Java Program to Display a Pie Chart Using a Frame

«
»

This is a Java Program to Display a Pie Chart Using a Frame

Problem Description

We have to write a program in Java such that it displays a pie chart for a given data

Expected Input and Output

For displaying a pie chart, we can have the following set of input and output.

advertisement

To View the Pie Chart :

When the program is executed,
it is expected that the frame contains a pie chart.
Problem Solution

1. Create an array of data type int to store the value of each data.
2. Create an array of data type Color to store the desired color in the pie chart for the respective data value.
3. Get the sum of all data values.
4. For each data value, calculate the percentage share in the pie chart.
5. Draw an arc for each data value.
6. Fill the arc with the respective color.

Program/Source Code

Here is source code of the Java Program to create a pie chart. The program is successfully compiled and tested using javac compiler on Fedora 30. The program output is also shown below.

advertisement
  1. /* Java Program to Create a Pie Chart using a Frame */
  2. import java.applet.*;
  3. import java.awt.*;
  4. public class Pie_Chart extends Applet
  5. {
  6.     int[] data_values;
  7.     Color[] data_clr;
  8.     int total;
  9.     //Function to create a data set
  10.     public void init()
  11.     {
  12. 	setBackground(Color.white);
  13. 	//Create a data set to represent in pie-chart
  14. 	data_values=new int[]{10,25,12,15,15,18,5};
  15. 	data_clr=new Color[]{Color.red,Color.blue,Color.green,Color.yellow,
  16.                              Color.orange,Color.black,Color.white};
  17.     }
  18.     //Function to get the sum of all data values
  19.     public void start()
  20.     {
  21. 	int n = data_values.length;
  22. 	int i;
  23. 	total=0;
  24. 	for(i=0;i<n;i++)
  25. 	{
  26. 	    total+=data_values[i];
  27. 	}
  28.     }
  29.     //Function to draw the pie chart
  30.     public void paint(Graphics g)
  31.     {
  32. 	int i;
  33. 	int start_angle = 0;
  34. 	for(i=0;i<data_values.length;i++)
  35. 	{
  36. 	    int arc_angle = (int)(data_values[i]*360 / total);
  37. 	    g.drawArc(100,100,300,300,start_angle,arc_angle);
  38. 	    g.setColor(data_clr[i]);
  39. 	    g.fillArc(100,100,300,300,start_angle,arc_angle);
  40. 	    start_angle+=arc_angle;
  41. 	}
  42.     }
  43. }
  44. /*
  45. <applet code = Pie_Chart.class width=500 height=500>
  46. </applet>
  47. */

To compile an execute the program use the following commands :

>>>javac My_Cursor.java
>>>appletviewer My_Cursor.java
Program Explanation

1. Create arrays to store the data values and color for the respective data.
2. Get the sum of all data values.
3. Get the share of each data in the pie chart usin and draw an arc from the last position of arc to the calculated position.
4. Change the color of arc using setColor method.
5. Fill the arc using fillArc method.

advertisement
Runtime Test Cases

Here’s the run time test cases for creating a pie chart.

Test case – To View the Pie Chart:
java-program-pie-chart

Sanfoundry Global Education & Learning Series – Java Programs.

advertisement
advertisement
advertisement
advertisement
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He is Linux Kernel Developer & SAN Architect and is passionate about competency developments in these areas. He lives in Bangalore and delivers focused training sessions to IT professionals in Linux Kernel, Linux Debugging, Linux Device Drivers, Linux Networking, Linux Storage, Advanced C Programming, SAN Storage Technologies, SCSI Internals & Storage Protocols such as iSCSI & Fiber Channel. Stay connected with him @ LinkedIn