I have a JTextField in a JApplet with a ActionListener. I compiled it using Eclipse and it works fine. But when I try to load it in a .html file using applet, the JTextField does not register/recognize the ENTER key when I press it. It seems like the ActionListener did not work. I used:
public void init() {
textField = new JTextField(20);
textField.setText("Enter your question here.");
textField.selectAll();
textField.addActionListener(this);
textArea = new JTextArea(10, 20);
textArea.setEditable(false);
JScrollPane scrollPane = new JScrollPane(textArea,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
// Add Components to the Applet.
GridBagLayout gridBag = new GridBagLayout();
Container contentPane = getContentPane();
contentPane.setLayout(gridBag);
GridBagConstraints c = new GridBagConstraints();
c.gridwidth = GridBagConstraints.REMAINDER;
c.fill = GridBagConstraints.HORIZONTAL;
gridBag.setConstraints(textField, c);
contentPane.add(textField);
c.fill = GridBagConstraints.BOTH;
c.weightx = 1.0;
c.weighty = 1.0;
gridBag.setConstraints(scrollPane, c);
contentPane.add(scrollPane);
newline = System.getProperty("line.separator");
}
public void actionPerformed(ActionEvent event) {
String text = textField.getText();
String question = "";
String answer = "";
question = textField.getText();
question = ProcessString(question);
answer = Answer(question);
textArea.append(text + newline);
textArea.append(answer + newline);
textField.selectAll();
}
static String noAnswer;
static boolean knowAnswer = true;
// process the question string, take out non-ACSII characters, spaces, to
// lower space
public String ProcessString(String question) {
question = question.toLowerCase();
String[] words = question.split("\\s+");
question = "";
for (int wordCount = 0; wordCount < words.length; wordCount++) {
words[wordCount] = words[wordCount].replaceAll("[^A-Za-z]", "");
if (wordCount != words.length - 1)
question = question + words[wordCount] + " ";
else
question = question + words[wordCount];
// System.out.println(words[wordCount]);
}
return question;
}
public String Answer(String question) {
String answer = "";
/*
if the database know the answer (did not not know), then return the
answer. if the database does not know the answer, then recover the
answer in database.
*/
if (knowAnswer == true) {
// open the database file and search if questions matches any one in
// the
// database
Scanner sc = null;
try {
sc = new Scanner(new File("database.txt"));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
int answerFrequency = 0;
boolean matchFound = false;
while (sc.hasNext()) {
int questionCount = sc.nextInt();
String line = sc.nextLine();
String[] databaseLine = line.split("\\s+");
String databaseQuestion = "";
String databaseAnswer = "";
// collect words for database questions
for (int wordCount = 1; wordCount <= questionCount; wordCount++) {
if (wordCount != questionCount)
databaseQuestion = databaseQuestion
+ databaseLine[wordCount] + " ";
else
databaseQuestion = databaseQuestion
+ databaseLine[wordCount];
}
// collect words for database answer
for (int wordCount = questionCount + 2; wordCount < databaseLine.length; wordCount++) {
databaseAnswer = databaseAnswer + databaseLine[wordCount]
+ " ";
}
// if the question is found in database, print answer
if (question.equals(databaseQuestion)) {
matchFound = true;
// the current answer is more frequency than the previous
// found
// answer, reassign the current answer the find answer
if (answerFrequency < Integer
.parseInt(databaseLine[questionCount + 1])) {
answerFrequency = Integer
.parseInt(databaseLine[questionCount + 1]);
answer = databaseAnswer;
}
}
}
if (matchFound == true) {
// System.out.println(answer);
knowAnswer = true;
} else {
// System.out.println("I don't know what you mean. How should I answer your question?");
knowAnswer = false;
noAnswer = question;
answer = "I don't know how to respond. How should I answer that?";
}
sc.close();
} else if (knowAnswer == false) {
String[] word = noAnswer.split(" ");
BufferedWriter writer = null;
answer = question;
try {
writer = new BufferedWriter(
new FileWriter("database.txt", true));
writer.newLine();
writer.write(word.length + " " + noAnswer + " 1 " + answer);
} catch (IOException e) {
} finally {
try {
if (writer != null)
writer.close();
} catch (IOException e) {
System.out.println("Cannot write to file");
}
}
answer = "I got that.";
knowAnswer = true;
}
return answer;
}
Really appreciate the help.
This seems to work for me....
public class TestApplet04 extends JApplet implements ActionListener {
private JTextField textField;
private JTextArea textArea;
private String newline;
public void init() {
textField = new JTextField(20);
textField.setText("Enter your question here.");
textField.selectAll();
textField.addActionListener(this);
textArea = new JTextArea(10, 20);
textArea.setEditable(false);
JScrollPane scrollPane = new JScrollPane(textArea,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
// Add Components to the Applet.
GridBagLayout gridBag = new GridBagLayout();
Container contentPane = getContentPane();
contentPane.setLayout(gridBag);
GridBagConstraints c = new GridBagConstraints();
c.gridwidth = GridBagConstraints.REMAINDER;
c.fill = GridBagConstraints.HORIZONTAL;
gridBag.setConstraints(textField, c);
contentPane.add(textField);
c.fill = GridBagConstraints.BOTH;
c.weightx = 1.0;
c.weighty = 1.0;
gridBag.setConstraints(scrollPane, c);
contentPane.add(scrollPane);
newline = System.getProperty("line.separator");
}
public void actionPerformed(ActionEvent event) {
String text = textField.getText();
String question = "";
String answer = "";
question = textField.getText();
// question = ProcessString(question);
// answer = Answer(question);
textArea.append(text + newline);
textArea.append(answer + newline);
textField.selectAll();
}
}
Updated after feedback
Here's you major problem...
sc = new Scanner(new File("database.txt"));
This is going to cause you a number of problems. First of all, the applet isn't likely to have access rights to read from the client machine, so you're likely to run into a security exception. Secondly, as the previous statement may have suggested, the file ins't likely to exist on the client machine.
You need to embed this resource within the Jar of your application and use getClass().getResource("...") to gain access to it. This will return a URL, from which you can use URL#openConnection to gain access to a InputStream, which can use in your scanner.