Java/インスタンス

package sample;
import java.io.*;
public class SampleClass {
	public static void main(String[] args) throws IOException {
		Sample s1 = new Sample();
		Sample s2 = new Sample();
		Sample s3 = new Sample();
		System.out.println(Sample.getCount());
	}
}

class Sample {
	static int count = 0;
	static int getCount() {
		return count;
	}
	Sample(){
		count++;
	}
}