| |
| |
|
softwarecatch.com
|
|
|
|
Assertion in Java
Assertion facility is added in J2SE 1.4. In order to support this facility J2SE 1.4 added the keyword assert to the language, and AssertionError class. An assertion checks a boolean-typed expression that must be true during program runtime execution. The assertion facility can be enabled or disable at runtime. Declaring Assertion Assertion statements have two forms as given below assert expression; assert expression1 : expression2; The first form is simple form of assertion, while second form takes another expression. In both of the form boolean expression represents condition that must be evaluate to true runtime. If the condition evaluates to false and assertions are enabled, AssertionError will be thrown at runtime. Some examples that use simple assertion form are as follows. assert value > 5 ; assert accontBalance > 0; assert isStatusEnabled(); The expression that has to be asserted runtime must be boolean value. In third example isStatusEnabled() must return boolean value. If condition evaluates to true, execution continues normally, otherwise the AssertionError is thrown. Following program uses simple form of assertion //AssertionDemo.java Class AssertionDemo{ Public static void main(String args[]){ System.out.println( withdrawMoney(1000,500) ); System.out.println( withdrawMoney(1000,2000) ); } public double withdrawMoney(double balance , double amount){ assert balance >= amount; return balance - amount; } } In above given example, main method calls withdrawMoney method with balance and amount as arguments. The withdrawMoney method has a assert statement that checks whether the balance is grater than or equal to amount to be withdrawn. In first call the method will execute without any exception, but in second call it AssertionError is thrown if the assertion is enabled at runtime. Enable/Disable Assertions By default assertion are not enabled, but compiler complains if assert is used as an identifier or label. The following command will compile AssertionDemo with assertion enabled. javac -source 1.4 AssertionDemo.java The resulting AssertionDemo class file will contain assertion code. By default assertion are disabled in Java runtime environment. The argument -eanbleassertion or -ea will enables assertion, while -disableassertion or -da will disable assertions at runtime. The following command will run AssertionDemo with assertion enabled. Java -ea AssertionDemo or Java -enableassertion AssertionDemo Second form of Assertion The second form of assertion takes another expression as an argument. The syntax is, assert expression1 : expression2; where expression1 is the condition and must evaluate to true at runtime. This statement is equivalent to assert expression1 : throw new AssertionError(expression2); Note: AssertionError is unchecked exception, because it is inherited from Error class. Here, expression2 must evaluate to some value. By default AssertionError doesn't provide useful message so this form can be helpful to display some informative message to the user. Rahim Vindhani
MORE RESOURCES:
Google News |
|
|
|
RELATED ARTICLES
Microsoft Great Plains Upgrade - Things to Consider and FAQ If you have Microsoft Great Plains and support it for your company then you need to know some technical details about Great Plains version upgrade and what is going on behind the scenes, which options do you have in case of Dexterity, VBA, SQL customization, additional complexity comes with migration from ctree/Pervasive to MS SQL/MSDE.What is upgrade in the language of technology? Upgrade has server and client sides. The Religion And Philosophy Of Small Internet Business I have always had a tendency to focus on the positive. We, all of us, know the negative details in society and governments. Builders Beware Which Type of Shop Can Rely On A Home Built System?Not all shops are at a disadvantage when it comes to building their own system. To determine which avenue a shop should take, owners must know what type of shops benefit from a self built solution and what type is better off purchasing one. Microsoft Great Plains Reporting - Overview for Developer Looks like Microsoft Great Plains becomes more and more popular, partly because of Microsoft muscles behind it. Now it is targeted to the whole spectrum of horizontal and vertical market clientele. The Truth: Netzero 3G We've all seen the ads on TV for Netzero 3G. You know the ones, "speeds so fast you sworn it was broadband" Well if your using it, you may not think it really is. Does your Company have Documentum? Are you lost in the mess of documents that get passed around your company, never knowing what the latest version is and which one you should work on without worrying if someone else has already made the same editions that you are making? Perhaps you have heard of collaboration software solutions such as Documentum to help your company manage its documents that are passed around. Documentum is a very good solution to this problem but is it the only one? In this article you will be presented with some basic information about the differences in collaboration software from Documentum and NextPage. Microsoft Great Plains: If You are Orphan Client - What to Do and FAQ Microsoft Business Solutions Great Plains, former Great Plains Software eEnterprise, Dynamics and Dynamics C/S+ is very popular ERP and since 1994 has been successfully implemented for mid-size and mid-size to large companies in the USA, Canada, UK, Australia, New Zealand, South Africa and Middle East. During the economic recession time 2001-2004 the majority of businesses cut to virtually zero their IT/computer support expenses and stayed with hardware and software. You Can Write Microsoft Office Program in About 60 Minutes Microsoft Office program is a programming tool called Visual Basic for Applications (VBA) that comes with Microsoft Excel, Word, Outlook, Power Point, and Publisher. VBA can make your repeating jobs automatic. Lowering The Risks In Developing Do-It-Yourself Software Projects Mike Dunville* had a decision to make. As the new operations manager for Alpha Staffing, he wanted to make a difference at the dynamic staffing firm. Great Plains Customization Upgrade- Overview For CIO/IT Director Around the same time Microsoft made its move with .Net introduction and tried to gain portion of cheaper databases market: Pervasive SQL/Btrieve, Ctree/Faircom - and launched free MSDE database program. Software Automation Helps Increase your Bottom Line When you own a small business, time is money. And every time a task that should be automated is handled manually, it wastes your time and your business loses money. Microsoft Business Solutions VAR/Partner Selection - Overview for IT Director/Manager/Controller Microsoft Great Plains and Microsoft CRM become more and more popular, partly because of Microsoft muscles behind them. Now Great Plains is targeted to the whole spectrum of horizontal and vertical market clientele. Microsoft CRM Programming Secrets - Tips For Developers This article is for advanced Microsoft CRM SDK C# developers. It describes the technique of direct SQL programming, when SDK doesn't have the functionality to do the job. MSN Messenger Is A Sweet Way To Communicate MSN messenger is a pretty cool invention. I mean I'm not really into serious discussions on the email, answers to questions can often take a few days to arrive because people are so busy these days. Unofficial Windows 98 SE Service Pack 2.0 RC2 Microsoft has never released a service pack for Windows98 SE, but I made a Service Pack for Windows98 SE users.It contains all Windows98 SE updates from Windows Update site and more. Guide to Software Marketing Intro This concise article will tell you in plain English how you can promote your software easily and effectively.Submit your software I recommend submitting your software to upload. Beware of Spyware One day, you suddenly realize that your computer started to work noticeably slower than it used to. You decide to run de-fragmentation of your hard drive and add more virtual memory to the system. The Dirt on Screensavers Remember back in the days where screensavers were the coolest thing at the office? You could stare at your co-worker's "fish in the ocean" screensaver at the cubicle next door for hours and actually have a full afternoon of conversation about that one screensaver.Well, screensavers are still "in", but not as "in" as they used to be. Groupware Finds Home in American Business: Collaboration Tool Analysis What is Groupware?Have you ever had to manage document collaboration in a hurry? No need to be ashamed if you said "yes." Virtually every American business has experienced moments of ad hoc team collaboration. Imagine if Everyone Working In Your Office Was In Synch? Microsoft-Outlook is a pretty amazing program. So much more than simply an e-mail client, it provides a task list, a powerful calendar with recurring scheduling capabilities, wonderful electronic sticky notes, mail-merge capability with MS-Word support and so much more.
|
|
Powered By: Free Work At Home Business Opportunity! |
| © 2006 |