Java applet program for calculator

Write a Java program that works as a simple calculator. Use a grid layout to arrange buttons for the digits and for the + – * % operations. Add a text field to display the result.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
 
/* 
<applet code="Cal" width=300 height=300>
</applet>
*/
 
public class Cal extends Applet
implements ActionListener
{
	String msg=" ";
	int v1,v2,result;
	TextField t1;
	Button b[]=new Button[10];
	Button add,sub,mul,div,clear,mod,EQ;
	char OP;
	public void init()
	{
		Color k=new Color(120,89,90);
		setBackground(k);
		t1=new TextField(10);
		GridLayout gl=new GridLayout(4,5);
		setLayout(gl);
		for(int i=0;i<10;i++)
		{
			b[i]=new Button(""+i);
		}
		add=new Button("add");
		sub=new Button("sub");
		mul=new Button("mul");
		div=new Button("div");
		mod=new Button("mod");
		clear=new Button("clear");
		EQ=new Button("EQ");
		t1.addActionListener(this);
		add(t1);
		for(int i=0;i<10;i++)
		{
			add(b[i]);
		}
		add(add);
		add(sub);
		add(mul);
		add(div);
		add(mod);
		add(clear);
		add(EQ);
		for(int i=0;i<10;i++)
		{
			b[i].addActionListener(this);
		}
		add.addActionListener(this);
		sub.addActionListener(this);
		mul.addActionListener(this);
		div.addActionListener(this);
		mod.addActionListener(this);
		clear.addActionListener(this);
		EQ.addActionListener(this);
	}
 
	public void actionPerformed(ActionEvent ae)
	{
		String str=ae.getActionCommand();
		char ch=str.charAt(0);
		if ( Character.isDigit(ch))
		t1.setText(t1.getText()+str);
		else
		if(str.equals("add"))
		{
			v1=Integer.parseInt(t1.getText());
			OP='+';
			t1.setText("");
		}
		else if(str.equals("sub"))
		{
			v1=Integer.parseInt(t1.getText());
			OP='-';
			t1.setText("");
		}
		else if(str.equals("mul"))
		{
			v1=Integer.parseInt(t1.getText());
			OP='*';
			t1.setText("");
		}
		else if(str.equals("div"))
		{
			v1=Integer.parseInt(t1.getText());
			OP='/';
			t1.setText("");
		}
		else if(str.equals("mod"))
		{
			v1=Integer.parseInt(t1.getText());
			OP='%';
			t1.setText("");
		}
		if(str.equals("EQ"))
		{
			v2=Integer.parseInt(t1.getText());
			if(OP=='+')
				result=v1+v2;
			else if(OP=='-')
				result=v1-v2;
			else if(OP=='*')
				result=v1*v2;
			else if(OP=='/')
				result=v1/v2;
			else if(OP=='%')
				result=v1%v2;
			t1.setText(""+result);
		}	
		if(str.equals("clear"))
		{
			t1.setText("");
		}
	}
}

Output:

Java program base calculator output
Java program base calculator output


78 Responses to “Java applet program for calculator”

    • Markusmccullan

      Java applet program does’nt have main method.we just over write the predefined method

      Reply
    • applet never has a main method… its got its own set of functions and methods

      Reply
  1. Abhinav

    i got an error in public class Cal
    “Cal is not abstract and doesn’t overrude abstract method actionPerformed (ActionEvent) in ActionListener”

    Reply
    • you need to override this method in your class since it is abstract. methods of abstract classes needs to be overidden.

      Reply
    • you need to override this method in your class since it is abstract. methods of abstract classes needs to be overridden.

      Reply

Leave a Reply