java 雷达图,JFreeChart 生成雷达图（急）解决思路(2)

Java codepublic class MySpiderWebPlot extends SpiderWebPlot {

private int ticks = DEFAULT_TICKS;

private static final int DEFAULT_TICKS = 5;

private NumberFormat format = NumberFormat.getInstance();

private static final double PERPENDICULAR = 90;

private static final double TICK_SCALE = 0.015;

private int valueLabelGap = DEFAULT_GAP;

private static final int DEFAULT_GAP = 20;

private static final double THRESHOLD = 15;

MySpiderWebPlot(CategoryDataset createCategoryDataset) {

super(createCategoryDataset);

}

@Override

protected void drawLabel(final Graphics2D g2, final Rectangle2D plotArea,

final double value, final int cat, final double startAngle,

final double extent) {

super.drawLabel(g2, plotArea, value, cat, startAngle, extent);

final FontRenderContext frc = g2.getFontRenderContext();

final double[] transformed = new double[2];

final double[] transformer = new double[2];

final Arc2D arc1 = new Arc2D.Double(plotArea, startAngle, 0, Arc2D.OPEN);

for (int i = 1; i <= ticks; i++) {

final Point2D point1 = arc1.getEndPoint();

final double deltaX = plotArea.getCenterX();

final double deltaY = plotArea.getCenterY();

double labelX = point1.getX() - deltaX;

double labelY = point1.getY() - deltaY;

final double scale = ((double) i / (double) ticks);

final AffineTransform tx = AffineTransform.getScaleInstance(scale,

scale);

final AffineTransform pointTrans = AffineTransform

.getScaleInstance(scale + TICK_SCALE, scale + TICK_SCALE);

transformer[0] = labelX;

transformer[1] = labelY;

pointTrans.transform(transformer, 0, transformed, 0, 1);

final double pointX = transformed[0] + deltaX;

final double pointY = transformed[1] + deltaY;

tx.transform(transformer, 0, transformed, 0, 1);

labelX = transformed[0] + deltaX;

labelY = transformed[1] + deltaY;

double rotated = (PERPENDICULAR);

AffineTransform rotateTrans = AffineTransform.getRotateInstance(

Math.toRadians(rotated), labelX, labelY);

transformer[0] = pointX;

transformer[1] = pointY;

rotateTrans.transform(transformer, 0, transformed, 0, 1);

final double x1 = transformed[0];

final double y1 = transformed[1];

rotated = (-PERPENDICULAR);

rotateTrans = AffineTransform.getRotateInstance(

Math.toRadians(rotated), labelX, labelY);

rotateTrans.transform(transformer, 0, transformed, 0, 1);

final Composite saveComposite = g2.getComposite();

g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER,

1.0f));

g2.draw(new Line2D.Double(transformed[0], transformed[1], x1, y1));