A try block must have a corresponding catch or atleast a finally block. The purpose of a try block is to identify areas in the code where exceptions may be generated and handle them. So, if you dont have a catch block, the whole purpose of using the try block is defeated
A "final catch" or a "try catch" statement is an exception (error) handling statement that will try to run the code between the final/try and "catch". If an error has been encountered, then the computer will proceed to the catch portion of the statement to prevent the program from terminating on error.
In Java, if there is a run-time error then it allows the user to explicitly handle it by catching it in the catch block. If there is any error in the try block of code, automatically the flow control will be transferred to the catch block. Here Exception e indicates any exception. The same is true in both Visual Basic and C#. This is seen in the try {} catch (Exception e) {} blocks. Which then function as the previous poster said. == == == ==
A non-caught exception is propagated out of the local catch block into the next catch block, daisy chaining to the outermost catch block in the run-time library, where it will be handled by abending the program.
If you have an exception you should fix mistake in your try block. If you want to run some code even after exception was thrown you can use full form of try block:try{...}catch (...){...}finally{...}Where the statement finally is what you need. Make sure that the code you run within this statement is not able to trow exceptions.
Exception: It is a Runtime error Exception handling if done by1)Error detection2)Error Reporting3)Error HandlingIs implemented by following keywords try,catch,finally,throws,throwstry{}If exception occurs in try block the appropriate exception handlers that is associated with the try block handles the exception.try block must have atleast one catch block follows it immediatelycatch(Exception e) {}The catch statement take object of an exception as parameter .If an exception is thrown the statements in the catch block is executed.There should not be any statement between try and catch block.we can have more then one catch block for one try block.finally{}It not mandatory to have a finally blockSometime it is necessary to process certain statement whether exception occur or notfinally block exceutes even if exception occurs or notOther then try catch block we directly handle a exception by using throws keyword throw keyword allows us to create user define exception
You need to have enough strengths and you have to run faster.
Runtime Error Cannot be Rectified but Runtime Exception can.
Many different programs can cause your computer to act strangely, freeze, reboot, or act on its own, including: - Viruses - Malware - Trojans - Buggy or poorly-written programs (esp. those without exception handling) - Programs run on an unsupported version of an operating system
Exception Handling is probably the most useful of the topics that are covered under the SCJP exam. Exception handling helps us catch or identify abnormal scenarios in our code and handle them appropriately instead of throwing up a random error on the front-end (User Interface) of the application.Exception handling allows developers to detect errors easily without writing special code to test return values. Even better, it lets us keep exception-handling code cleanly separated from the exception-generating code. It also lets us use the same exception-handling code to deal with a range of possible exceptions.Catching Exceptions - Using try and catchThe term "exception" means "exceptional condition" and is an occurrence that alters the normal program flow. A bunch of things can lead to exceptions, including hardware failures, resource exhaustion, and good old bugs. When an exceptional event occurs in Java, an exception is said to be "thrown." The code that's responsible for doing something about the exception is called an "exception handler," and it "catches and handles" the thrown exception.Exception handling works by transferring the execution of a program to an appropriate exception handler when an exception occurs. For ex: Your website displays the users bank account details. Suddenly if the bank database is down, imaging how the user would feel if an abrupt error page with numerous lines of java exception messages spewed all over the screen? First of all, it would be embarrassing and second of all, the user will get annoyed. Instead, if your code catches this database down scenario and displays a graceful message on screen saying "We are currently experiencing some difficulties in our system. Kindly try after some time. Thank you" it would be much better isn't it? That is exactly why we have or rather why we need Exception Handling.To do this, we use the try and catch keywords. The try is used to define a block of code in which exceptions may occur. This block of code is called a guarded region (which really means "risky code goes here"). One or more catch clauses match a specific exception to a block of code that handles it. Here's how it looks in pseudocode:1. try {2. // This is the "guarded region"3. // All your bank database access code goes here4. // And any other code that might process that data5. // We may have many code lines here6. }7. catch(DatabaseDownException) {8. // Put code here that handles this exception.9. // Put the graceful error message here10. // This is the last line of the exception handler.11. }12. catch(SomeOtherException) {13. // Put code here that handles this exception14. }15.16. // Some other unguarded code continues from hereIn this pseudocode example, lines 2 through 5 constitute the guarded region that is governed by the try clause. Line 7 is an exception handler for an exception of type DatabaseDownException. Line 12 is an exception handler for an exception of type SomeOtherException. Notice that the catch blocks immediately follow the try block. This is a requirement; if you have one or more catch blocks, they must immediately follow the try block. Additionally, the catch blocks must all follow each other, without any other statements or blocks in between. Also, the order in which the catch blocks appear matters. For now just know this. We will see more in detail about their order a little bit later.Execution of the guarded region starts at line 2. If the program executes all the way past line 5 with no exceptions being thrown, execution will transfer to line 15 and continue downward. However, if at any time in lines 2 through 5 (the try block) an exception is thrown of type DatabaseDownException, execution will immediately transfer to line 7. Lines 8 through 10 will then be executed so that the entire catch block runs, and then execution will transfer to line 15 and continue.Note that if an exception occurred on, say, line 3 of the try block, the rest of the lines in the try block (4 and 5) would never be executed. Once control jumps to the catch block, it never returns to complete the balance of the try block. This is exactly what you want, though. Imagine your code looks something like this pseudocode:try {getTheFileFromOverNetworkreadFromTheFileAndPopulateTable}catch(CantGetFileFromNetwork) {displayNetworkErrorMessage}The preceding pseudocode demonstrates how you typically work with exceptions. Code that's dependent on a risky operation (as populating a table with file data is dependent on getting the file from the network) is grouped into a try block in such a way that if, say, the first operation fails, you won't continue trying to run other code that's also guaranteed to fail. In the pseudocode example, you won't be able to read from the file if you can't get the file off the network in the first place.One of the benefits of using exception handling is that code to handle any particular exception that may occur in the governed region needs to be written only once. Returning to our earlier code example, there may be three different places in our try block that can generate a DatabaseDownException, but wherever it occurs it will be handled by the same catch block (on line 7).
No you can't run in the boundary to catch a ball
use of finally block is optional in java.if u want to clean up ur code (means u want to close any connection)after exception handling then go for finally block.if not then also your code will run fine.so finally block is optional in java.
No. It will run away and you cant catch it then.