Java FAQ « Asteriskese’s Opensource Weblog

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I just started with Java and found very strange that in simple operation like Memory Interceptor Library
Nokia pushing mobile development at Eclipse
Q: Can I pass a function as a parameter in Java? If so, how?
Q: How can I change the default icon on application window (java cup) to my own?
Q: How can I make my Java package name unique?
Q: How do I access to protected methods in third party package?
Q: I have made an applet in vJ++ which I have to sign.
Q: I need to communicate some data (string) from a Java Applet
Q: I would like to know how my Java program can catch when someone
Q: I’d like to know how to know which operating system java application
Q: I’m doing a small console java app, and want to know what the function
Q: Is there a collection object like the hashmap or hashtable that stores values
Q: Is there any way to accept password from a java application.
Q: Why do we need to use shift operator in Java? Can you give some examples?
Q: Why in the write method for the OutputStream class we have “int b”?
Question: Can anyone tell me why the Java Vector class is called a ”Vector”?
Question: I just started to work in big company… Before I worked with software
Question: I read that JDK 1.4 has new features: logging, xml, regular exp…
Question: I want to download Java 1.4. I looked on the page for compatability an
Question: I’m having problems with the JavaComm (javax.comm) serial / parallel A
Question: I’m just getting into Java and have a simple question: What is J2EE an
Question: I’m trying to write a script to package my class files into a jar file
Question: I’ve been using the java comm API to allow me to build a small java in
Question: If there was a ‘’setvalue()” method in Float class, it would have bee
Question: Is it new Java feature that my class has no constructor?
Question: Is there any way of getting the memory requirements of objects at run-
Question: Java has no sizeof() like C++… Why?
Question: JLabels: when I add ”too much” text I can’t see all of it.
Question: Please clarify my confusion about Java versions. I hear ”Java 2” but
Question: Quite often I see that programmers use full name of class in a program
Question: Some packages use capital letters in name and some low case? I read th
Question: Why do not distinguish methods based on their return value?
Question: Why do we need wrappers like Integer, Boolean for int, boolean in Java
Question: Why is thin client has name ”thin” in J2EE?
Solaris 10 & Red Hat Enterprise Linux 4.0 Dual boot : How to?
Sun president: PCs are so yesterday
The Value of the IBM Software Development Platform

Class.forName() loads a JDBC driver into the memory! Why do we need this?
CODAF 1.5 (stable) released with Compiere 2.5.2c support
Daffodil Open Sources Java Database One$DB at SourceForge
Daffodil Replicator v1.7 launched with Push-Pull Replication
Eclipse plugin eva/3 Application Builder for visual development and db managment
From 221 JDBC drivers find yours one that fits all requirements
I am reading my values from a db which is supposed to be a string, but sometime
I have a binary flat-file database that I need to access via JDBC. How do I crea
I have developed my program with MySQL and Java. It runs locally. Now I want to
IBM provides WebSphere application with JDBC/SQL

Biggest open diamond mine!
CodeInvaders Challenge – Java-based gaming with real-time programming
Friday’s not Java news again!
funny Cofe and Software
Funny dedication I found on the Net
High resolution free Java screensaver here!
Keep your eyes on …
Non profit remake of Star Wars!
Should we take out spammers… Literally?

FilePermission cannot Handle Symbolic Links? I was trying to change file permiss
I read that an object can be strongly, weakly or even phantom (!!!!) reachable..
Jakarta Commons IO 1.1 has been released

A strong cup of java can perk up your hair color
Have you heard about the object-oriented way to become wealthy?
Is text file binary?
My colleague, he is testing my code, got ”Headless Exception”. He jokes that i
Thief robs java shop, but pays for cup
Vodka, Programming and plugins
Why does not exist ”JavaNotFoundException”? When I deliver my Java program to

‘else’ Not Required
Abstract classes vs Interfaces: main differences
Advanced Installer for Java 1.7 Released
All String Handling in Java here!
alt.lang.jre: Get to know Jython
Analyst’s Soapbox: A nasty wake-up call for J2EE
Annotations in Tiger (J2SE 5.0)
Any idea how to lock a Session ID? Ho to prevent its usage again?
Are classes implementing Externalizable considered Serializable classes?
Array vs ArrayList vs LinkedList vs Vector: an excellent overview and examples
ArrayList vs. LinkedList
Autoboxing
Build distributed object management frameworks for J2EE apps
Can .Net And Java Be Friends?
Can I can force finalization using System.runFinalization()?
Can I convert my Delphi code to Java?
Can I convert Visual Basic code to Java?
Can I use try/catch block to control program flow? Will it affect program perfor
Can Java communicate with ActiveX objects?
Can the JavaHelp software run in a non-Java application, such as a C++ applicati
Can we just try without catch? Yes!
Can you tell me about ”100 Percent Pure Java Certification Program ”.
Cellular Automata and Music Using Java
Concurrency in JDK 5.0 Tutorial
Could you tell me about chain exceptions?
Data Management in J2EE Apps
Design Skinnable Java UIs with Native Performance
Develop Contact Center Telecom Applications
Do you know about ”Full Speed Debugging” and “HotSwap” Class File Replacem
Fail Early, Fail Often
Fixing the Java Memory Model, Part 2
For example I use some collection and method put() which has return type Object.
Free article on BigDecimal arithmetic
How can I check CLASSPATH variable on my OS?
How can I completely clean up my Windows XP from Microsoft JVM before I install
How can I convert any Java Object into byte array? And byte array to file object
How can I in Java convert this string 23AB to its hexadecimal representation 323
How can I install my Java program as a NT service?
How can I use the new error-reporting mechanism in JVM?
How can my application know how many CPUs work in a system?
How do I compare two dates and times, date between dates, time between times and
How do I increase the level of debugging information displayed in the Java Conso
How do I increase the level of debugging information displayed in the Java Conso
How is a multidimensional array stored in Java? Is it different from C?
How is JavaSpaces technology different from databases?
How to open, read, write, close file(s) in Java? Examples on move, rename and de
How to unsign signed bytes in Java - your guide is here
How unique serialVersionUID must be? Is not it enough with default one?
I am getting ”OutOfMemoryError”. How do I prevent such memory leaks?
I am getting ”StackOverflowError” error…
I am starting with Java now.. Could you point me some simple tool that can check
I do not like to write JavaDocs, I need some tool to help me…
I found that in Java API (when looked at v1.4.2) exist ”PrivilegedExceptionActi
I have a method that names something like this - public String doSmth()…
I have an application which can be run using 64 bit JNI libraries, or 32 bit lib
I have two String arrays: array A and array B. Now I want to get the elements of
I have written a small Java web server. I want to delete (replace) a class that
I heard many times from Java lectors: ”If you are interested how new feature wa
I just looked at Java Web Services Developer Pack (Java WSDP) and found that it
I know that exist many Java compilers, not only ”javac” from SUN
I know that Hashmap implementation is not synchronized. How can I synchronize it
I like JBuilder very much. Just one thing - mouse wheel is not supported…
I need to do a lot of technical computing in my Java programs. Could you advic
I need to program ”xyz” math function. Where can I find code examples?
I often do mistakes when write my JavaDoc comments. Do you know a tool to avoid
I often hear something like this ”daemon runs” or ”how to make my own daemon’
I read that in the Java (version 1.4.x) reflection implementation has been optim
I see that in Java a lot of Class loaders: bootstrap, extension, system, context
I show you now a class in Java which has no public constructor!
I tried to send Ctrl+Alt+Del key code to system from my class, but it does not w
I try to call the Runtime.exec() command by passing it an array of strings.
I use an old Java Tool from SUN. Today I read that SUN started End Of Life Proce
I use logging in my application… The problem is that I am opening the PrintWri
I want to create a logging system that handles the user, database, application s
I want to use COM component from Java. How can I get an access to the COM interf
I was considering an installation of java application on a new computer without
I was looking at java.util.Timer class and there is no possibility to cancel an
I was testing the new J2RE 1.4.2 for compatibility with our programs (written on
I would like to create a class that can execute jscripts. Does any one know if t
IBM releases free 2003 Software Evaluation Kit
IBM Security Providers: An Overview
If I turn off daylight saving during an installation of Windows XP then Java run
if Statement - Overview
If we write integer or double through Java in a file then the bit pattern for ea
In Ukraine first day of week is Monday but not Sunday
Interesting fact:
Interfaces in Java: Very easy to read overview
Intro to Java Tutorial
Introduction to Jena
Is it something new in J2SE 1.4.1?
Is it true that java.nio package name (I mean NIO part) means ”New Input/Output
Is there any way to keep an object from being collected by Garbage Collector?
It is not a big secret that file system in Java looks like UNIX file system. It
Iterator vs Enumeration?
Java 2 Platform and JAAS Authorization Architectures
Java Bytecode Engineering with BCEL
Java Calendar and Date: good to know facts and code examples
Java certification success, Part 1: SCJP
Java encapsulation gotchas
Java Message Service Tutorial
Java Message Service Tutorial
Java Shared Classes
Java theory and practice: State replication in the Web tier
Java Virtual Machine
Java vs .NET
Java: History of Java
Java: Strength
Java: Weaknesses
JDK 5.0: More Flexible, Scalable Locking
JMS Application Changes Under J2EE 1.4
Microsoft heed a key lesson learned or suffer the consequences
My application runs much slower with 1.3/1.4 when compared with the 1.2 Producti
My application uses just one class from big jar file. Does the entire jar file g
My Java application is for system with small memory. How to get the system’s fre
My program creates a huge number of objects dynamically and even more inside eac
NetBeans 4.1 Early Access Release Now Available
New Daylight Saving rules in USA and Java?
Object-Relation Mapping without the Container
Open Source J2EE 1.4 gets Sun green light
Orchestrating Grid Workloads w/ Tivoli
Our server (Solaris) accept a socket when got a request. Why can we only create
PHP To Challenge J2EE and .NET
Portal Apps Tutorial w/ Websphere and Struts
Portlets with FacesClient Components
Question: Do exist non SUN’s, freeware implementations of essential libraries fo
Question: How do I find out how long the JVM has been running?
Question: What is difference between add() and addElement() in Vector?
Question: What is difference between sets and lists?
Question: What is difference between sets and lists?
Question: what is fail-fast iterator in Java?
Quickly create Secure Portals with Java-based framework
Replacing Reflection with Code Generation
Serialize Java Object to file? How can I store and retrieve serialized objects t
News: softSCJD released
Sun revokes FreeBSD’s Java licence
Sun To Tighten NetBeans 4.1 and Java in 2005
Synchronized is implementation detail
Ternary operation or operator in Java: what is that?
The beta release of J2SE 1.5 is scheduled for late 2003. I have heard that there
The clear-Method in the java.util.Calendar-Class doesnt behave like I suggest.
The On Demand Operating Environment
Transforming JFrame Windows with IFrame
Unclogging Server Bottlenecks w/ Active Containers
Using Aspect-Oriented Programming to Maintain Legacy Java Apps
Webcast: Team Unifying Platform Ensures Interoperability
What are additional types of GC do exist in the J2SE platform, version 1.4.2?
What audio and video formats does the Java Media Framework support?
What can I do if some programming language has no methods to interact with Java
What does mean “Lists (like Java arrays) are zero based.”?
What does mean ”internalization” for me when I design my program and where sho
What does mean term ”peer” and what can I do with it if I use getPeer() in Com
What is date of Java birthday?
What is difference between Hashmap and Hashtable?
What is difference between RMI and Java Messaging? And between email and Java me
What is difference between the for(; and while(true)?
What is Java Space technology?
What is meant by persistence?
What is relation between JAXP and Xerces?
What is the maximum number of dimensions that a Java array can take?
What is young generation in GC(Garbage Collector)?
What type of garbage collection does a System.gc() do?
When do I need to use reflection?
When do I to choose an abstract class over an interface?
When does garbage collection performance matter to the user?
When I running Runtime.exec(…), I get a Process object. I want serialize it to
Where can I find sample code for J2EE guidelines, patterns, and code for end-to-
Where is MS Java Virtual Machine stored in IE? I would like to take them away…
Which Collection should I use in my Java program? Part 1. Hashtable vs hashmap?
Whizlabs Acquires INESystems, Maintains Lead in the J2EE Domain
Whizlabs Upgrades its SCMAD (J2ME Certification) Exam Simulator
Whizlabs Upgrades its SCWCD 1.4 (J2EE Certification) Exam Simulator
Why do I see the attribute in a derivative class? I can not access it anyway!
Why I can not compile it:
Why is Runtime.runFinalizersOnExit deprecated?
Why Java does not use default value which it should?
Why Java Hot Spot Compiler has the name - Hot Spot?
With 1.3.1 we got 4GB heaps on Solaris, why can’t I get this to work on Windows?
World’s first SCBCD certification exam simulator launched by Whizlabs

”Using Web Services Effectively” - the online tutorial
1.3, 1.4 –> 1.5 Migration
AJAX Interoperability Demo for WS-RT/WS-RP
An Overview of the Java WSDP 1.5
Concurrent Programming with J2SE 5.0
Demo Version of uCertify Exam Simulation PrepKit for Microsoft Exam 70-292 Relea
Exam Directory: New website for IT Certification Exam Information Launched
Five Reasons to Move to the J2SE 5 Platform
Getting Started with an Integrated Development Environment (IDE)
Getting Sun Java Certified
Gosling onto real time Java
If your system does take in external XML data this security tip is for you!
Is it possible to measure time in nanoseconds?
Java and PHP will work together!
Java is better than .NET! part I
Java is better than .NET! part II
Java preps dive into real-time role
Java Refreshable Objects
JMX for Managing Java Applications
New IBM Software PowerPack evaluation program for Java and .Net developers
New series of PHP lectures start!
No Cost developerWorks Live! Technical Briefings in 2004
Pass-Guaranteed.com Offers IT Career Enhancement Opportunities
Performance testing has shown that the finalize methods in the channel classes i
The Java Books page: the link errors are fixed now!
The Man Who Brewed Up Java
The Multi-Tasking Virtual Machine: Building a Highly Scalable JVM
Thread: run() vs start() method
Timing is Everything
uCertify announces Special Discounts on selected Exam Simulation PrepKits
uCertify Launches PrepKit for CompTIA Exam IK0-002 for i-Net+ Certification
uCertify Offers Exam PrepKit for Oracle 9i (1Z0-147) Exam
uCertify Offers Upto 70 % Limited Period Discount on Exam Simulation PrepKits.
uCertify.com announces the release date for new Exam Simulation on SCJP
Using JConsole to Monitor Applications
USING THE VARARGS LANGUAGE FEATURE
What is Java Isolates and why do we need it?
What is Model-View-Controller (MVC) architecture?
What is typical offshore model? Why offshore is so compelling?
Where can I find brief description for common set of design patterns which I can
Where could I buy gifts to my colleagues (t-shirts, glasses, caps, mugs and so o
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Find, sort, organize and enjoy the pictures on your computer in seconds.
Gif4J PRO 2.0 and Gif4J LIGHT 1.0 released
I am loading an image into my application from users and do not know in advance
In our application we try to send an image over socket connection in binary form
Java Desktop images
On some Windows 2000 machines our application (uses Java 2D) causes system crash
Question: I am trying to construct my GUI so that my images can act like JButton
Question: I have read that Java Advanced Imaging API uses native code…
Web icons in your web oriented application
Which Java library can convert psd format (Photoshop Image)? Is it free?

A new toolset for creating web-based user interfaces with Java
Applet and command line parameter?
Building Web Services w/ Eclipse Tutorial
Can one applet load another applet on runtime, and can these two applets talk?
Domino Custom JSP Tags Tutorial
Easily create new application simulators
Every time I access an Applet browser downloads all related classes.
HeapAnalyzer v 1.3.7 - fully supports Java Profile
How do I hide system properties that applets are allowed to read by default?
I am writing a chat applet and I would like to put icons in user messages. Is i
If I run my applet with the SUN VM I get exception: ”Either ”code” or ”objec
Is there a way to write information to cookies through an Applet?
Java: Applets
My applets are big and it takes much time to download (on browser) when a networ
Question: I have an applet. I have succesfully added the class to a JAR, but whe
Use a Java Applet to access remote Web services
What is the difference between applets loaded over the net and applets loaded vi

A Practical Introduction to Enterprise Java Beans
Delivering on the Promise of Wireless Applications
EJB programming restrictions
EJBs Tutorial: Access Heterogeneous Data w/ DB2
Oracle ADF JClient support in the new version of JDatePicker
Question: How many kinds of enterprise beans does Java has?
RAD Tutorial w/ JavaServer Faces and WS Portal
Tutorial: Simplifying EJB Component Development
XBeans?

Murach’s Java Servlets and JSP

I have found that ZipEntry() method behaves strange:
Reading Java’s API version 1.41 I noticed that many classes contain now valuable

How to make 32 byte UUID - Better Than java.RMI.server.UID
Java Array
Native From Java: Java code example
New Java book online starts now here…
Ready Java example: Embed JVM into native code.
Search JavaFAQ.nu site here
Tricky Java example: Display Icons without icons.

I defined an equals method, but Hashtable ignores it. Why?
I tried to forward a method to super, but it occasionally doesn’t work. Why?
Q: Can I get good advice from books on Java?
Q: Can I write sin(x) instead of Math.sin(x)?
Q: How big is an Object? Why is there no sizeof?
Q: I have a class with six instance variables, each of which could be initialize
Q: I have a complex expression inside a loop…
Q: I still miss global variables. What can I do instead?
Q: In what order is initialization code executed? What should I put where?
Q: Is null an Object?
Q: What about class initialization?
Q: What other operations are surprisingly slow?
Q: Why are there no global variables in Java?
Q: Why does my Properties object ignore the defaults when I do a get?
Q: Will I get killed by the overhead of object creation and GC?
Q:Inheritance seems error-prone. How can I guard against these errors?
Q:What are some alternatives to inheritance?
Q:When should I use constructors, and when should I use other methods?
Q:Within a method m in a class C, isn’t this.getClass() always C?
The code in a finally clause will never fail to execute, right?

Ergonomics in the 5.0 Java Virtual Machine
Eye on performance: Trash talk
How to improve performance?
I was using Java 1.4.x during of development of program. Our customers want to u
Java Performance Tuning w/ Fat Clients
Java: Ant
Java: CLASSPATH
Java: IDEs
Java: Packages - Importing
Java: Packages - Installing
Java: Style and Correctness Checkers
Java: Text Editors
Java: TextPad Editor
Make Tomcat page load faster
Q: How do I improve dramatically performance of my Java program?
ROXES Ant Tasks 1.0 Open Source released

Java Lesson 37: Menus and submenus
Java Lesson 38: The WindowListener interface and the WindowAdapter class
Java Lesson 39: An introduction to GridBagLayout
Java Lesson 40: An introduction to the Java Collections API
Java Lesson 41: Exception handling with try, catch, and finally blocks
Java Lesson 42: Claiming and throwing exceptions
Java Lesson 43: Multithreading, the Thread class, and the Runnable interface
Java Lesson 44: An introduction to I/O and the File and FileDialog classes
Java Lesson 45: Low-level and high-level stream classes
Java Lesson 46: Using the RandomAccessFile class
Java Lessons by Jon Huhtala: Update
The Java Lesson 10: for, while, and do-while statements
The Java Lesson 11: Using break and continue
The Java Lesson 12: Class methods and how they are called
The Java Lesson 13: Using the Math class
The Java Lesson 14: Creating and calling custom class methods
The Java Lesson 15: Overloading class methods
The Java Lesson 16: An introduction to objects and object references
The Java Lesson 17: The String class
The Java Lesson 18: The StringBuffer class
The Java Lesson 19: Initializing and processing arrays of primitives
The Java Lesson 1: What is Java?
The Java Lesson 20: Initializing and processing arrays of objects
The Java Lesson 23: Inheritance and overriding inherited methods
The Java Lesson 24: abstract classes and polymorphism
The Java Lesson 25: Interfaces, instanceof, and object conversion and casting
The Java Lesson 26: Introduction to graphical programming and the java.awt packa
The Java Lesson 27: The Component class
The Java Lesson 28: Containers and simple layout managers
The Java Lesson 29: The Color and Font classes