Paying attention to exceptions in constructors : Constructor « Language Basics « Java

Java
1. 2D Graphics GUI
2. 3D
3. Advanced Graphics
4. Ant
5. Apache Common
6. Chart
7. Collections Data Structure
8. Database SQL JDBC
9. Design Pattern
10. Development Class
11. Email
12. Event
13. File Input Output
14. Game
15. Hibernate
16. J2EE
17. J2ME
18. JDK 6
19. JSP
20. JSTL
21. Language Basics
22. Network Protocol
23. PDF RTF
24. Regular Expressions
25. Security
26. Servlets
27. Spring
28. Swing Components
29. Swing JFC
30. SWT JFace Eclipse
31. Threads
32. Tiny Application
33. Velocity
34. Web Services SOA
35. XML
Microsoft Office Word 2007 Tutorial
Java Tutorial
Java Source Code / Java Documentation
Java Open Source
Jar File Download
Java Articles
Java Products
Java by API
C# / C Sharp
C# / CSharp Tutorial
ASP.Net
JavaScript DHTML
JavaScript Tutorial
JavaScript Reference
HTML / CSS
HTML CSS Reference
C / ANSI-C
C Tutorial
C++
C++ Tutorial
PHP
Python
SQL Server / T-SQL
Oracle PL / SQL
Oracle PL/SQL Tutorial
PostgreSQL
SQL / MySQL
MySQL Tutorial
VB.Net
VB.Net Tutorial
Java » Language Basics » ConstructorScreenshots 
Paying attention to exceptions in constructors
Paying attention to exceptions in constructors

// : c09:Cleanup.java
// Paying attention to exceptions in constructors.
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// www.BruceEckel.com. See copyright notice in CopyRight.txt.

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

class InputFile {
  private BufferedReader in;

  public InputFile(String fnamethrows Exception {
    try {
      in = new BufferedReader(new FileReader(fname));
      // Other code that might throw exceptions
    catch (FileNotFoundException e) {
      System.err.println("Could not open " + fname);
      // Wasn't open, so don't close it
      throw e;
    catch (Exception e) {
      // All other exceptions must close it
      try {
        in.close();
      catch (IOException e2) {
        System.err.println("in.close() unsuccessful");
      }
      throw e; // Rethrow
    finally {
      // Don't close it here!!!
    }
  }

  public String getLine() {
    String s;
    try {
      s = in.readLine();
    catch (IOException e) {
      throw new RuntimeException("readLine() failed");
    }
    return s;
  }

  public void dispose() {
    try {
      in.close();
      System.out.println("dispose() successful");
    catch (IOException e2) {
      throw new RuntimeException("in.close() failed");
    }
  }
}

public class Cleanup {

  public static void main(String[] args) {
    try {
      InputFile in = new InputFile("Cleanup.java");
      String s;
      int i = 1;
      while ((s = in.getLine()) != null)
        // Perform line-by-line processing here...
      in.dispose();
    catch (Exception e) {
      System.err.println("Caught Exception in main");
      e.printStackTrace();
    }
  }
///:~



           
       
Related examples in the same category
1. Order of constructor callsOrder of constructor calls
2. Constructors and polymorphism don't produce what you might expectConstructors and polymorphism don't produce what you might expect
3. Constructor initialization with compositionConstructor initialization with composition
4. Demonstration of a simple constructorDemonstration of a simple constructor
5. Constructors can have argumentsConstructors can have arguments
6. Show Constructors conflicting
7. Show that if your class has no constructors, your superclass constructors still get calledShow that if your class has no constructors, your superclass constructors still get called
8. Constructor calls during inheritanceConstructor calls during inheritance
w__w_w.j__a__v__a___2___s___.___c_o__m___ | Contact Us
Copyright 2003 - 08 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.