Replace fixed number of symbols in String

-1

I have this number: 4200000000000000
I would like to leave only the first 4 digits and last 3 digits:

42000......000

Everything else should be replaced by dots. How I can implement this with some smart algorithm?

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

Is the input a String? And I'm assuming you want to return a String?

– GBlodgett
Nov 21 '18 at 16:18

Yes - I want String

– Peter Penzov
Nov 21 '18 at 16:20

1

What have you tried? Where are you stuck?

– Nicholas K
Nov 21 '18 at 16:22

add a comment |

-1

I have this number: 4200000000000000
I would like to leave only the first 4 digits and last 3 digits:

42000......000

Everything else should be replaced by dots. How I can implement this with some smart algorithm?

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

Is the input a String? And I'm assuming you want to return a String?

– GBlodgett
Nov 21 '18 at 16:18

Yes - I want String

– Peter Penzov
Nov 21 '18 at 16:20

1

What have you tried? Where are you stuck?

– Nicholas K
Nov 21 '18 at 16:22

add a comment |

-1

I have this number: 4200000000000000
I would like to leave only the first 4 digits and last 3 digits:

42000......000

Everything else should be replaced by dots. How I can implement this with some smart algorithm?

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

I have this number: 4200000000000000
I would like to leave only the first 4 digits and last 3 digits:

42000......000

Everything else should be replaced by dots. How I can implement this with some smart algorithm?

java

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

asked Nov 21 '18 at 16:12

Peter Penzov

14060184389

Is the input a String? And I'm assuming you want to return a String?

– GBlodgett
Nov 21 '18 at 16:18

Yes - I want String

– Peter Penzov
Nov 21 '18 at 16:20

1

What have you tried? Where are you stuck?

– Nicholas K
Nov 21 '18 at 16:22

add a comment |

Is the input a String? And I'm assuming you want to return a String?

– GBlodgett
Nov 21 '18 at 16:18

Yes - I want String

– Peter Penzov
Nov 21 '18 at 16:20

1

What have you tried? Where are you stuck?

– Nicholas K
Nov 21 '18 at 16:22

Is the input a String? And I'm assuming you want to return a String?

– GBlodgett
Nov 21 '18 at 16:18

Yes - I want String

– Peter Penzov
Nov 21 '18 at 16:20

What have you tried? Where are you stuck?

– Nicholas K
Nov 21 '18 at 16:22

add a comment |

6 Answers
6

active

oldest

votes

Why not use a StringBuilder and the substring method:

public static String foo(long num) {

    String numToString = String.valueOf(num);

    return new StringBuilder()

              .append(numToString.substring(0 , 4))

              .append("....")

              .append(numToString.substring(numToString.length()-3, numToString.length()))

              .toString();

}

When inputted 4200000000000000 it outputs:

4200....000

Or if the input is already a String:

public static String foo(String str) {

    return new StringBuilder()

            .append(str.substring(0 , 4))

            .append("....")

            .append(str.substring(str.length()-3, str.length()))

            .toString();

}

edited Nov 21 '18 at 16:29

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

add a comment |

Parse your number into a string and try this:

int last = 3;

int first = 4;

String number = '4200000000000000';

String start = number.substring(0,first-1);

String end = number.substring(number.length()-last,number.length()-1);

String dots = '';



for(int i = 0; i<number.length()-last-first;i++){

  dots = dots + '.';

}



String result = start + dots + end;

answered Nov 21 '18 at 16:27

Silvan

609

add a comment |

You can use something like this,

public class Main {



    public static void main(String args) {

        System.out.println(convert("4200000000000000", 4, 3));

    }



    static String convert(String number, int firstDigits, int lastDigits) {

        String first = number.substring(0, firstDigits);

        String middle = number.substring(firstDigits, number.length() - lastDigits).replaceAll("0", ".");

        String last = number.substring(number.length() - lastDigits, number.length());



        return first + middle + last;

    }

}

answered Nov 21 '18 at 16:27

Sand

1,7182721

add a comment |

You could convert it to a char array, alter it, then convert it back into a string

    char charArray = originalNumber.toCharArray();



    for (int i; i < charArray.length; i++) {

        if (i <= 4 || i >= charArray.length - 3) {

        charArray[i] = ".";

        }

    }

    String outputString = new String(charArray);

answered Nov 21 '18 at 16:28

AleksW

1239

add a comment |

This will replace all chars from the 4th char up to the 4th from the end with '.':

    String start = "4200000000000000";

    System.out.println(start);



    String target = start;

    if (start.length() > 7) {

        target = new StringBuilder()

                .append(start.substring(0, 4))

                .append(new String(new char[start.length() - 7]).replaceAll(".", "."))

                .append(start.substring(start.length() - 3))

                .toString();

    }

    System.out.println(target);

will print

4200000000000000

4200.........000

answered Nov 21 '18 at 16:50

forpas

13.1k3524

add a comment |

Using substring method of the String class :

String str = "4200000000000000";

String res = str.substring(0,4)+ str.substring(4,str.length()-3).replaceAll(".", ".") + str.substring(str.length()-3);

If you are using Apache commons library, you can use repeat method to create masking string of specified length and the overlay method of StringUtils class to overlay part of the String :

String str = "4200000000000000";

String mask= StringUtils.repeat('.', str.length()-7);        

String res = StringUtils.overlay(str, mask, 4, str.length()-3);

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

add a comment |

Your Answer

StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});

}
});

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Post as a guest

Name

Required, but never shown

StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53416211%2freplace-fixed-number-of-symbols-in-string%23new-answer', 'question_page');
}
);

Post as a guest

Name

Required, but never shown

6 Answers
6

active

oldest

votes

6 Answers
6

active

oldest

votes

Why not use a StringBuilder and the substring method:

public static String foo(long num) {

    String numToString = String.valueOf(num);

    return new StringBuilder()

              .append(numToString.substring(0 , 4))

              .append("....")

              .append(numToString.substring(numToString.length()-3, numToString.length()))

              .toString();

}

When inputted 4200000000000000 it outputs:

4200....000

Or if the input is already a String:

public static String foo(String str) {

    return new StringBuilder()

            .append(str.substring(0 , 4))

            .append("....")

            .append(str.substring(str.length()-3, str.length()))

            .toString();

}

edited Nov 21 '18 at 16:29

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

add a comment |

Why not use a StringBuilder and the substring method:

public static String foo(long num) {

    String numToString = String.valueOf(num);

    return new StringBuilder()

              .append(numToString.substring(0 , 4))

              .append("....")

              .append(numToString.substring(numToString.length()-3, numToString.length()))

              .toString();

}

When inputted 4200000000000000 it outputs:

4200....000

Or if the input is already a String:

public static String foo(String str) {

    return new StringBuilder()

            .append(str.substring(0 , 4))

            .append("....")

            .append(str.substring(str.length()-3, str.length()))

            .toString();

}

edited Nov 21 '18 at 16:29

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

add a comment |

Why not use a StringBuilder and the substring method:

public static String foo(long num) {

    String numToString = String.valueOf(num);

    return new StringBuilder()

              .append(numToString.substring(0 , 4))

              .append("....")

              .append(numToString.substring(numToString.length()-3, numToString.length()))

              .toString();

}

When inputted 4200000000000000 it outputs:

4200....000

Or if the input is already a String:

public static String foo(String str) {

    return new StringBuilder()

            .append(str.substring(0 , 4))

            .append("....")

            .append(str.substring(str.length()-3, str.length()))

            .toString();

}

edited Nov 21 '18 at 16:29

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

Why not use a StringBuilder and the substring method:

public static String foo(long num) {

    String numToString = String.valueOf(num);

    return new StringBuilder()

              .append(numToString.substring(0 , 4))

              .append("....")

              .append(numToString.substring(numToString.length()-3, numToString.length()))

              .toString();

}

When inputted 4200000000000000 it outputs:

4200....000

Or if the input is already a String:

public static String foo(String str) {

    return new StringBuilder()

            .append(str.substring(0 , 4))

            .append("....")

            .append(str.substring(str.length()-3, str.length()))

            .toString();

}

edited Nov 21 '18 at 16:29

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

edited Nov 21 '18 at 16:29

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

answered Nov 21 '18 at 16:24

GBlodgett

10.2k42035

add a comment |

Parse your number into a string and try this:

int last = 3;

int first = 4;

String number = '4200000000000000';

String start = number.substring(0,first-1);

String end = number.substring(number.length()-last,number.length()-1);

String dots = '';



for(int i = 0; i<number.length()-last-first;i++){

  dots = dots + '.';

}



String result = start + dots + end;

answered Nov 21 '18 at 16:27

Silvan

609

add a comment |

Parse your number into a string and try this:

int last = 3;

int first = 4;

String number = '4200000000000000';

String start = number.substring(0,first-1);

String end = number.substring(number.length()-last,number.length()-1);

String dots = '';



for(int i = 0; i<number.length()-last-first;i++){

  dots = dots + '.';

}



String result = start + dots + end;

answered Nov 21 '18 at 16:27

Silvan

609

add a comment |

Parse your number into a string and try this:

int last = 3;

int first = 4;

String number = '4200000000000000';

String start = number.substring(0,first-1);

String end = number.substring(number.length()-last,number.length()-1);

String dots = '';



for(int i = 0; i<number.length()-last-first;i++){

  dots = dots + '.';

}



String result = start + dots + end;

answered Nov 21 '18 at 16:27

Silvan

609

Parse your number into a string and try this:

int last = 3;

int first = 4;

String number = '4200000000000000';

String start = number.substring(0,first-1);

String end = number.substring(number.length()-last,number.length()-1);

String dots = '';



for(int i = 0; i<number.length()-last-first;i++){

  dots = dots + '.';

}



String result = start + dots + end;

answered Nov 21 '18 at 16:27

Silvan

609

answered Nov 21 '18 at 16:27

Silvan

609

answered Nov 21 '18 at 16:27

Silvan

609

answered Nov 21 '18 at 16:27

Silvan

609

add a comment |

You can use something like this,

public class Main {



    public static void main(String args) {

        System.out.println(convert("4200000000000000", 4, 3));

    }



    static String convert(String number, int firstDigits, int lastDigits) {

        String first = number.substring(0, firstDigits);

        String middle = number.substring(firstDigits, number.length() - lastDigits).replaceAll("0", ".");

        String last = number.substring(number.length() - lastDigits, number.length());



        return first + middle + last;

    }

}

answered Nov 21 '18 at 16:27

Sand

1,7182721

add a comment |

You can use something like this,

public class Main {



    public static void main(String args) {

        System.out.println(convert("4200000000000000", 4, 3));

    }



    static String convert(String number, int firstDigits, int lastDigits) {

        String first = number.substring(0, firstDigits);

        String middle = number.substring(firstDigits, number.length() - lastDigits).replaceAll("0", ".");

        String last = number.substring(number.length() - lastDigits, number.length());



        return first + middle + last;

    }

}

answered Nov 21 '18 at 16:27

Sand

1,7182721

add a comment |

You can use something like this,

public class Main {



    public static void main(String args) {

        System.out.println(convert("4200000000000000", 4, 3));

    }



    static String convert(String number, int firstDigits, int lastDigits) {

        String first = number.substring(0, firstDigits);

        String middle = number.substring(firstDigits, number.length() - lastDigits).replaceAll("0", ".");

        String last = number.substring(number.length() - lastDigits, number.length());



        return first + middle + last;

    }

}

answered Nov 21 '18 at 16:27

Sand

1,7182721

You can use something like this,

public class Main {



    public static void main(String args) {

        System.out.println(convert("4200000000000000", 4, 3));

    }



    static String convert(String number, int firstDigits, int lastDigits) {

        String first = number.substring(0, firstDigits);

        String middle = number.substring(firstDigits, number.length() - lastDigits).replaceAll("0", ".");

        String last = number.substring(number.length() - lastDigits, number.length());



        return first + middle + last;

    }

}

answered Nov 21 '18 at 16:27

Sand

1,7182721

answered Nov 21 '18 at 16:27

Sand

1,7182721

answered Nov 21 '18 at 16:27

Sand

1,7182721

answered Nov 21 '18 at 16:27

Sand

1,7182721

add a comment |

You could convert it to a char array, alter it, then convert it back into a string

    char charArray = originalNumber.toCharArray();



    for (int i; i < charArray.length; i++) {

        if (i <= 4 || i >= charArray.length - 3) {

        charArray[i] = ".";

        }

    }

    String outputString = new String(charArray);

answered Nov 21 '18 at 16:28

AleksW

1239

add a comment |

You could convert it to a char array, alter it, then convert it back into a string

    char charArray = originalNumber.toCharArray();



    for (int i; i < charArray.length; i++) {

        if (i <= 4 || i >= charArray.length - 3) {

        charArray[i] = ".";

        }

    }

    String outputString = new String(charArray);

answered Nov 21 '18 at 16:28

AleksW

1239

add a comment |

You could convert it to a char array, alter it, then convert it back into a string

    char charArray = originalNumber.toCharArray();



    for (int i; i < charArray.length; i++) {

        if (i <= 4 || i >= charArray.length - 3) {

        charArray[i] = ".";

        }

    }

    String outputString = new String(charArray);

answered Nov 21 '18 at 16:28

AleksW

1239

You could convert it to a char array, alter it, then convert it back into a string

    char charArray = originalNumber.toCharArray();



    for (int i; i < charArray.length; i++) {

        if (i <= 4 || i >= charArray.length - 3) {

        charArray[i] = ".";

        }

    }

    String outputString = new String(charArray);

answered Nov 21 '18 at 16:28

AleksW

1239

answered Nov 21 '18 at 16:28

AleksW

1239

answered Nov 21 '18 at 16:28

AleksW

1239

answered Nov 21 '18 at 16:28

AleksW

1239

add a comment |

This will replace all chars from the 4th char up to the 4th from the end with '.':

    String start = "4200000000000000";

    System.out.println(start);



    String target = start;

    if (start.length() > 7) {

        target = new StringBuilder()

                .append(start.substring(0, 4))

                .append(new String(new char[start.length() - 7]).replaceAll(".", "."))

                .append(start.substring(start.length() - 3))

                .toString();

    }

    System.out.println(target);

will print

4200000000000000

4200.........000

answered Nov 21 '18 at 16:50

forpas

13.1k3524

add a comment |

This will replace all chars from the 4th char up to the 4th from the end with '.':

    String start = "4200000000000000";

    System.out.println(start);



    String target = start;

    if (start.length() > 7) {

        target = new StringBuilder()

                .append(start.substring(0, 4))

                .append(new String(new char[start.length() - 7]).replaceAll(".", "."))

                .append(start.substring(start.length() - 3))

                .toString();

    }

    System.out.println(target);

will print

4200000000000000

4200.........000

answered Nov 21 '18 at 16:50

forpas

13.1k3524

add a comment |

This will replace all chars from the 4th char up to the 4th from the end with '.':

    String start = "4200000000000000";

    System.out.println(start);



    String target = start;

    if (start.length() > 7) {

        target = new StringBuilder()

                .append(start.substring(0, 4))

                .append(new String(new char[start.length() - 7]).replaceAll(".", "."))

                .append(start.substring(start.length() - 3))

                .toString();

    }

    System.out.println(target);

will print

4200000000000000

4200.........000

answered Nov 21 '18 at 16:50

forpas

13.1k3524

This will replace all chars from the 4th char up to the 4th from the end with '.':

    String start = "4200000000000000";

    System.out.println(start);



    String target = start;

    if (start.length() > 7) {

        target = new StringBuilder()

                .append(start.substring(0, 4))

                .append(new String(new char[start.length() - 7]).replaceAll(".", "."))

                .append(start.substring(start.length() - 3))

                .toString();

    }

    System.out.println(target);

will print

4200000000000000

4200.........000

answered Nov 21 '18 at 16:50

forpas

13.1k3524

answered Nov 21 '18 at 16:50

forpas

13.1k3524

answered Nov 21 '18 at 16:50

forpas

13.1k3524

answered Nov 21 '18 at 16:50

forpas

13.1k3524

add a comment |

Using substring method of the String class :

String str = "4200000000000000";

String res = str.substring(0,4)+ str.substring(4,str.length()-3).replaceAll(".", ".") + str.substring(str.length()-3);

If you are using Apache commons library, you can use repeat method to create masking string of specified length and the overlay method of StringUtils class to overlay part of the String :

String str = "4200000000000000";

String mask= StringUtils.repeat('.', str.length()-7);        

String res = StringUtils.overlay(str, mask, 4, str.length()-3);

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

add a comment |

Using substring method of the String class :

String str = "4200000000000000";

String res = str.substring(0,4)+ str.substring(4,str.length()-3).replaceAll(".", ".") + str.substring(str.length()-3);

If you are using Apache commons library, you can use repeat method to create masking string of specified length and the overlay method of StringUtils class to overlay part of the String :

String str = "4200000000000000";

String mask= StringUtils.repeat('.', str.length()-7);        

String res = StringUtils.overlay(str, mask, 4, str.length()-3);

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

add a comment |

Using substring method of the String class :

String str = "4200000000000000";

String res = str.substring(0,4)+ str.substring(4,str.length()-3).replaceAll(".", ".") + str.substring(str.length()-3);

If you are using Apache commons library, you can use repeat method to create masking string of specified length and the overlay method of StringUtils class to overlay part of the String :

String str = "4200000000000000";

String mask= StringUtils.repeat('.', str.length()-7);        

String res = StringUtils.overlay(str, mask, 4, str.length()-3);

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

Using substring method of the String class :

String str = "4200000000000000";

String res = str.substring(0,4)+ str.substring(4,str.length()-3).replaceAll(".", ".") + str.substring(str.length()-3);

If you are using Apache commons library, you can use repeat method to create masking string of specified length and the overlay method of StringUtils class to overlay part of the String :

String str = "4200000000000000";

String mask= StringUtils.repeat('.', str.length()-7);        

String res = StringUtils.overlay(str, mask, 4, str.length()-3);

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

answered Nov 21 '18 at 16:53

Eritrean

3,4321914

add a comment |

draft saved

draft discarded

Thanks for contributing an answer to Stack Overflow!

Please be sure to answer the question. Provide details and share your research!

But avoid …

Asking for help, clarification, or responding to other answers.

Making statements based on opinion; back them up with references or personal experience.

To learn more, see our tips on writing great answers.

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Post as a guest

Name

Required, but never shown

Post as a guest

Name

Required, but never shown

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Post as a guest

Name

Required, but never shown

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Post as a guest

Name

Required, but never shown

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Post as a guest

Name

Required, but never shown

Name

Required, but never shown

Name

Required, but never shown

This page is only for reference, If you need detailed information, please check here

Search This Blog

Ufyukyu