Parsing lengthy string in Java

Question

I am getting the following string in my java app from a client.

[["UIButton","Submit","15","30","80","80"],["UILabel","User name","15","75","80","80"],["UITextField","Jonathan","15","75","80","80"]]ˇ˛END

I am expecting to parse this and take out separately as 3 strings as like below:

"UIButton","Submit","15","30","80","80"
"UIButton","Submit","15","30","80","80"
"UIButton","Submit","15","30","80","80"

I have tried like below,

    // resultStr = [["UIButton","Submit","15","30","80","80"],["UILabel","User name","15","75","80","80"],["UITextField","Jonathan","15","75","80","80"]]ˇ˛END
    if ( resultStr.length()>0 && resultStr!=null ) {

        for (int i=0; i<resultStr.length(); i++) {
            int startInd = resultStr.indexOf('[');
            int endInd = resultStr.indexOf(']');
            if ( startInd>=0 && endInd>0 ) {
                String resStr =  resultStr.substring(startInd , endInd);
                if ( resStr!=null )
                    System.out.println("Applet resStr: " + resStr);
            }
            else
                System.out.println("Applet startindex, endindex failed");
        }
    }

But, this is not working, this is not rightly parsing like what I expected. Could someone advise how to parse the string separately as I expected ?

Answer 1

You can split this string using String.split() method:

String[] t = myString.substring(2, s.length()-7).split("\\],\\[");

So your code will look like this:

//resultStr = [["UIButton","Submit","15","30","80","80"],["UILabel","User name","15","75","80","80"],["UITextField","Jonathan","15","75","80","80"]]ˇ˛END
if ( resultStr.length()>7 && resultStr!=null ) {

    String[] resStrings = resultStr.substring(2, resultStr.length()-7).split("\\],\\[");    
    for (String resString: resStrings) {
        System.out.println("Applet resStr: " + resStr);
    }
}

As a result, you should have following output:

Applet resStr: "UIButton","Submit","15","30","80","80"
Applet resStr: "UILabel","User name","15","75","80","80"
Applet resStr: "UITextField","Jonathan","15","75","80","80"

Answer 2

Try with Pattern and Matcher using Lazy way and Lookaround

(?<=\[).*?(?=\])

online demo

OR possessive quantifier

(?<=\[)[^]]*+(?=\])

online demo

Sample code:

Matcher matcher = Pattern.compile("(?<=\\[).*?(?=\\])").matcher(strring);
while (matcher.find()) {
    System.out.println(matcher.group());
}