Character counter using Java Swing and String api

A simple swing application that is used to count the characters, words and sentences.
User interface is developed by using Java swing api and characters, words and sentences count logic is done by using the String api using various methods like:

• lenght()                     Returns the length of this string.
• Split(String regex)   Splits this string around matches of the given regular expression.
• charAt(int index)     Returns the char value at the specified index.

 Output : 

GUI Code : 

 import javax.swing.*;
 public class CharacterCalculateJFrame extends JFrame {
    public CharacterCalculateJFrame() {
        this.setTitle("Character Counter");
        initComponents();
    }
    @SuppressWarnings("unchecked")
    private void initComponents() {
        jLabel1 = new javax.swing.JLabel();
        jScrollPane1 = new javax.swing.JScrollPane();
        characterTextArea = new javax.swing.JTextArea();
        jLabel2 = new javax.swing.JLabel();
        calculateButton = new javax.swing.JButton();
        jLabel3 = new javax.swing.JLabel();
        charCounterLabel = new javax.swing.JLabel();
        jLabel4 = new javax.swing.JLabel();
        wordLabel = new javax.swing.JLabel();
        jLabel5 = new javax.swing.JLabel();
        sentenceLabel = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jLabel1.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        jLabel1.setForeground(new java.awt.Color(51, 51, 255));
        jLabel1.setText("Character Counter");

        characterTextArea.setColumns(20);
        characterTextArea.setRows(5);
        jScrollPane1.setViewportView(characterTextArea);

        jLabel2.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        jLabel2.setText("Enter Paragraph");

        calculateButton.setFont(new java.awt.Font("Tahoma", 1, 11)); // NOI18N
        calculateButton.setText("Calculate");
        calculateButton.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                calculateButtonActionPerformed(evt);
            }
        });

        jLabel3.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        jLabel3.setText("Characters are :");

        charCounterLabel.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        charCounterLabel.setForeground(new java.awt.Color(51, 51, 255));

        jLabel4.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        jLabel4.setText("Words are :");

        wordLabel.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        wordLabel.setForeground(new java.awt.Color(51, 51, 255));

        jLabel5.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        jLabel5.setText("Sentences are :");

        sentenceLabel.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        sentenceLabel.setForeground(new java.awt.Color(51, 51, 255));

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(43, 43, 43)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                    .addComponent(calculateButton)
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(jLabel2)
                        .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 272, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(jLabel1)))
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                                .addComponent(jLabel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                .addComponent(jLabel4, javax.swing.GroupLayout.PREFERRED_SIZE, 107, javax.swing.GroupLayout.PREFERRED_SIZE))
                            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                                .addComponent(sentenceLabel, javax.swing.GroupLayout.PREFERRED_SIZE, 58, javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                                    .addComponent(jLabel5, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                    .addGroup(javax.swing.GroupLayout.Alignment.LEADING, layout.createSequentialGroup()
                                        .addGap(36, 36, 36)
                                        .addComponent(wordLabel, javax.swing.GroupLayout.PREFERRED_SIZE, 60, javax.swing.GroupLayout.PREFERRED_SIZE))))))
                    .addGroup(layout.createSequentialGroup()
                        .addGap(38, 38, 38)
                        .addComponent(charCounterLabel, javax.swing.GroupLayout.PREFERRED_SIZE, 55, javax.swing.GroupLayout.PREFERRED_SIZE)))
                .addContainerGap(20, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(36, 36, 36)
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 31, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(18, 18, 18)
                .addComponent(jLabel2)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 219, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addComponent(jLabel3)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(charCounterLabel, javax.swing.GroupLayout.PREFERRED_SIZE, 24, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(14, 14, 14)
                        .addComponent(jLabel4)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(wordLabel, javax.swing.GroupLayout.PREFERRED_SIZE, 27, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(15, 15, 15)
                        .addComponent(jLabel5)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(sentenceLabel, javax.swing.GroupLayout.PREFERRED_SIZE, 28, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(18, 18, 18)))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(calculateButton, javax.swing.GroupLayout.PREFERRED_SIZE, 33, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(57, Short.MAX_VALUE))
        );

        pack();
    }
    private void calculateButtonActionPerformed(java.awt.event.ActionEvent evt) {
        String charString = this.characterTextArea.getText().trim();
        this.charCounterLabel.setText(""+charString.length());
        String words[] = charString.split("\\s");
        this.wordLabel.setText(""+words.length);
        int sentenceCounter = 0;
        for(int i=0; i<charString.length(); i++) {
            if(charString.charAt(i)=='.') {
                sentenceCounter++;
            }
        }
        this.sentenceLabel.setText(""+sentenceCounter);    
    }
    public static void main(String args[]) {
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(CharacterCalculateJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(CharacterCalculateJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(CharacterCalculateJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(CharacterCalculateJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        java.awt.EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                new CharacterCalculateJFrame().setVisible(true);
            }
        });
    }
    private javax.swing.JButton calculateButton;
    private javax.swing.JLabel charCounterLabel;
    private javax.swing.JTextArea characterTextArea;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JLabel jLabel5;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JLabel sentenceLabel;
    private javax.swing.JLabel wordLabel;
 }