package com.lei.jfreechart;import javax.swing.JPanel;import org.jfree.chart.ChartFactory;import org.jfree.chart.ChartPanel;import org.jfree.chart.JFreeChart;import org.jfree.chart.axis.NumberAxis;import org.jfree.chart.plot.CategoryPlot;import org.jfree.chart.plot.PlotOrientation;import org.jfree.data.category.DefaultCategoryDataset;import org.jfree.ui.ApplicationFrame;import org.jfree.ui.RefineryUtilities;public class LineCharts extends ApplicationFrame {/****/private static final long serialVersionUID = 1L;public LineCharts(String s) {  super(s);  setContentPane(createDemoLine());}public static void main(String[] args) {  LineCharts fjc = new LineCharts("折線圖");  fjc.pack();  RefineryUtilities.centerFrameOnScreen(fjc);  fjc.setVisible(true);}// 生成顯示圖表的面板public static JPanel createDemoLine() {  JFreeChart jfreechart = createChart(createDataset());  return new ChartPanel(jfreechart);}// 生成圖表主對象JFreeChartpublic static JFreeChart createChart(DefaultCategoryDataset linedataset) {  // 定義圖表對象  JFreeChart chart = ChartFactory.createLineChart("一季度銷售曲線", //折線圖名稱   "時間", // 橫坐標名稱   "銷售額(百萬)", // 縱坐標名稱   linedataset, // 數據   PlotOrientation.VERTICAL, // 水平顯示圖像   true, // include legend   true, // tooltips   false // urls   );  CategoryPlot plot = chart.getCategoryPlot();  plot.setRangeGridlinesVisible(true); //是否顯示格子線  plot.setBackgroundAlpha(0.3f); //設置背景透明度  NumberAxis rangeAxis = (NumberAxis)plot.getRangeAxis();  rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());  rangeAxis.setAutoRangeIncludesZero(true);  rangeAxis.setUpperMargin(0.20);  rangeAxis.setLabelAngle(Math.PI / 2.0);  return chart;}// 生成數據public static DefaultCategoryDataset createDataset() {  DefaultCategoryDataset linedataset = new DefaultCategoryDataset();  // 各曲線名稱  String series1 = "冰箱";  String series2 = "彩電";  String series3 = "洗衣機";  // 橫軸名稱(列名稱)  String type1 = "1月";  String type2 = "2月";  String type3 = "3月";  linedataset.addValue(0.0, series1, type1);  linedataset.addValue(4.2, series1, type2);  linedataset.addValue(3.9, series1, type3);  linedataset.addValue(1.0, series2, type1);  linedataset.addValue(5.2, series2, type2);  linedataset.addValue(7.9, series2, type3);  linedataset.addValue(2.0, series3, type1);  linedataset.addValue(9.2, series3, type2);  linedataset.addValue(8.9, series3, type3);  return linedataset;}}