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Get the count of elements in HashMap in Java
Use the size() method to get the count of elements.
Let us first create a HashMap and add elements −
HashMap hm = new HashMap();
// Put elements to the map
hm.put("Maths", new Integer(98));
hm.put("Science", new Integer(90));
hm.put("English", new Integer(97));Now, get the size −
hm.size()
The following is an example to get the count of HashMap elements −
Example
import java.util.*;
public class Demo {
public static void main(String args[]) {
// Create a hash map
HashMap hm = new HashMap();
// Put elements to the map
hm.put("Maths", new Integer(98));
hm.put("Science", new Integer(90));
hm.put("English", new Integer(97));
hm.put("Physics", new Integer(91));
hm.put("Chemistry", new Integer(93));
// Get a set of the entries
Set set = hm.entrySet();
// Get an iterator
Iterator i = set.iterator();
// Display elements
while(i.hasNext()) {
Map.Entry me = (Map.Entry)i.next();
System.out.print(me.getKey() + ": ");
System.out.println(me.getValue());
}
System.out.println();
System.out.println("Count of elements = "+hm.size());
}
}Output
Maths: 98 English: 97 Chemistry: 93 Science: 90 Physics: 91 Size: 5
Updated on: 30-Jul-2019
10K+ Views
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