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Question: I have a very large table that contains thousands of rows. I want to let a user insert new rows into it on a particular form without having to
Question: on a form based on the selection. I tried this two ways: 1) Using the validate method. This worked when the value was changed but not when scrolling through
Question: I’m using an evaluation copy of OPO for the Mac. After I create a table, I go into the table structure window to try and change the table structure
Question: I am 14 years old and a new Java programmer. I would like to know the difference betweenan instance and an object.I am learning Java from the book Teach
Question: I have two applets running on the same page, one in each of two frames. I want them to communicate, but when I do a getAppletContext.getApplet() call, the second
Question: I mainly do database applications and I am currently working on a project that will become very big. I have been trying to find any references to comparisons between
Question: When I attempt to preview a report in OPO under Windows95, I get an error: WFW-03049: Internal buffer too small for printer port name Is this an OPO or
Question: I’m building some process control software and I need to addlabels, such as Upper Control Limit (UCL), into my chart. Answer: The graph control was added to PowerBuilder in
Question: How can code in one frame construct an object whose constructor is declared in another frame? For example, new parent.SomeObject(); does not seem to work. Why? Answer: Good question!
Question: I know I can’t read files from a local machine through my browser, but I can’t seem to read a file off my originating server either. There’s a way
Question: I have this declaration in init: pushButton1 = new Button(“0”). In the action class I try to increase the value from 0 through 9 every time I click the
Question: Is it possible to pass a method to another class,so that method can be called by that class at a later date?For example, in C you can pass an
Question: What is the difference between the types’float’ and ‘Float’ in Java? Answer: A variable of type float contains an IEEE single precision number,while a variable of type Float contains
Question: I would like to create a very simple applet that pings anIP address and returns a message stating whether that IP is alive. Icouldn’t find any straightforward answers to
Question: I’ve been to sites where dialog boxes appear. How can I create one?I also want to ask users for their names, and then to be able to tell how
Question: How do I include reserved characters suchas double-quote in the strings passed to an applet from a PARAM tag?Standard SGML entities don’t work; the UNIX backslash method doesn’t work.
window.close() method always work?
Question: Why doesn’t the window.close() method always work? Answer: In JavaScript 2.0, the window.close() method could be used to close any open browser window. People being the malicious animals that
Question: Where can I find algorithms and data structures, techniques and programs that will better show me how they can be implemented using ANSI C? Other areas include Hashing, Heaps,
Question: How do I create a TextField that handles a password?What are the KEY_ACTION events associated with it? Answer: The setEchoCharacter() method within the TextField class allows youto do precisely
Question: I would like to be able to browse my server and havean applet/program that would mimic the functions of,say, the control panel on a Macintosh.Would I needto write a
Question: Constant downloading and fear of accumulating masses of useless files is turning me off on Internet. My concept of Java is that exe files, etc., will be on the
Question: Is it possible to have Java talk to a localserial port on a machine, for example,COM1 or COM2 on a PC?Is there a way to do this without nativemethods,
Question: How do I refer to/utilize the getImage(…) method whenusing it in an application, as I can only get it to work for an applet? Answer: To display images in
Question: Is it possible to add a menu bar to an applet without usingFrame as the container?Also, is it possible to show a Frame without a new window poppingup?I am
Question: How can I respond to a mousedown event in a TextField? Answer: From the Java 1.0.2 API specs:“In Java 1.0, the AWT does not send mouse or focus events
Question: How can I use JavaScript functions defined in an external file? Answer: When JavaScript and the tags, you can save it in a separate file and add a src
Question: Can JavaScript be used to access the client’s printer? Answer: No. JavaScript was designed so that malicious JavaScript programmers would have very little power to make their victims miserable.
Question: I am unable to run an applet and use a drop-downbox on the same page when using Netscape. The page hasmassive flickering and the applet will sometimes run. Theapplet
Question: I know that in order to pass something byreference, you pass an already-created objectand let the subroutine modify the contents ofthat object. Unfortunately, the Integer, String,etc. objects don’t allow
Question: Is there a way to determine the number ofinstantiated objects of a certain class? Answer: Unfortunately, there are no methods of class Object orClass thattrack the number of extant