import library.io.*;
import java.kernel.*;

public class SKMemoryTest{
    static final int MAX_FILE_NUM = 1019;
    static Runtime rt = Runtime.getRuntime();
    static int filenum = 0;
    //    static long free1, free2;
    static long start, end;
    static RandomAccessFile farray[];
    static int round = 1;
    static long open_overhead = 0;
    //static long mem_overhead = 0;

    public static void main(String[] args){
	President.setCurrentCell(new SKMemoryTest());
	President.setSecurityManager(true);
	if(args.length > 0)
	    filenum = Integer.parseInt(args[0]); 
	System.out.println("input filenum = " + filenum);
	if (filenum <= 0) filenum = MAX_FILE_NUM;
	File f = new File("MemoryTest.dat");
	for(int j = 0 ; j < round; j++){
	    long start, end;
	    farray= new RandomAccessFile[filenum];
	    //  free1  = rt.freeMemory();
	    start = System.currentTimeMillis();
	    test(f);
	    end = System.currentTimeMillis();
	    //free2 = rt.freeMemory();
		    
	    open_overhead +=(end-start);
	    //mem_overhead +=(free1-free2);
	}
	System.out.println("File number     :" + filenum);
	System.out.println("Time overhead   :" + open_overhead/round + " millseconds");
	//	System.out.println("Memory overhead :" + mem_overhead/round + "bytes");
        clear();
        }


    static void test(File f){
	int i = 0;
	while(i < filenum){
	    try{
		farray[i] = new RandomAccessFile(f, "rw");
	    }catch(Exception e){e.printStackTrace();}
	    i++;
	}
    }

    static void clear(){
	int i = 0;
	while(i < farray.length){
	    try{
		((RandomAccessFile)farray[i]).close();
	    }catch(Exception e){e.printStackTrace();}
	    farray[i] = null;
	    i++;
	}
	farray = null;
    }
    
}