Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>If you want a method to use an object you have as a local variable you can pass its as an argument. This is standard practice in just about every language I can think of. However instead of passing the FileInputStream it is better to pass the file name in camelCase</p> <pre><code>// in main process(requestFile, responseFile, logFile); // later public static void process(String requestFile, String responseFile, String logFile) throw IOException { //Connect to the Request Input File FileInputStream requestIn = new FileInputStream(requestFile); //Connect to the Response Output File FileOutputStream responseOut = new FileOutputStream(responseFile); //Connect to the Request/Response Log File FileOutputStream logOut = new FileOutputStream(logFile); requestIn.close(); responseOut.close(); logOut.close(); } </code></pre> <blockquote> <p>I get a bunch of "symbol not found" error messages. </p> </blockquote> <p>Because a local variable is local to the scope i.e. the method it is in. You can't use it in another method.</p> <blockquote> <p>Again, if I put "public" in front of the file I/O constructors, I get the Illegal expression message.</p> </blockquote> <p>Because public fields cannot be defined in a method, they have to be define outside a method, usually at the start of the class.</p> <blockquote> <p>Is there any way out of this ??? </p> </blockquote> <p>Reading a few tutorials <a href="http://www.google.com/search?q=java+turorials" rel="nofollow">http://www.google.com/search?q=java+turorials</a> 11 million results, or working example <a href="http://www.google.com/search?q=java+examples" rel="nofollow">http://www.google.com/search?q=java+examples</a> 25 million results </p> <blockquote> <p>Why the java compiler insists on the program handling file-not-found errors is beyond me. I mean there's already the If file_object.exists() method... IF the file's NOT there..the OS will let you know. </p> </blockquote> <p>It does let you know by throwing a FileNotFoundException. What do you expect it to do?</p> <blockquote> <p>All ANY application program(OOP or otherwise) does when it comes to I/O of any kind is to make a request to the underlying OS. </p> </blockquote> <p>And the OS can return an error which you need to be able to handle.</p>
    singulars
    1. This table or related slice is empty.
    1. POHow best to make "accessable" File I/O Stream constructors (channel & ByteBuffer also)
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USPeter Lawrey
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POHow best to make "accessable" File I/O Stream constructors (channel & ByteBuffer also)
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    1. COHi Peter, thanks very much for your insight. However, what I meant was I don't see the need for the compiler to reject the code because one doesn't have a "File-Not-Found" "handler". Take COBOL for instance. While COBOL will return File I/O exceptions to the calling application, IF you don't code any File I/O exception logic, the COBOL compiler doesn't "reject" your code. I think that's where the java compiler goes "overboard"... runtime exceptions... the compiler should ONLY check syntax.
      singulars
      1. PO
      1. USGuy Rich
    2. CO@Guy Rich, Many people agree with you. However from years of working with checked exception I would much prefer the compiler force you to think about and address in code certain errors which can occur. You only need to throw or catch IOException (as its a super class of FileNotFoundException) and a decent IDE can make it much easier to manage your exceptions so it not as much an overhead that it used to me. I can understand developers not wanting to think about error handling, but that just tell me its a good idea.
      singulars
      1. PO
      1. USPeter Lawrey
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload