Prime Checker

JavaHackerrank/Prime Checker.java

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+import java.io.*;
+import java.util.*;
+import java.text.*;
+import java.math.*;
+import java.util.regex.*;
+import java.lang.reflect.*;
+import static java.lang.System.in;
+class Prime {
+    void checkPrime(int... numbers) {
+        for (int num : numbers) {
+            if (isPrime(num)) {
+                System.out.print(num + " ");
+            }
+        }
+        System.out.println();
+    }
+
+    boolean isPrime(int n) {
+        if (n < 2) {
+            return false;
+        } else if (n == 2) {     // account for even numbers now, so that we can do i+=2 in loop below
+            return true;
+        } else if (n % 2 == 0) { // account for even numbers now, so that we can do i+=2 in loop below
+            return false;
+        }
+        int sqrt = (int) Math.sqrt(n);
+        for (int i = 3; i <= sqrt; i += 2) { // skips even numbers for faster results
+            if (n % i == 0) {
+                return false;
+            }
+        }
+        return true;
+    }
+}
+public class Solution {
+
+	public static void main(String[] args) {
+		try{
+		BufferedReader br=new BufferedReader(new InputStreamReader(in));
+		int n1=Integer.parseInt(br.readLine());
+		int n2=Integer.parseInt(br.readLine());
+		int n3=Integer.parseInt(br.readLine());
+		int n4=Integer.parseInt(br.readLine());
+		int n5=Integer.parseInt(br.readLine());
+		Prime ob=new Prime();
+		ob.checkPrime(n1);
+		ob.checkPrime(n1,n2);
+		ob.checkPrime(n1,n2,n3);
+		ob.checkPrime(n1,n2,n3,n4,n5);	
+		Method[] methods=Prime.class.getDeclaredMethods();
+		Set<String> set=new HashSet<>();
+		boolean overload=false;
+		for(int i=0;i<methods.length;i++)
+		{
+			if(set.contains(methods[i].getName()))
+			{
+				overload=true;
+				break;
+			}
+			set.add(methods[i].getName());
+
+		}
+		if(overload)
+		{
+			throw new Exception("Overloading not allowed");
+		}
+		}
+		catch(Exception e)
+		{
+			System.out.println(e);
+		}
+	}
+
+}