CS670K - Special Topics - Java for C++ Programmers - Fall 1997

A program to copy a byte at a time from the input stream to the output print stream:

import java.io.*;

class copy1
{
	public static void main(String s[]) throws IOException
	{
	int c;
	for  (c= System.in.read();  c>=0; c= System.in.read())	System.out.write(c);
	}
}

A program to copy bytes, a line at a time from the input stream to the output print stream:

import java.io.*;

class copy2
{
	final static int MAX= 80;

	public static void main(String t[]) throws IOException
	{
		byte b[]= new byte[MAX];
		int length;
		while((length= System.in.read(b)) > 0)
			System.out.write(b, 0, length);
	}
}

A program which reads floating point values and calculates the sum of values averaged over the number of input lines:

import java.io.*;
import java.util.StringTokenizer;

class average
{
	final static int MAX= 80;

	public static void main(String arg[]) throws IOException
	{
		byte b[]= new byte[MAX];
		int length;
		float sum= 0;
  		int   line= 0;

		while((length= System.in.read(b)) > 0)
		{
			StringTokenizer str= new StringTokenizer(new String(b,0));

			while  (str.hasMoreTokens())
			{
				String s= str.nextToken();
				boolean valid= true;
				float f= 0;

				try                 {f= (new Float(s)).floatValue();}
				catch(Exception e)  {valid= false;                  }

				if  (valid)  sum += f;
			}
			if  (b[length-1] == '\n')  ++line;
		}

		System.out.println( "Average per line= " + sum/line );
		System.in.read(b);  // Pause to view result in J++
	}
}

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