Thread: Character Count Frequently

Hello, i'm new here. I want create a character count frequently using SWING.

it's my code

import java.awt.BorderLayout;
 
 
public class CharacterCounter extends JFrame {
 
	private JPanel contentPane;
	private JTextField input;
	private JTextArea output;
 
	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					CharacterCounter frame = new CharacterCounter();
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}
 
	/**
	 * Create the frame.
	 */
	public CharacterCounter() {
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 274, 258);
		contentPane = new JPanel();
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
		setContentPane(contentPane);
		contentPane.setLayout(null);
 
		JLabel lblText = new JLabel("Text");
		lblText.setBounds(34, 17, 70, 15);
		contentPane.add(lblText);
 
		input = new JTextField();
		input.setBounds(77, 12, 164, 25);
		contentPane.add(input);
		input.setColumns(10);
 
 
 
		JButton btnCalculate = new JButton("Calculate");
		btnCalculate.addActionListener(new ActionListener() {
 
			public void actionPerformed(ActionEvent arg0) {
 
				String text = input.getText();
				text = text.toLowerCase();
				char [] character =  { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z' };
				int [] freq = new int [character.length];
 
				for ( int i = 0; i < text.length(); i++ ){
					for ( int j = 0; j < character.length; j++ ){
						if ( text.charAt(i) == character [j]) {
							freq[j]++;
						}
					}
				}
				for ( int i = 0; i < freq.length; i++ ){
					if (freq[i] >= 1) {
						output.append(character[i]+"="+ freq[i]+ "\n");
					}
				}
			}
 
			}
		);
		btnCalculate.setBounds(141, 46, 100, 25);
		contentPane.add(btnCalculate);
 
		JTextArea output = new JTextArea();
		output.setBounds(34, 83, 93, 133);
		contentPane.add(output);
	}
}

I've got error message when try to show the character count in text area (variable = output). Anyone can help?

Thank for response my question. this almost resolve, the application using this code

import java.awt.BorderLayout;
import java.awt.EventQueue;
 
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JTextArea;
 
 
public class CharacterCounter extends JFrame {
 
	private JPanel contentPane;
	private JTextField input;
	private JTextArea output;
 
	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					CharacterCounter frame = new CharacterCounter();
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}
 
	/**
	 * Create the frame.
	 */
	public CharacterCounter() {
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 274, 258);
		contentPane = new JPanel();
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
		setContentPane(contentPane);
		contentPane.setLayout(null);
 
		JLabel lblText = new JLabel("Text");
		lblText.setBounds(34, 17, 70, 15);
		contentPane.add(lblText);
 
		input = new JTextField();
		input.setBounds(77, 12, 164, 25);
		contentPane.add(input);
		input.setColumns(10);
 
		output = new JTextArea();
		output.setBounds(34, 83, 93, 133);
 
 
 
		JButton btnCalculate = new JButton("Calculate");
		btnCalculate.addActionListener(new ActionListener() {
 
			public void actionPerformed(ActionEvent arg0) {
 
				String text = input.getText();
				text = text.toLowerCase();
				char [] character =  { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z' };
				int [] frek = new int [character.length];
 
				for ( int i = 0; i < text.length(); i++ ){
					for ( int j = 0; j < character.length; j++ ){
						if ( text.charAt(i) == character [j]) {
							frek[j]++;
						}
					}
				}
				for ( int i = 0; i < frek.length; i++ ){
					if (frek[i] >= 1) {
						output.setText(String.valueOf(frek));
//						output.append(character[i]+"="+ frek[i]+ "\n");
					}
				}
			}
 
			}
		);
		btnCalculate.setBounds(141, 46, 100, 25);
		contentPane.add(btnCalculate);
 
		contentPane.add(output);
	}
}

but if i try to writing "welcome to java" and calculate it the result is there:
009.jpg

I want the result showing every character on every word. Sorry my english not good.