import java.io.*; public class AllCapsDemo { public static void main(String[] arguments) { AllCaps cap = new AllCaps(arguments[0]); cap.convert(); } } class AllCaps { String sourceName; AllCaps(String sourceArg) { sourceName = sourceArg; } void convert() { try { // Create file objects File source = new File(sourceName); File temp = new File("cap" + sourceName + ".tmp"); // Create input stream FileReader fr = new FileReader(source); BufferedReader in = new BufferedReader(fr); // Create output stream FileWriter fw = new FileWriter(temp); BufferedWriter out = new BufferedWriter(fw); boolean eof = false; int inChar = 0; do { inChar = in.read(); if (inChar != -1) { char outChar = Character.toUpperCase( (char)inChar ); out.write(outChar); } else eof = true; } while (!eof); in.close(); out.close(); boolean deleted = source.delete(); if (deleted) temp.renameTo(source); } catch (IOException e) { System.out.println("Error -- " + e.toString()); } catch (SecurityException se) { System.out.println("Error -- " + se.toString()); } } }