 |  |  |  |  |  |  |  |
Reading a txt file into a swing component
Thread Solved |
Hello, I was hoping that someone might be able to help me with this program:
I am getting an error starting at line 205 with the variable "lastName". I am getting the 'cannont resovle symbol' error with this variable amd the other array variable I had set up to read the columns of a text file. I am thinking that since the technique of reading the text file is embedded in its own prodecure that maybe the variables are not recongized by other procedures.
I would appreciate any help that anyone can provide. I am at a loss as to what to do. Here is a copy of the text file I am using. Thanks in advance.
Java Syntax (Toggle Plain Text)
I am getting an error starting at line 205 with the variable "lastName". I am getting the 'cannont resovle symbol' error with this variable amd the other array variable I had set up to read the columns of a text file. I am thinking that since the technique of reading the text file is embedded in its own prodecure that maybe the variables are not recongized by other procedures.
I would appreciate any help that anyone can provide. I am at a loss as to what to do. Here is a copy of the text file I am using. Thanks in advance.
Java Syntax (Toggle Plain Text)
•
•
Join Date: Jan 2008
Posts: 3,817
Reputation: 
Solved Threads: 501
Line 205? Where's line 205? Please repost using Java code tags. which will add line numbers, or highlight line 205 in red.
[code=JAVA]
// paste code here
[/code]
[code=JAVA]
// paste code here
[/code]
Sorry about that. I didn't think about adding the line numbers. Here it is again...hopefully.
Java Syntax (Toggle Plain Text)
•
•
Join Date: Jan 2008
Posts: 3,817
Reputation:
Solved Threads: 501
You have a scoping issue. You define lastName in function readFile. lastName is not a class data member, so it goes out of scope once the readFile function is over. You try to use it in the addTextToTextPane function. You can't do that. If you intend lastName to be global/class variable, you should declare it at a global scale. Anything initially declared inside of a function is not a global/class variable.
Last edited by VernonDozier; Nov 4th, 2008 at 4:33 pm.
That's the conclusion that I was thinking about also...I am at a lost as to the best way to go about making those array variables global...I dont suppose you have any suggestions? One example would be a good start for me to learn from.
•
•
Join Date: Sep 2008
Posts: 1,574
Reputation:
Solved Threads: 197
java Syntax (Toggle Plain Text)
From a method inside the class with an instance of anExample:
You can refer to (use) obj and obj3.
From a static method inside the class without an instance of anExample:
You can use obj2 and obj4. Being static means the class has one copy of them that is shared by the entire class.
From a method inside a different class, with an instance of anExample:
You can refer to obj3
From a method inside a different class, without an instance of anExample:
you can refer to obj4
So the answer to your question would be the following, although I didn't look at your code. Either use a public or protected variable in your main driver class (the one thats run when you first start the program), use a private instance variable and provide accessors and mutators, or you could use a static variable. In either case, if you wanted easy access to the variable in both of your classes, consider using constructors that take the parameter as an argument.
Last edited by BestJewSinceJC; Nov 4th, 2008 at 5:02 pm.
Thanks for the pointers...I think I am going to try something like this:
From what I see in this example, I will go ahead and implement something similar and rewrite my array varaiables accordingly......I'll reply with the results.
Java Syntax (Toggle Plain Text)
From what I see in this example, I will go ahead and implement something similar and rewrite my array varaiables accordingly......I'll reply with the results.
•
•
Join Date: Sep 2008
Posts: 1,574
Reputation:
Solved Threads: 197
Yes, the above example will work, as long as you declare x properly. It should say public static int x = 37;
•
•
Join Date: Jan 2008
Posts: 3,817
Reputation:
Solved Threads: 501
•
•
•
•
Originally Posted by dbwalters 
Thanks for the pointers...I think I am going to try something like this:
Java Syntax (Toggle Plain Text)
From what I see in this example, I will go ahead and implement something similar and rewrite my array varaiables accordingly......I'll reply with the results.
JAVA Syntax (Toggle Plain Text)
Now you can use the variables in lines 3 - 11 globally. Or again, if you are only calling readFile once, you can put the
new commands in the constructor. •
•
Join Date: Sep 2008
Posts: 1,574
Reputation:
Solved Threads: 197
@ Vernon: I got the impression that he isn't creating a new class, he was just giving an example of what he thought the concepts were, and he's going to use those concepts in the class he currently has. No?
Last edited by BestJewSinceJC; Nov 4th, 2008 at 5:26 pm.
 |
Similar Threads
- Homework Help (Java)
- Homework Help (Community Introductions)
Other Threads in the Java Forum
- Previous Thread: Accessing classes from xml settings
- Next Thread: convert nested for loop into nested while loop
| Thread Tools | Search this Thread |
You need to join our community in order to build your list of favorite forums. You can visit the forum index for a listing of all forums.
Related Forum Features
Latest Java Posts
- Today's Posts
- Unanswered Threads
android api applet application apps array arrays automation awt bidirectional binary birt bluetooth businessintelligence busy_handler(null) card chat class classes client code collision columns component constructor database designadrawingapplicationusingjavajslider draw eclipse error errors eventlistener exception expand fractal game givemetehcodez graphics gui guidancer html ide image inetaddress input integer intellij j2me java javafx javamicroeditionuseofmotionsensor javaprojects jme jni jpanel jtree julia linux list loop machine map method methods mobile mobiledevelopmentcreatejar myaggfun netbeans newbie oracle parsing plazmic print problem program programming project recursion scanner server set sharepoint smart sms smsspam sort sortedmaps sql string subclass support swing textfield threads tree trolltech unlimited utility webservices windows
