Java外部C言語プログラムを呼び出し、標準入出力操作を行う

import java.lang.*;
class test3{
       public static void main(String []args) throws IOException{
                long a = System.currentTimeMillis();
                Process process = Runtime.getRuntime().exec("/home/xxx");// ， process
                PrintStream outputWriter = new PrintStream(new BufferedOutputStream(process.getOutputStream()));
                outputWriter.println("XXXX");
                outputWriter.flush();// ， 
                outputWriter.println("XXX");
                outputWriter.flush();
                outputWriter.println("XXX");
                outputWriter.flush();
                outputWriter.println("XXX");
                outputWriter.flush();
                outputWriter.println("XXX");
                outputWriter.flush();
                BufferedReader addResult = new BufferedReader(
                                                              new InputStreamReader(process.getInputStream())
                                                              );
                String line;
                while((line=addResult.readLine())!=null)
                {
                     System.out.println(line);
                 }
                long b = System.currentTimeMillis();
                System.out.println(b-a);
}
}