Question

I have a String that’s formatted like this:

"key1=value1;key2=value2;key3=value3"

for any number of key/value pairs.

I need to check that a certain key exists (let’s say it’s called “specialkey”). If it does, I want the value associated with it. If there are multiple “specialkey”s set, I only want the first one.

Right now, I’m looking for the index of “specialkey”. I take a substring starting at that index, then look for the index of the first = character. Then I look for the index of the first ; character. The substring between those two indices gives me the value associated with “specialkey”.

This is not an elegant solution, and it’s really bothering me. What’s an elegant way of finding the value that corresponds with “specialkey”?

Answer 1

Use String.split:

String[] kvPairs = "key1=value1;key2=value2;key3=value3".split(";");

This will give you an array kvPairs that contains these elements:

key1=value1
key2=value2
key3=value3

Iterate over these and split them, too:

for(String kvPair: kvPairs) {
   String[] kv = kvPair.split("=");
   String key = kv[0];
   String value = kv[1];

   // Now do with key whatever you want with key and value...
   if(key.equals("specialkey")) {
       // Do something with value if the key is "specialvalue"...
   }
}