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Deprecated APIs

Question: How do I make a method deprecated? Answer: Deprecating a method or entire class is as simple as using the “@deprecated javadoc” tag in its documentation. For example: /**

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Using cin.good() to Check Inputted Numbers

Question: I’m trying to make a calculator program using switch statements for +,-,* and /. I know how to handle and divide by zero error. I also have to use

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Loading a New Window from a Frame.

Question: I have a frameset that consists of two frames. The top frame is a horizontal frame that displays a bulletin message in a banner if there is some sort

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Passing Value to an Online Form

Question: Is it possible to use JavaScript to create a custom page and pass all the values in the page to an online form such that I do not have

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Significance of const Return

Question: What is the significance of const return type from a function?Similar to: const int func1(); Answer: The const in this position guarantees that the caller of the function doesn’t

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Java Profiler

Question: Is there a profiler like JProbe which supports the Microsoft Virtual Machine? I already tried the -prof switch on the command line, but that doesn’t do everything I need.

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Reverse DNS

Question: If I can use the “InetAddress” class to acquire the IP address of a computer, is there a way to get the computer’s name from an IP address? Answer:

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Using errno in DLLs

C++ inherited from C the global variable errno which indicates the success status of a previous operations. An errno value of 0 indicates that the previous operation was successful whereas

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The vector::data() Member Function

In a previous tip, I discussed techniques for treating a vector object as an array. The two main forms of obtaining the internal array’s address are: &*v.begin(); // obtain address

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Uninitialized enum Variables

The value of an uninitialized automatic enum variable is indeterminate. Uninitialized global and static enum variables have a zero value by default. In this regard, enum variables are similar to

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The Modulus Operator

The operator % returns the remainder of dividing its two operands. For example: b=10%3; // b equals 1 Don’t confuse the modulus operator with the division operator: c=10/3; // division,

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Designing Custom Forms

Question: Is it possible to make changes to the text on the tabs? Answer: Sure, with the tab you want to change selected, just click Form > Rename This Page.

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Informix Backups Error Message

Question: We have Informix IDS 7.30 running under SCO 5.0.5. Backups by ontape fail with an error: “I/O read chunk 90, pagenum 2, pagecnt 1 –> errno = 9″But when

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Locking a Row

Question: How can I lock a row in a table from a stored procedure? Answer: You shouldn’t have to worry about locking. It’s done automatically by the engine when you

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Upgrading from AIX 4.2 to AIX 4.3

Question: We have plans to upgrade our AIX operating system to version 4.3. We are using Informix 7.31. Do we need any new Informix components (compilers etc.)? Answer: You probably

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SQLLog Wizard

The SQLLog Wizard is used to specify which tables are to be audited. The output of the wizard is a SQL script that that can be run in the Query

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Oracle OLE DB and MTS

Trying to figure out how to use the Oracle OLE DB Provider under MTS or COM+ and with Oracle’s OS Authentication? This article explains how these parts fit together and

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Image Changeovers

Question: I have seen plenty of text on script dealing with mouseovers, or ‘animation’ where an image can change every few seconds, but is there a way I can write

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Form Validation

Question: I need to perform a validation on five fields in a form. The logic is: If field1 length >0 then disallow form submission if field2,field3, field4, and field5 are

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Pop-up Window with Links to New Pages

Question: I want to set up a series of links in a pop-up window which, when clicked, will (a) close the popup window and (b) redirect the main page to

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Checking the State of a Stream

The iostream family of classes provides the following member functions and operators for checking the stream’s state: bool good() // returns true if no error flag is setbool eof() //

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Comma Separated Expressions

An expression may consist of one or more subexpressions. You can group several expressions in one statement and separate them with commas. For example: if(++x, –y, cin.good()) // three expressions

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The Semantics of const_iterator

A recent subscriber of one of the C++ newsgroups posted the following question:Why did the C++ standardization committee created a const_iterator instead of a const iterator? Or, at least, why

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Treating a Vector As an Array

In certain contexts, you have to treat a vector as an array of its elements. For example, suppose you have a function that takes int * as its argument. How

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The erase() Member Function of Associative Containers

The associative containers std::map, std::multimap, std::set, and std::multiset have the following three overloaded forms of the member function erase(): class map // simplified for brevity{public://..other members void erase(iterator position); //

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Object Class

Question: Every class in Java is supposed to extend the Object class by default. In case a user class extends some other class (e.g., if myclassextends yourclass), then is it

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Constructors and Member Variables

Question: After I have already declared an object, how can I call its constructor again to re-initialize its member variables? Answer: You can’t do that. C++ guarantees that for each

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Static Methods

Question: What is the purpose of static methods in Java? Answer: Static methods can be invoked without an instance of an object. They provide the ability to execute methods in

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Choosing a Column Depending on Procedure Argument

Question: Can I specify the column I want to select from as an argument to the procedure? Something like: create procedure show_product(language char(2), ID integer) returning char(255);define p_prod_name CHAR (255);select