Force the user to add only Hebrew letters

Question

How can I make a JTextfield accept only Hebrew letters with if statement? I can do a long if statement with all the Hebrew letters but it will not look good.
I found out that the Unicode of Hebrew first letter is \u05D0 and last one is \u05EA.
How can I say that if the gettext is in between these 2 letters so show (meaning to check if the text entered is only a Hebrew letter), the user will add only one letter in each textfield.
Thank you in advance

Do you mean `if (0x05D0 <= ch && ch <= 0x05EA)` to check it is ok. — Peter Lawrey, May 07 '16 at 15:38

score 3 · Answer 1 · edited May 23 '17 at 11:52

3

Build an input validator with your validation logic, and attach it to your textField to verify input as you enter it. Steps: Combine the validation logic given by @peter-lawray with the mechanism of building an input verifier and you're good to go.

edited May 23 '17 at 11:52

Community

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1

answered May 07 '16 at 15:52

mohsenmadi

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@mohsenmadi Thank you so much, but I feel this is a little more advanced for me – Aboelmagd Saad May 07 '16 at 16:31
No problem :-). If I were you and you are new to all this, I would invest the time into learning JavaFX if you want to build desktop apps. JavaFX is the new GUI framework. – mohsenmadi May 07 '16 at 17:43

score 2 · Answer 2 · answered May 07 '16 at 15:53

2

You could use a simple one-liner using a Stream

boolean valid = jTextField.getText().chars().allMatch(p -> p <= 0x05ea && p >= 0x05d0);

answered May 07 '16 at 15:53

Mad Matts

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score 1 · Answer 3 · answered May 07 '16 at 16:40

Putting the other answers together, this is an input validator you could use:

// adapted from mohsenmadi/Daniel Rikowski
public class HebrewVerifier extends InputVerifier {
    @Override
    public boolean verify(JComponent input) {
        String text = ((JTextField) input).getText();
        // method suggested by Mad Matts
        return text.chars().allMatch(p -> p <= 0x05ea && p >= 0x05d0);
    }
}

And then you simply need to attach it to your JTextField:

myHebrewTextField.setInputVerifier(new HebrewVerifier());

java8.being · Accepted Answer · 2016-05-07T16:55:15.333

0

Since you are using JTextField and this class inherits getText() method which returns a String. So, this is how I will probably do it.

String name = jTextField.getText();
char[] charArray = name.toCharArray();
for (char c : charArray) {
    if (!(c <= 0x05ea && c >= 0x05d0)) {
        break;
        //valid
    }
}

This can become more efficient, if you keep the counter of elements added/removed, you only will have to check the latest entered character (in case of removal you probably won't need that but that scenario will need more coding, so I hope you will figure that out once you solves this issue).

Update:

This is what I have tried:

        String name      = "אבגa";
        char[] charArray = name.toCharArray();
        for (char c : charArray) {
            if (c <= 0x05ea && c >= 0x05d0) {
                System.out.println("Valid hebrew");
            }
        }

And this prints Valid hebrew three times.

edited May 07 '16 at 16:55

answered May 07 '16 at 15:44

java8.being

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Thank you really. But some reasons it doesn't work for me ! Can we make the char String ? – Aboelmagd Saad May 07 '16 at 16:01
I tried it but it seems the check is not done ` if (btn.getSelectedItem().equals("\u05E2\u05D1\u05E8")) { String first; Swing get = new Swing(); first = get.getfl(); char [] charArray = first.toCharArray(); for(char c : charArray) { if (c <= 0x05ea && c >= 0x05d0) { JOptionPane.showMessageDialog(null, "error"); } }` – Aboelmagd Saad May 07 '16 at 16:11
@AboelmagdSaad Can you tell me the input you have in your textfield? – java8.being May 07 '16 at 16:12
sure, I tried with english letters like (a or b) and then went to the combobox and chose the first action I want , and no errors happened at all – Aboelmagd Saad May 07 '16 at 16:14
@AboelmagdSaad Check the updated answer. Code is checking for valid herbrew characters. If these are valid, it will go inside the `if` otherwise, not. – java8.being May 07 '16 at 16:16
I knew the error :D I missed to add != if (!(c <= 0x05ea && c >= 0x05d0)) Now it works – Aboelmagd Saad May 07 '16 at 16:19
done :) Thank you so much But can we run the check only one time, because for now, the error message appears twice for me and not only one time ! – Aboelmagd Saad May 07 '16 at 16:26
Updated the answer to validate once. @AboelmagdSaad – java8.being May 07 '16 at 16:55

score 0 · Answer 5 · answered Oct 12 '22 at 07:03

import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.logging.Level;
import java.util.logging.Logger;
//...
 public static String readHebrewString()
    {
        String str="";
        System.out.println("הקלד שורה");      
        InputStreamReader in;
        try {
            char[]buffer=new char[1024];
            in = new InputStreamReader(System.in, "Windows-1255");
            in.read(buffer);
            int i=0;
            while((int)buffer[i]!=10)
                  str+=buffer[i++];
        } catch (UnsupportedEncodingException ex) {
            Logger.getLogger(Demo001.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(Demo001.class.getName()).log(Level.SEVERE, null, ex);
        }
        return str;
    }

Every time you use `+=` on `str`, a new `string` object is created. The memory consumption of your loop is the amount of characters squared and then divided by 2. — Peter Bruins, Oct 17 '22 at 12:48

Force the user to add only Hebrew letters

5 Answers5