Java

[VenomFrogg]

I didn't really know where this would should go at so I put it here.

How do you figure out how to determine whether the input data is an integer or a floating-point data type in Java?

[VenomFrogg]

I didn't really know where this would should go at so I put it here.

How do you figure out how to determine whether the input data is an integer or a floating-point data type in Java?

[freejack]

i´m not sure but i think it´s with typeof

[freejack]

i´m not sure but i think it´s with typeof

[cgkanchi]

I tried it and typeof doesn't work (phew, I thought that java had a keyword that I didn't know of). If you want to determine what kind of value has been input in to a textbox or other string, then do a String.indexOf(".") if any value except -1 is returned, then the value is a float, otherwise, it's an integer. Also, after determining the type of datatype, you might want to do and Integer.parseInt() and a Float.parseFloat() in the appropriate if condition and catch a NumberFormatException, this will prevent users from inputing text.
Cheers,
cgkanchi

[cgkanchi]

I tried it and typeof doesn't work (phew, I thought that java had a keyword that I didn't know of). If you want to determine what kind of value has been input in to a textbox or other string, then do a String.indexOf(".") if any value except -1 is returned, then the value is a float, otherwise, it's an integer. Also, after determining the type of datatype, you might want to do and Integer.parseInt() and a Float.parseFloat() in the appropriate if condition and catch a NumberFormatException, this will prevent users from inputing text.
Cheers,
cgkanchi

[IceStorm]

This is one possible solution, if I understand the question correctly.

Widgets, such as JTextField, read in data as strings. So you can parse it for a decimal point to check for a floating point value. An example might be...


import javax.swing.*;
import java.awt.*;
import java.awt.event.*;


public class findtype extends JFrame
{
private JTextField text1, text2;

private JButton testTypeBtn, clearBtn;

public findtype()
{
super("findtype test");
Container c = getContentPane();
c.setLayout(new FlowLayout());

text1 = new JTextField(10);
text2 = new JTextField(30);

testTypeBtn = new JButton("Test");
clearBtn = new JButton("Clear");

testTypeBtn.addActionListener(new BtnEvnt());
testTypeBtn.addActionListener(new BtnEvnt());

c.add(text1);
c.add(text2);
c.add(testTypeBtn);
c.add(clearBtn);

setBounds(0,0,400,200);
show();
}


public static void main(String args[])
{
new findtype();
}

private class BtnEvnt implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
Object source = e.getSource();

if(source == testTypeBtn)
{
if( text1.getText().toString().indexOf(".") == -1 )
text2.setText("possbily a plain old integer.");
else
text2.setText("possibly a floating point number.");
}
else
{
text1.setText("");
text2.setText("");
}

}
}

}