Why does my Java code execute bash command incorrectly?

Why does my Java code execute bash command incorrectly?

I am trying to make my Java program interact with Linux bash but something
goes wrong. I have a simple executable prog that reads the one integer
from stdin and outputs its square. Executing
echo 5 | ./prog
from bash itself prints correct answer 25 in stdout but running
import java.io.*;
public class Main {
public static void main(String[] args) throws InterruptedException,
IOException {
Runtime run = Runtime.getRuntime();
Process proc = run.exec("echo 5 | ./prog");
proc.waitFor();
BufferedReader br = new BufferedReader(new
InputStreamReader(proc.getInputStream()));
while(br.ready())
System.out.println(br.readLine());
}
}
unexpectedly gives 5 | ./prog. What is the solution?