struts开发实践-柱形图、饼状图实例
本案主要功能是完成柱形图、饼状图的绘制，并将柱形图、饼状图生成jpg图形并显示。
1。调用的主要函数说明:请参考曲线图部分的说明
2。曲线图绘制文件
/***********program StatRectFrame begin*********************/
package test;
import java.awt.*;
import java.awt.geom.*;
import java.awt.image.*;
import javax.swing.JFrame;
import java.lang.Math;
/**
* 绘图：柱形图；饼形图
*/
public class StatRectFrame
extends JFrame {
private int[] result;
private String[] title;
private int statStyle;
private Color[] color = {
Color.blue, new Color(255, 92, 0), new Color(255, 0, 30),
new Color(0, 255, 30), new Color(255, 0, 240), Color.cyan};
/**入口参数：结果集，标题集，统计类型：柱状图 or 饼状图 */
public StatRectFrame(int[] result, String[] title, int statStyle) {
this.result = result;
this.title = title;
this.statStyle = statStyle;
}
public void paint(Graphics g) {
Graphics2D g2 = (Graphics2D) g;
Dimension dim = this.getSize();
if (statStyle == 1) {//饼状图
g2.setColor(Color.white);
g2.fillRect(0, 0, dim.width, dim.height);
int total = result[result.length - 1];
int begTangle = 0;
int endTangle = 0;
g2.setColor(Color.black);
int pointx=dim.width/2;//圆心x
int pointy=dim.height/2;//圆心y
int r=150;//半径
long[] pointsx=new long[result.length-1];
long[] pointsy=new long[result.length-1];
pointsx[0]=pointx+r;
pointsy[0]=pointy;
for (int i = 1; i < result.length - 1; i++) {
if (i >= 6) {
g2.setColor(color[i % 6]);
}
else {
g2.setColor(color[i]);
}
if (result[i] > 0) {
int percent=Math.round((result[i]*100f)/total);
endTangle = Math.round(percent*360f/100f);
title[i]=title[i]+"("+percent+"%)";
g2.fillArc( pointx-r,pointy-r, 2*r, 2*r,
begTangle, endTangle);
//新中心点
pointsx[i]=Math.round(Math.cos(Math.toRadians(begTangle+endTangle*0.5))*r+pointx);
pointsy[i]=Math.round(pointy-Math.sin(Math.toRadians(begTangle+endTangle*0.5))*r);
//延长点
long pointsxEx=Math.round(Math.cos(Math.toRadians(begTangle+endTangle*0.5))*(r+50)+pointx);
long pointsyEx=Math.round(pointy-Math.sin(Math.toRadians(begTangle+endTangle*0.5))*(r+50));
g2.setColor(Color.black);
g2.draw(new Line2D.Double(pointsx[i], pointsy[i], pointsxEx, pointsyEx));
//画文本框
g2.setColor(new Color(251,249,206));
if(((int)pointsxEx)<pointx){
g2.fillRect( (int) pointsxEx-110, (int) pointsyEx - 10, 110, 20);
g2.setColor(Color.black);
g2.drawString(title[i],(int)pointsxEx-110,(int)pointsyEx+5);
}
else{
g2.fillRect( (int) pointsxEx, (int) pointsyEx - 10, 110, 20);
g2.setColor(Color.black);
g2.drawString(title[i],(int)pointsxEx,(int)pointsyEx+5);
}
begTangle = begTangle + endTangle;
}
}
}
else {//柱状图
// make sure to fill in the background color
g2.setColor(Color.white);
g2.fillRect(0, 0, dim.width, dim.height);
// draw the x and y axis
g2.setPaint(Color.black);
g2.setStroke(new BasicStroke(2.0f));
g2.draw(new Line2D.Double(10, 10, 10, dim.height - 120));
g2.draw(new Line2D.Double(10, dim.height - 120,
dim.width, dim.height - 120));
//画柱形图
Font font = g2.getFont().deriveFont(12.0f);
g2.setFont(font);
// font.layoutGlyphVector()
int height = Math.round(dim.height - 120 - 30) / result[0];
for (int i = 1; i < result.length - 1; i++) {
g2.setPaint(Color.black);
g2.drawString("" + result[i], 20 + (i - 1) * 30,
dim.height - 120 - height * result[i] - 20);
//draw the title
//print one by one;
for (int j = 1; j <= Math.round(title[i].length() / 2); j++) {
g2.drawString(title[i].substring( (j - 1) * 2, j * 2),
20 + (i - 1) * 30, dim.height - 120 + j * 20);
}
if (i >= 6) {
g2.setColor(color[i % 6]);
}
else {
g2.setColor(color[i]);
}
g2.fillRect(20 + (i - 1) * 30, dim.height - 120 - height * result[i],
20, height * result[i]);
}
}
}
}/*****************program end************************/
3。生成jpg图形并显示：与曲线图中介绍的部分类似，不再赘述。
