ava JFreeChart createAreaChart生成折线图报表代码

折线图效果图:



import java.awt.Color;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.jfree.chart.ChartFactory;

import org.jfree.chart.ChartUtilities;

import org.jfree.chart.JFreeChart;

import org.jfree.chart.axis.CategoryAxis;

import org.jfree.chart.axis.CategoryLabelPositions;

import org.jfree.chart.plot.CategoryPlot;

import org.jfree.chart.plot.PlotOrientation;

import org.jfree.data.category.CategoryDataset;

import org.jfree.data.category.DefaultCategoryDataset;

import org.jfree.ui.RectangleInsets;

public class AreaChartServlet extends HttpServlet {

private static final long serialVersionUID = 5852523271721922574L;

public AreaChartServlet() {

super();

}

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

this.doPost(request, response);

}

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

// 设置返回类型为图片

response.setContentType("image/png");

// 获取数据集对象

CategoryDataset dataset = createDataset();

// 创建图形对象

JFreeChart jfreechart = ChartFactory.createAreaChart("08年图书销售量排名",

"按季度", "销量", dataset, PlotOrientation.VERTICAL, true, true,

false);

// 获得图表区域对象

CategoryPlot categoryplot = (CategoryPlot) jfreechart.getPlot();

//设置前景色为50%透明

categoryplot.setForegroundAlpha(0.5F);

//设置X轴偏移量

categoryplot.setAxisOffset(new RectangleInsets(5D, 5D, 5D, 5D));

//设置北景色为浅灰色

categoryplot.setBackgroundPaint(Color.lightGray);

//设置显示网格线

categoryplot.setDomainGridlinesVisible(true);

//设置网格线为白色

categoryplot.setDomainGridlinePaint(Color.white);

//设置显示边界线

categoryplot.setRangeGridlinesVisible(true);

//设置显示边界线为白色

categoryplot.setRangeGridlinePaint(Color.white);

//获得X轴对象

CategoryAxis categoryaxis = categoryplot.getDomainAxis();

//设置X轴标签位置为45度角

categoryaxis.setCategoryLabelPositions(CategoryLabelPositions.UP_45);

//设置与X轴的补白为0

categoryaxis.setLowerMargin(0.0D);

categoryaxis.setUpperMargin(0.0D);

// 将图表已数据流的方式返回给客户端

ChartUtilities.writeChartAsPNG(response.getOutputStream(), jfreechart,

500, 270);

}

/**

* 返回数据集

*

* @return

*/

private static CategoryDataset createDataset() {

// 时间维度

String[] category1 = { "第一季度", "第二季度", "第三季度", "第四季度" };

// 分类维度

String[] category2 = { "JAVA", "C/C++", "PHP" };

DefaultCategoryDataset defaultdataset = new DefaultCategoryDataset();

for (int i = 0; i < category1.length; i++) {

String category = category1[i];

for (int j = 0; j < category2.length; j++) {

String cat = category2[j];

// 模拟添加数据

defaultdataset.addValue(DataUtils.getRandomData(), cat, category);

}

}

return defaultdataset;

}

}