimationTimer;
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.chart.AreaChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart.Data;
import javafx.scene.chart.XYChart.Series;
import javafx.scene.control.Tooltip;
import javafx.stage.Stage;

public class MainApp extends Application
{
    private static final int MAX_DATA_POINTS = 50;

    private Series series;
    private Series series2;
    private int xSeriesData = 0;
    private ConcurrentLinkedQueue<Number> dataQ = new ConcurrentLinkedQueue<Number>();
    private ConcurrentLinkedQueue<Number> dataQ2 = new ConcurrentLinkedQueue<Number>();
    private ExecutorService executor;
    private AddToQueue addToQueue;
    private NumberAxis xAxis;

    private void init(Stage primaryStage)
    {
        xAxis = new NumberAxis(0, MAX_DATA_POINTS, MAX_DATA_POINTS / 10);
        xAxis.setForceZeroInRange(false);
        xAxis.setAutoRanging(false);

        NumberAxis yAxis = new NumberAxis();
        yAxis.setAutoRanging(true);

        //-- Chart
        final AreaChart<Number, Number> sc = new AreaChart<Number, Number>(xAxis, yAxis);

        sc.setAnimated(false);
        sc.setCreateSymbols(false);
        sc.setId("liveAreaChart");
        sc.setTitle("Animated Area Chart");

        //-- Chart Series
        series = new AreaChart.Series<Number, Number>();
        series.setName("Area Chart Series");
        series2 = new AreaChart.Series<Number, Number>();
        series2.setName("Area Chart Series");
        sc.getData().addAll(series, series2);

        xAxis.setTickLabelsVisible(false);
        xAxis.setTickMarkVisible(false);
        xAxis.setMinorTickVisible(false);

        primaryStage.setScene(new Scene(sc));
    }

    @Override
    public void start(Stage primaryStage) throws Exception
    {
        init(primaryStage);
        primaryStage.show();

        //-- Prepare Executor Services
        executor = Executors.newCachedThreadPool(new ThreadFactory()
        {
            @Override
            public Thread newThread(Runnable r)
            {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                return thread;
            }
        });
        addToQueue = new AddToQueue();
        executor.execute(addToQueue);
        //-- Prepare Timeline
        prepareTimeline();
    }

    public static void main(String[] args)
    {
        launch(args);
    }

    private class AddToQueue implements Runnable
    {
        @Override
        public void run()
        {
            try
            {
                // add a item of random data to queue
                dataQ.add(randomInteger());
                dataQ2.add(randomInteger());
                Thread.sleep(400);
                executor.execute(this);
            }
            catch (InterruptedException ex)
            {
                Logger.getLogger(MainApp.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }

    public int randomInteger()
    {
        int min = 100;
        int max = 900000000;

        int randomNum = min + (int) (Math.random() * ((max - min) + 1));
        return randomNum;
    }

    private static String readableFileSize(long size)
    {
        if (size <= 0)
            return "0";
        final String[] units = new String[]
        {
            "B", "kB", "MB", "GB", "TB"
        };
        int digitGroups = (int) (Math.log10(size) / Math.log10(1024));
        return new DecimalFormat("#,##0.#").format(size / Math.pow(1024, digitGroups)) + " " + units[digitGroups];
    }

    //-- Timeline gets called in the JavaFX Main thread
    private void prepareTimeline()
    {
        // Every frame to take any data from queue and add to chart
        new AnimationTimer()
        {
            @Override
            public void handle(long now)
            {
                addDataToSeries();
            }
        }.start();
    }

    private void addDataToSeries()
    {
        for (int i = 0; i < 20; i++)
        { //-- add 20 numbers to the plot+
            if (dataQ.isEmpty())
                break;
//            series.getData().add(new AreaChart.Data(xSeriesData++, dataQ.remove()));


            Data data = new AreaChart.Data(xSeriesData++, dataQ.remove());

            series.getData().add(data);

            data.nodeProperty().addListener(new ChangeListener<Node>()
            {
                @Override
                public void changed(ObservableValue<? extends Node> arg0, Node arg1,
                    Node arg2)
                {
                    Tooltip t = new Tooltip(data.getYValue().toString() + '\n' + data.getXValue());
                    Tooltip.install(arg2, t);
                    data.nodeProperty().removeListener(this);
                }
            });



            if (dataQ2.isEmpty())
                break;
            series2.getData().add(new AreaChart.Data(xSeriesData, dataQ2.remove()));
        }
        // remove points to keep us at no more than MAX_DATA_POINTS
        if (series.getData().size() > MAX_DATA_POINTS)
        {
            series.getData().remove(0, series.getData().size() - MAX_DATA_POINTS);
        }

        // remove points to keep us at no more than MAX_DATA_POINTS
        if (series2.getData().size() > MAX_DATA_POINTS)
        {
            series2.getData().remove(0, series2.getData().size() - MAX_DATA_POINTS);
        }

        // update
        xAxis.setLowerBound(xSeriesData - MAX_DATA_POINTS);
        xAxis.setUpperBound(xSeriesData - 1);
    }
}

原始值以字节为单位。基于我希望在将值插入图表之前使用方法readableFileSize(long size)转换以字节/ GB /兆字节等为单位的值。问题是这个方法返回String。

如何重构代码以使用此方法？

PS。根据提案，我尝试了这个：

import java.text.DecimalFormat;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.animation.AnimationTimer;
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.chart.AreaChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart.Data;
import javafx.scene.chart.XYChart.Series;
import javafx.scene.control.Tooltip;
import javafx.stage.Stage;

public class MainApp extends Application
{
    private static final int MAX_DATA_POINTS = 50;

    private Series series;
    private Series series2;
    private int xSeriesData = 0;
    private ConcurrentLinkedQueue<Number> dataQ = new ConcurrentLinkedQueue<Number>();
    private ConcurrentLinkedQueue<Number> dataQ2 = new ConcurrentLinkedQueue<Number>();
    private ExecutorService executor;
    private AddToQueue addToQueue;
    private NumberAxis xAxis;
    private NumberAxis yAxis;

    private void init(Stage primaryStage)
    {
        xAxis = new NumberAxis(0, MAX_DATA_POINTS, MAX_DATA_POINTS / 10);
        xAxis.setForceZeroInRange(false);
        xAxis.setAutoRanging(false);

        yAxis = new NumberAxis();
        yAxis.setAutoRanging(true);

        //-- Chart
        final AreaChart<Number, Number> sc = new AreaChart<Number, Number>(xAxis, yAxis);

        sc.setAnimated(false);
        sc.setCreateSymbols(false);
        sc.setId("liveAreaChart");
        sc.setTitle("Animated Area Chart");

        //-- Chart Series
        series = new AreaChart.Series<Number, Number>();
        series.setName("Area Chart Series");
        series2 = new AreaChart.Series<Number, Number>();
        series2.setName("Area Chart Series");
        sc.getData().addAll(series, series2);

        xAxis.setTickLabelsVisible(false);
        xAxis.setTickMarkVisible(false);
        xAxis.setMinorTickVisible(false);

        primaryStage.setScene(new Scene(sc));
    }

    @Override
    public void start(Stage primaryStage) throws Exception
    {
        init(primaryStage);
        primaryStage.show();

        //-- Prepare Executor Services
        executor = Executors.newCachedThreadPool(new ThreadFactory()
        {
            @Override
            public Thread newThread(Runnable r)
            {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                return thread;
            }
        });
        addToQueue = new AddToQueue();
        executor.execute(addToQueue);
        //-- Prepare Timeline
        prepareTimeline();
    }

    public static void main(String[] args)
    {
        launch(args);
    }

    private class AddToQueue implements Runnable
    {



        @Override
        public void run()
        {
            try
            {
                int size = randomInteger();

                final String[] units = new String[]
                {
                    "B", "kB", "MB", "GB", "TB"
                };
                int digitGroups = (int) (Math.log10(size) / Math.log10(1024));
                Long valueOf = Long.valueOf(new DecimalFormat("#,##0.#").format(size / Math.pow(1024, digitGroups)));

                yAxis.setTickLabelFormatter(new NumberAxis.DefaultFormatter(yAxis)
                {
                    @Override
                    public String toString(Number object)
                    {
                        return String.format("%6.4f " + units[digitGroups], object);
                    }
                });

                // add a item of random data to queue
                dataQ.add(valueOf);
                dataQ2.add(randomInteger());
                Thread.sleep(400);
                executor.execute(this);
            }
            catch (InterruptedException ex)
            {
                Logger.getLogger(MainApp.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }

    public int randomInteger()
    {
        int min = 100;
        int max = 900000000;

        int randomNum = min + (int) (Math.random() * ((max - min) + 1));
        return randomNum;
    }

    private static String readableFileSize(long size)
    {
        if (size <= 0)
            return "0";
        final String[] units = new String[]
        {
            "B", "kB", "MB", "GB", "TB"
        };
        int digitGroups = (int) (Math.log10(size) / Math.log10(1024));
        return new DecimalFormat("#,##0.#").format(size / Math.pow(1024, digitGroups)) + " " + units[digitGroups];
    }

    //-- Timeline gets called in the JavaFX Main thread
    private void prepareTimeline()
    {
        // Every frame to take any data from queue and add to chart
        new AnimationTimer()
        {
            @Override
            public void handle(long now)
            {
                addDataToSeries();
            }
        }.start();
    }

    private void addDataToSeries()
    {
        for (int i = 0; i < 20; i++)
        { //-- add 20 numbers to the plot+
            if (dataQ.isEmpty())
                break;
//            series.getData().add(new AreaChart.Data(xSeriesData++, dataQ.remove()));


            Data data = new AreaChart.Data(xSeriesData++, dataQ.remove());

            series.getData().add(data);

            data.nodeProperty().addListener(new ChangeListener<Node>()
            {
                @Override
                public void changed(ObservableValue<? extends Node> arg0, Node arg1,
                    Node arg2)
                {
                    Tooltip t = new Tooltip(data.getYValue().toString() + '\n' + data.getXValue());
                    Tooltip.install(arg2, t);
                    data.nodeProperty().removeListener(this);
                }
            });



            if (dataQ2.isEmpty())
                break;
            series2.getData().add(new AreaChart.Data(xSeriesData, dataQ2.remove()));
        }
        // remove points to keep us at no more than MAX_DATA_POINTS
        if (series.getData().size() > MAX_DATA_POINTS)
        {
            series.getData().remove(0, series.getData().size() - MAX_DATA_POINTS);
        }

        // remove points to keep us at no more than MAX_DATA_POINTS
        if (series2.getData().size() > MAX_DATA_POINTS)
        {
            series2.getData().remove(0, series2.getData().size() - MAX_DATA_POINTS);
        }

        // update
        xAxis.setLowerBound(xSeriesData - MAX_DATA_POINTS);
        xAxis.setUpperBound(xSeriesData - 1);
    }
}

Answer 1

您可以使用setTickLabelFormatter作为轴刻度标签。

一个简单的例子：

import java.text.DecimalFormat;

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.stage.Stage;
import javafx.util.StringConverter;

public class LineChartSample extends Application {

    @Override
    public void start(Stage stage) {

        final NumberAxis xAxis = new NumberAxis();
        final NumberAxis yAxis = new NumberAxis();
        final LineChart<Number, Number> lineChart = new LineChart<Number, Number>(xAxis, yAxis);

        XYChart.Series<Number,Number> series = new XYChart.Series<Number,Number>();

        for (int i = 0; i < 10000000; i += 1000) {
            series.getData().add(new XYChart.Data(i, i));
        }

        yAxis.setTickLabelFormatter(new StringConverter<Number>() {

            @Override
            public String toString(Number object) {

                // conversion code from:
                // http://stackoverflow.com/questions/13539871/converting-kb-to-mb-gb-tb-dynamicaly
                double size = object.doubleValue();

                String hrSize = null;

                double b = size;
                double k = size / 1024.0;
                double m = ((size / 1024.0) / 1024.0);
                double g = (((size / 1024.0) / 1024.0) / 1024.0);
                double t = ((((size / 1024.0) / 1024.0) / 1024.0) / 1024.0);

                DecimalFormat dec = new DecimalFormat("0.00");

                if (t > 1) {
                    hrSize = dec.format(t).concat(" TB");
                } else if (g > 1) {
                    hrSize = dec.format(g).concat(" GB");
                } else if (m > 1) {
                    hrSize = dec.format(m).concat(" MB");
                } else if (k > 1) {
                    hrSize = dec.format(k).concat(" KB");
                } else {
                    hrSize = dec.format(b).concat(" Bytes");
                }

                return hrSize;
            }

            @Override
            public Number fromString(String string) {

                // TODO: convert from text to number
                return null;
            }

        });

        Scene scene = new Scene(lineChart, 800, 600);
        lineChart.getData().add(series);

        stage.setScene(scene);
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

以易读的格式转换图表值

1 个答案: