Question

I have written a code to check if a string has the key in a give Map and replace the key with the value in the string.
Below is the code

            String s ="VamshiKrishnaA";
    Map<String,String> h = new HashMap<String,String>();
    h.put("Vamshi", "89");
    h.put("VamshiKrishnaA","dataDir");
    h.put("VamshiKrishna","dataDira");

    h.put("VamshiK", "krihsn");

    String key="";

    Iterator<String> i =h.keySet().iterator();
    while(i.hasNext()){
        key=i.next();
        if(s.contains(key)){
            s=s.replace(key, h.get(key));
        }
    }
    System.out.println(s);

When i run the above code, i got the output as dataDiraA but i need output to be dataDir.

I dont have control over the order of the key and values it is autogenerated.

Need any help in this regard

Answer 1

You need to track the length of the currently matched key, and only use the one which is the longest:

String matchedKey = null;

while (i.hasNext()) {
    key = i.next();
    if (s.contains(key) && (matchedKey == null || matchedKey.length() < key.length())) {
        matchedKey = key;
    }
}
if (matchedKey != null) {
    s = s.replace(matchedKey, h.get(matchedKey));
}