casemixer.java

程序练习中包括书中实例程序代码和练习中要用到的代码,是压缩文件

package examples.io;

import java.io.*; 
import java.util.Random; 

/** A class used to demonstrate file input and output
  */
public class CaseMixer {
   /** Method randomly sets case of characters in a
     * stream
     * @param args[0] The name of the input file 
     *   (defaults to standard in)
     * @param args[1] The name of the output file
     *   (defaults to standard out)
     * @throws IOException 
     *   if a error is detected opening or closing the
     *   files
     */
   public static void main( String[] args ) 
                           throws IOException {
      InputStream  istream;
      OutputStream ostream;
      if ( args.length >= 1 ) {
         File inputFile = new File( args[0] );
         istream = new FileInputStream( inputFile );
      } else {
         istream = System.in;
      }
      if ( args.length >= 2 ) {
         File outputFile = new File( args[1] );
         ostream = new FileOutputStream( outputFile );
      } else {
         ostream = System.out;
      }
      int c;
      Random mixer = new Random();
      try {
         while ( ( c = istream.read() ) != -1 ) {
            if ( mixer.nextFloat() < 0.5f ) {
               c = Character.toLowerCase( (char) c );
            } else {
               c = Character.toUpperCase( (char) c );
            }
            ostream.write( c );
         }
      } 
      catch( IOException iox ) {
         System.out.println( iox );
      }
      finally {
         istream.close();
         ostream.close();
      }
   }
}