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GeneralRe: what does this mean? Pin
Cedric Moonen31-Jan-11 20:23
Cedric Moonen31-Jan-11 20:23 
GeneralRe: what does this mean? Pin
Richard MacCutchan31-Jan-11 22:07
mveRichard MacCutchan31-Jan-11 22:07 
AnswerRe: what does this mean? Pin
bhavitk15-Feb-11 4:06
bhavitk15-Feb-11 4:06 
Questionerror in infix to postfix conversion [modified] Pin
WindowsVsLinux28-Jan-11 3:01
WindowsVsLinux28-Jan-11 3:01 
AnswerRe: error in infix to postfix conversion Pin
Richard MacCutchan28-Jan-11 3:30
mveRichard MacCutchan28-Jan-11 3:30 
GeneralRe: error in infix to postfix conversion Pin
WindowsVsLinux28-Jan-11 19:30
WindowsVsLinux28-Jan-11 19:30 
GeneralRe: error in infix to postfix conversion Pin
Richard MacCutchan28-Jan-11 21:18
mveRichard MacCutchan28-Jan-11 21:18 
AnswerRe: error in infix to postfix conversion Pin
jschell29-Jan-11 10:39
jschell29-Jan-11 10:39 
WindowsVsLinux wrote:
but in output i am getting null


That can only happen in an expression that actually does something with output.

You can debug this by putting a print BEFORE each assignment to output and printing ALL of the values that you use in the expression.

You use output 4 times.

1. private String output="";
2. output=output+ch;
3. output=output+ch1;
4. output=output+stack.pop();

1 cant be null.
2/3 would require that ch/ch1 are null. But both are char data types. And that data type cannot be null.

So that only leaves 4.

I can't be sure about what is happening with 4 but it certainly looks like you have a lot of pop() calls just before that. And since pop() removes the item on the stack I am not sure what you think is going into output.
GeneralRe: error in infix to postfix conversion Pin
WindowsVsLinux30-Jan-11 5:36
WindowsVsLinux30-Jan-11 5:36 
GeneralRe: error in infix to postfix conversion Pin
jschell30-Jan-11 9:46
jschell30-Jan-11 9:46 
QuestionPDF Annotator Pin
Civic0627-Jan-11 15:23
Civic0627-Jan-11 15:23 
AnswerRe: PDF Annotator Pin
David Skelly27-Jan-11 22:30
David Skelly27-Jan-11 22:30 
GeneralRe: PDF Annotator Pin
Civic0627-Jan-11 23:07
Civic0627-Jan-11 23:07 
GeneralRe: PDF Annotator Pin
Richard MacCutchan28-Jan-11 1:37
mveRichard MacCutchan28-Jan-11 1:37 
GeneralRe: PDF Annotator Pin
David Skelly28-Jan-11 2:09
David Skelly28-Jan-11 2:09 
QuestionChanging the CSS properties of a menu bar. Pin
Douglas Kirk24-Jan-11 20:42
Douglas Kirk24-Jan-11 20:42 
AnswerRe: Changing the CSS properties of a menu bar. Pin
Richard MacCutchan24-Jan-11 21:25
mveRichard MacCutchan24-Jan-11 21:25 
GeneralRe: Changing the CSS properties of a menu bar. Pin
Douglas Kirk24-Jan-11 21:38
Douglas Kirk24-Jan-11 21:38 
Question.properties file added to database Pin
pancakeleh23-Jan-11 17:07
pancakeleh23-Jan-11 17:07 
AnswerRe: .properties file added to database Pin
David Skelly23-Jan-11 22:18
David Skelly23-Jan-11 22:18 
GeneralRe: .properties file added to database [modified] Pin
pancakeleh24-Jan-11 15:46
pancakeleh24-Jan-11 15:46 
GeneralRe: .properties file added to database Pin
Richard MacCutchan24-Jan-11 21:27
mveRichard MacCutchan24-Jan-11 21:27 
GeneralRe: .properties file added to database Pin
David Skelly24-Jan-11 22:18
David Skelly24-Jan-11 22:18 
GeneralRe: .properties file added to database Pin
pancakeleh24-Jan-11 22:42
pancakeleh24-Jan-11 22:42 
GeneralRe: .properties file added to database Pin
TorstenH.25-Jan-11 2:12
TorstenH.25-Jan-11 2:12 

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