Java - Large String need to split with different field length

Question

I'm new to Java and didn't find any exact solution for my scenario. I have a large string which is 1500 length.

For example : String inData = "THISKALJSKAJFDSKJDKSJ KSJDLKJSFKD LSKJDFKSJ, ASA:..";

I have a fixed format for these 1500 length. I have to split the string into 200+ fields based on each field fixed length. I found something like below.

String firstFld = inData.substring(0, 2);

String secondFld = inData.substring(3, 10);

String thirdFld = inData.substring(11, 13);

can anyone please suggest with better way of doing the split instead of declaring 200 string variables and store them there or loading them to a String Array ? I plan to to build an xml with all these fields after getting them.

I appreciate all your help!

What is the fixed format? Is it stored anywhere in your code? — Blue Boy
– Blue Boy, Commented Mar 21, 2017 at 20:26
Maybe try to learn the basics (arrays, collections etc.) before you start working with XML. — Kayaman
– Kayaman, Commented Mar 21, 2017 at 20:28
the fixed length is stored in a file. I understand I could add this to an array. But if there any other better options ? I updated the question to include the string array as an option. — skcvr
– skcvr, Commented Mar 21, 2017 at 20:34

lucianohgo · Accepted Answer · 2017-03-21 20:45:05Z

1

Well, if it's two of the below, then this would work:

There's a pattern for the field lengths: like (0,2), (3, 10), (11,13), (14, 21) ...
You have a list of field lengths

In both cases it is pretty simple to solve what you want:

First Case: Pattern is 2 chars -> 7 chars starting with 2

String[] fields = new String[getNumberOfFields(1500)];
int curr = 0;
for(int i = 0 ; i < fields.length; i++) {
    if(i % 2 == 0) {
        fields[i] = inData.substring(curr, curr+7);
        curr+=8;
    } else {
        fields[i] = inData.substring(curr, curr+2);
        curr+=3;
    }
}

Second Case: You have a bunch of different field lenghts

int curr = 0;
String[] fields = new String[fieldLengths.length];
for(int i = 0; i < fieldLengths.length; i++) {
     fields[i] = inData.substring(curr, curr+fieldLengths[i]);
}

answered Mar 21, 2017 at 20:45

lucianohgo

3191 silver badge9 bronze badges

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

1 Comment

lucianohgo Over a year ago

If the pattern is more complex though, I would implement it a different way, dependent on how complex and on what it was.

Collectives™ on Stack Overflow

Java - Large String need to split with different field length

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related