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Java Source | 2000-05-25 | 5.1 KB | 143 lines |
- //: NewIODemo.java
- //////////////////////////////////////////////////
- // Copyright (c) Bruce Eckel, 1998
- // Source code file from the book "Thinking in Java"
- // All rights reserved EXCEPT as allowed by the
- // following statements: You can freely use this file
- // for your own work (personal or commercial),
- // including modifications and distribution in
- // executable form only. Permission is granted to use
- // this file in classroom situations, including its
- // use in presentation materials, as long as the book
- // "Thinking in Java" is cited as the source.
- // Except in classroom situations, you cannot copy
- // and distribute this code; instead, the sole
- // distribution point is http://www.BruceEckel.com
- // (and official mirror sites) where it is
- // freely available. You cannot remove this
- // copyright and notice. You cannot distribute
- // modified versions of the source code in this
- // package. You cannot use this file in printed
- // media without the express permission of the
- // author. Bruce Eckel makes no representation about
- // the suitability of this software for any purpose.
- // It is provided "as is" without express or implied
- // warranty of any kind, including any implied
- // warranty of merchantability, fitness for a
- // particular purpose or non-infringement. The entire
- // risk as to the quality and performance of the
- // software is with you. Bruce Eckel and the
- // publisher shall not be liable for any damages
- // suffered by you or any third party as a result of
- // using or distributing software. In no event will
- // Bruce Eckel or the publisher be liable for any
- // lost revenue, profit, or data, or for direct,
- // indirect, special, consequential, incidental, or
- // punitive damages, however caused and regardless of
- // the theory of liability, arising out of the use of
- // or inability to use software, even if Bruce Eckel
- // and the publisher have been advised of the
- // possibility of such damages. Should the software
- // prove defective, you assume the cost of all
- // necessary servicing, repair, or correction. If you
- // think you've found an error, please email all
- // modified files with clearly commented changes to:
- // Bruce@EckelObjects.com. (Please use the same
- // address for non-code errors found in the book.)
- /////////////////////////////////////////////////
-
- // Java 1.1 IO typical usage
- import java.io.*;
-
- public class NewIODemo {
- public static void main(String[] args) {
- try {
- // 1. Reading input by lines:
- BufferedReader in =
- new BufferedReader(
- new FileReader(args[0]));
- String s, s2 = new String();
- while((s = in.readLine())!= null)
- s2 += s + "\n";
- in.close();
-
- // 1b. Reading standard input:
- BufferedReader stdin =
- new BufferedReader(
- new InputStreamReader(System.in));
- System.out.print("Enter a line:");
- System.out.println(stdin.readLine());
-
- // 2. Input from memory
- StringReader in2 = new StringReader(s2);
- int c;
- while((c = in2.read()) != -1)
- System.out.print((char)c);
-
- // 3. Formatted memory input
- try {
- DataInputStream in3 =
- new DataInputStream(
- // Oops: must use deprecated class:
- new StringBufferInputStream(s2));
- while(true)
- System.out.print((char)in3.readByte());
- } catch(EOFException e) {
- System.out.println("End of stream");
- }
-
- // 4. Line numbering & file output
- try {
- LineNumberReader li =
- new LineNumberReader(
- new StringReader(s2));
- BufferedReader in4 =
- new BufferedReader(li);
- PrintWriter out1 =
- new PrintWriter(
- new BufferedWriter(
- new FileWriter("IODemo.out")));
- while((s = in4.readLine()) != null )
- out1.println(
- "Line " + li.getLineNumber() + s);
- out1.close();
- } catch(EOFException e) {
- System.out.println("End of stream");
- }
-
- // 5. Storing & recovering data
- try {
- DataOutputStream out2 =
- new DataOutputStream(
- new BufferedOutputStream(
- new FileOutputStream("Data.txt")));
- out2.writeDouble(3.14159);
- out2.writeBytes("That was pi");
- out2.close();
- DataInputStream in5 =
- new DataInputStream(
- new BufferedInputStream(
- new FileInputStream("Data.txt")));
- BufferedReader in5br =
- new BufferedReader(
- new InputStreamReader(in5));
- // Must use DataInputStream for data:
- System.out.println(in5.readDouble());
- // Can now use the "proper" readLine():
- System.out.println(in5br.readLine());
- } catch(EOFException e) {
- System.out.println("End of stream");
- }
-
- // 6. Reading and writing random access
- // files is the same as before.
- // (not repeated here)
-
- } catch(FileNotFoundException e) {
- System.out.println(
- "File Not Found:" + args[1]);
- } catch(IOException e) {
- System.out.println("IO Exception");
- }
- }
- } ///:~