CODEWITHSUNDEEP
javalist
user2441441
user2441441

Reputation: 1387

print <key,value> of List that have a specific value

I have defined a list as:

  List<Entry<String, Integer>> list

It has the count of the string. I want to iterate over the list and print all strings/keys that have a count of 1.

This is what I tried:

for (int i=0;i<list.size();i++) {
    if(list.get(i) == 1){
        System.out.println(list(i));
    }
}

I get "Incompatible operand types Map.Entry and int"

Upvotes: 1

Views: 690

Answers (4)

Prabhakaran Ramaswamy
Prabhakaran Ramaswamy

Reputation: 26104

You have list of Map.Entry objects. You can iterate the list using below code.

for (Map.Entry<String, Integer> entry:list) {
    if(entry.getValue() == 1){
        System.out.println("key":+entry.getKey());
        System.out.println("value":+entry.getValue());
    }
}

Upvotes: 1

Sergey Kalinichenko
Sergey Kalinichenko

Reputation: 726849

You can do it easier with a "foreach" kind of the for loop, like this:

for (Map.Entry<String,Integer> entry : list) {
    if (entry.getValue() == 1) {
        System.out.println(entry);
    }
}

The idea is to skip the index altogether, and use Java's built-in iterating capabilities to shorten your code.

Upvotes: 6

Sotirios Delimanolis
Sotirios Delimanolis

Reputation: 280122

"Incompatible operand types Map.Entry and int"

That's because you are comparing a Map.Entry reference with an int.

You need to get each element of the List as an Entry and use its value property in your if condition comparison

for (int i=0;i<list.size();i++) {   

    Entry<String, Integer> e = list.get(i);

    if(e.getValue() == 1){
        System.out.println(e);
    }
}

I don't know why you have a List<Entry>, but there is probably a better way to iterate over Entry elements, ie. an Iterator.

Upvotes: 1

rgettman
rgettman

Reputation: 178303

If you must use List<Entry<String, Integer>>...

You retrieved your Entry<String, Integer> from the list, but you're comparing it with 1. You need to go one step further and retrieve the Integer from the Entry, presumably with getValue().

if(list.get(i).getValue() == 1){

Additionally, list(i) won't compile. You may want to declare a new variable for holding the result of list.get(i) so you won't have to call get twice on the same entry.

Upvotes: 2

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