OR condition in java substring method

Question

While parsing the dynamic input string using the java substring method with start and end indexes, Can we use or condition in the end index of the substring method? Meaning end index could be either ')' or ',' for my use case.

Ex: my input string have below two formats

inputformat1 : Student(name: Joe, Batch ID: 23) is updated
inputformat2 : Student(name: John, ID:0, Batch ID: 2503, Result: pass) is updated

Now I am interested to get the "Batch ID" value every-time. I wanted to achieve this by substring method. Now I'm able to get the batch id value If I use any one of the indexes ie, ')' or ','

String batchId= input.substring(input.indexOf("Batch ID: ")+9,input.indexOf(")")); 

Can someone help me to the way to batch Id value basing on different end indexes?

Answer 1

You could use Math.min():

String batchId = input.substring(input.indexOf("Batch ID: ") + 9,
                     Math.min(tail_old.indexOf(")"), tail_old.indexOf(",")));

Answer 2

You can use regex with replaceFirst to solve your problem for example ;

List<String> strings = Arrays.asList("Student(name: Joe, Batch ID: 23) is updated",
        "Student(name: John, ID:0, Batch ID: 2503, Result: pass) is updated"
);
for (String string : strings) {
    System.out.println(
            string.replaceFirst(".*Batch ID:\\s+(\\d+).*", "$1")
    );
}

Outputs

23
2503

---

If you want multiple groups you can also use Patterns like so :

Pattern pattern = Pattern.compile("name:\\s+(.*?),.*?Batch ID:\\s+(\\d+)");
Matcher matcher;
for (String string : strings) {
    matcher = pattern.matcher(string);
    while (matcher.find()) {
        System.out.println(
                String.format("name : %s, age : %s", matcher.group(1), matcher.group(2))
        );
    }
}

Outputs

name : Joe, age : 23
name : John, age : 2503