Changing the integer in the String in Java

Question

I need to change the string by decreasing the number by one e.g. 011 then 010 etc. if 009 then 008.

However, I cannot think of the ways to do this thing please help me:

<img width="188" height="307" src="File1.files/image006.png" alt="NNMF_Input.png" v:shapes="image_x0020_33" />
<img width="506" height="200" src="File1.files/image014.png" v:shapes="image_x0020_1" />
<img width="506" height="411" src="File1.files/image016.png" v:shapes="image_x0020_2" />
<img width="515" height="179" src="File1.files/image018.png" v:shapes="image_x0020_3" />

Here, I want to change files/image006.png to files/image005.png and change say files/image010.png to files/image009.png.

P.S. They are all in strings! not HTML tags in fact

One Way is: a). Convert String to Integer, b). Decrement Integer, c). Convert back to String. — Rohit Jain
– Rohit Jain, Commented Feb 6, 2014 at 7:27
Yeah but the thing is that I can do that but the problem is I have to extract the part of the string and then put it back to where it was.. and it is 000 thing so it is not just 18 17 thing. — user3278450
– user3278450, Commented Feb 6, 2014 at 7:28
And use DecimalFormat to get the result formatted just the way you want it. — Patricia Shanahan
– Patricia Shanahan, Commented Feb 6, 2014 at 7:31
That is unsatisfactory since I want to automate this (not just them but say 100 of them) — user3278450
– user3278450, Commented Feb 6, 2014 at 7:32
Do you really want to do that in Java or did you mean Javascript? Asking because of HTML code. — Ocaso Protal
– Ocaso Protal, Commented Feb 6, 2014 at 7:36

Evgeniy Dorofeev · Accepted Answer · 2014-02-06 07:41:26Z

6

try regex

    Matcher m = Pattern.compile("(?<=/image)\\d{3}").matcher(str);
    StringBuffer sb = new StringBuffer();
    while(m.find()) {
        m.appendReplacement(sb, String.format("%03d", Integer.parseInt(m.group()) - 1));
    }
    m.appendTail(sb);

answered Feb 6, 2014 at 7:41

Evgeniy Dorofeev

137k31 gold badges209 silver badges288 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

user3278450 Over a year ago

Hi, I am pretty new to regex. Could you please tell me how I would get just the File1.files/image006.png from an img tag using Regex?

Some guy Over a year ago

@user3278450 You can find the basic Regex tutorial here : vogella.com/tutorials/JavaRegularExpressions/article.html

user3278450 Over a year ago

mmm.. I do not know how to add more rules with the current regex in compile for example, ^"src=" .png"$ (but I want to exclude them ..please help me!)

aasu · Accepted Answer · 2014-02-06 07:41:44Z

0

int i = Integer.parseInt("011");
System.out.format("%03d", i-1);

answered Feb 6, 2014 at 7:41

aasu

4724 silver badges13 bronze badges

Comments

Andrzej Jozwik · Accepted Answer · 2014-02-06 07:48:00Z

0

Just for funny - scala solution :)

scala> def increment(str:String) = str.split("[^0-9]").
filter( s => s.nonEmpty && s.length >1).
foldLeft(str)((acc,curr) => acc.replace(curr, {val res = (curr.toInt+1).toString;Range(0,curr.length - res.length).
foldLeft(res)((acc,curr)=> "0"+acc) }))
increment: (str: String)String

scala> increment("File1.files/image014.png")
res10: String = File1.files/image015.png

answered Feb 6, 2014 at 7:48

Andrzej Jozwik

14.8k3 gold badges61 silver badges70 bronze badges

Comments

Saj · Accepted Answer · 2014-02-06 07:57:51Z

String str = "000110";

// Get the last index and add 1 to determine number of leading zeros
int i = str.lastIndexOf('0') + 1;

// Subtract or do any math on the number you want
int newNumber = Integer.parseInt(str) - 1;

// Format the new string with leading zeros
String newString = String.format("%0" + i + "d", newNumber);

// See the new string
System.out.println(newString);

EDIT

To answer your edited question:

String str = "image0110";

// Get the number (above example 0110) from original string using the last character 'e 'from 'image'
str = str.substring(str.lastIndexOf('e') + 1);

// Get how many leading zeros are in there
int i = str.lastIndexOf('0') + 1;

// Do the math
int newNumber = Integer.parseInt(str) - 1;

// Form the new string starting with 'image' and leading zeros
String newString = "image" + String.format("%0" + i + "d", newNumber);

System.out.println(newString);

Collectives™ on Stack Overflow

Changing the integer in the String in Java

4 Answers 4

3 Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

3 Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related