Question

How to check if a key exists in TreeMap in Java

Answer 1

package javaapplication1;

import java.util.TreeMap;

public class JavaApplication1 {

    public static void main(String[] args) {

        TreeMap treeMap = new TreeMap();

        treeMap.put("1", "Java");
        treeMap.put("2", "C");
        treeMap.put("3", "C++");
        treeMap.put("4", "C#");
        treeMap.put("5", "PHP");

        boolean b = treeMap.containsKey("3");
        System.out.println(b);
    }
}
 
/*

run:

true

*/

 

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