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Appending to a File

Question: How can I append to a file in Java?The file is ASCII. It exists. The program hasrights to the file. I just need to add to the endof the

How to calculate sqrt()

Question: How do you calculate sqrt()? Answer: Of course the best way to compute square roots is to useMath.sqrt(),but I assume your question is academic. I’m not sure of the

Passing Data Between Two Threads

Question: I am new to Java and am currently trying toassociate idioms and techniques from otherlanguages/environments with like capabilities inJava. Specifically, I am trying to determine howto perform inter-thread and

What is the Thread.interrupt()method’s purpose?

Question: What is the purpose of the Thread.interrupt()method? I expect that if I call the interrupt()method of a sleeping thread, anInterruptedException will be thrown. Here is aquick code sample showing

Using .net Classes to Log On to Mail Server

Question: How do I use the .net classes to log on to a mailserver and request, say, the number of new mailmessages? Or send a message?Just POP3/SMTP. An example would

Why Does Spawned Thread Work on PC and not Sun?

Question: This may be too vague, but:I spawn a thread (after a button click) which bringsup a new window. This works great on my PC runningNetscape 3.0 and Internet Explorer,

How to Prevent Simultaneous Access

Question: How do you lock a file in Java to prevent simultaneous multipleaccesses? Answer: If you’re concerned about simultaneous access by independent processes,you’ll have to rely on the host OS

Reading from URL into String

Question: What is the maximum size of a string array I can have in my applet?I am trying to store some stock prices in a string array after reading themfrom

Adding and Removing Columns from Tables

Question: How can I add and remove columns from a table at run time? Answer: While I’m an avid supporter of Delphi, one of the most annoying things about it

How do I set Paradox table passwords?

Question: How can I set Paradox table passwords in Delphi 2.0? Answer: Let Me Blow Off Some Steam About the BDEUnfortunately, setting passwords on Paradox tables cannot be done using

Accessing a C Library from Java Applet

Question: I want to be able use a Web frontend for a databaseapplication. I would like to use Java to process theuser input and C for accessing the database. Myquestion

What is an Interface?

Question: I have no experience with object-oriented languages, havingonly learned BASIC when I was a child. Most people say Java is easy,but in my case it’s not. I don’t understand

Too many TDBEdit components on a Form

Question: I am using Delphi 16 running under Win95.I have an application which requires use of more than 200 TDBEdit components. When designing the form I find that 178 appears

How can I properly use CreateProcess to instantiate a new process?

Question: Here is the code I’m using (the error is posted where it occurs):=================================TypePROCESS_INFORMATION = record hProcess: Longint; hThread: Longint; dwProcessID: Longint; dwThreadID: Longint;End;Procedure ExecCmd(cmdline: String);varprocc: PROCESS_INFORMATION;startup: TSTARTUPINFO;ret1: longint;ret2: longint;ret3:

Incremental Searches with a TListbox

Question: How can I create a form that has a list box that I can perform an incremental search on? Answer: There are a couple of ways to do this.

Creating Component Arrays

Question: In Visual Basic I can create component arrays, but I can’t seem to find a way to in Delphi. Does Delphi have this capability? Answer: Do You Really Need

Creating a roll-up form

Question: How can I create a form that will roll up; that is, a form that whenclicked will reduce its height to nothing but the title bar? Answer: I have

Can forms be manipulated at runtime?

Question: Can forms be manipulated at runtime? Answer: Typically, you want to have your programs visibleand have the ability to switch to them; however, there are times when youhave a

Is it possible to re-size arrays at runtime?

Question: Is it possible to re-size arrays at runtime? Answer: I came across an exampleof how to do one. The author is BenLicht, who has come up with a brilliant

Getting at a TRadioGroup’s Individual Buttons

Question: Is there a way to manipulate the appearance of the individual buttons in a TRadioGroup? Answer: This subject falls into the yeah, it’s something you could do, but should

Getting Data Out of an Applet

Question: I have an applet with dialog boxes, text fields and buttons.What can I do with the user input? How do I get it out of the applet?What else can

Process an XSL-FO Document

Sometimes you need to process an XSL-FO document that is the result of an XSLT transformation. Actually, the XSL-FO document doesn’t exist, it is just

Leveraging EJB Timers for J2EE Concurrency

oncurrency is a well-known technique for improving the performance of many J2EE applications. For example, Web 2.0 mashup applications must aggregate data from multiple sources.