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-   -   How to remove this issue about NumberFormatException? (http://www.velocityreviews.com/forums/t957039-how-to-remove-this-issue-about-numberformatexception.html)

bluestar 01-29-2013 08:09 AM

How to remove this issue about NumberFormatException?
 
Hi, all:

I am rookie for coding java and I have one question about queue
class

I use one queue class: ArrayBlockingQueue to save/get my data

I read some data from HW and save into one ArrayBlockingQueue, and
then get from this ArrayBlockingQueue when needing. But it has one
error message: <java.lang.NumberFormatException: Invalid int:
"ffffff94"> when doing poll function

My simple code is below

private ArrayBlockingQueue<Byte> iReadQueueArray = new
ArrayBlockingQueue<Byte>(READBUF_SIZE, true);

byte[] rbuf = new byte[256];

iReadCnt = readfromHW(rbuf, rbuf.length); <---read data from
HW
ret = iReadQueueArray.offer( Byte.valueOf( (rbuf[i]&0xFF) ));

//-----------------------------------------------------------------------//
public int read(byte[] buf) {
Byte mdata;
...
mdata = (Byte)iReadQueueArray.poll(); <---occur error when
polling some data
if( mdata!=null ) {
buf[i] = (byte) (mdata.byteValue()&0xFF);
}
...
return 0;
}
//-----------------------------------------------------------------------//

How to modify offer data into the queue and poll data from the
queue?

Thank you for your help!

BR,
Alan

bluestar 01-29-2013 09:09 AM

Re: How to remove this issue about NumberFormatException?
 
I change queue to ArrayBlockingQueue<Integer> iReadQueueArray = new
ArrayBlockingQueue<Integer>(READBUF_SIZE, true);
But still it has the same issue

ret = iReadQueueArray.offer(new Integer((int) (rbuf[i]&0xFF)));

//-----------------------------------------------------------------------//
public int read(byte[] buf) {
Integer mdata;
...
mdata = (Integer)iReadQueueArray.poll();
if( mdata!=null ) {
buf[i] = (byte) (mdata.intValue()&0xFF);<---occur error when
casting some data
}
...
return 0;
}
//-----------------------------------------------------------------------//

Roedy Green 01-29-2013 10:15 AM

Re: How to remove this issue about NumberFormatException?
 
On Tue, 29 Jan 2013 01:09:06 -0800 (PST), bluestar
<bluestar8783@gmail.com> wrote, quoted or indirectly quoted someone
who said :

>mdata.intValue()&0xFF);<---occur error when


You want to see what mdata is. use .getClass()

from there drill down to find the data.

As far as I know, NumberFormatExceptions only happen when you convert
from String to binary.
I can't see why or where you would be doing that.
--
Roedy Green Canadian Mind Products http://mindprod.com
The first 90% of the code accounts for the first 90% of the development time.
The remaining 10% of the code accounts for the other 90% of the development
time.
~ Tom Cargill Ninety-ninety Law

Arved Sandstrom 01-29-2013 10:38 AM

Re: How to remove this issue about NumberFormatException?
 
On 01/29/2013 06:15 AM, Roedy Green wrote:
> On Tue, 29 Jan 2013 01:09:06 -0800 (PST), bluestar
> <bluestar8783@gmail.com> wrote, quoted or indirectly quoted someone
> who said :
>
>> mdata.intValue()&0xFF);<---occur error when

>
> You want to see what mdata is. use .getClass()
>
> from there drill down to find the data.
>
> As far as I know, NumberFormatExceptions only happen when you convert
> from String to binary.
> I can't see why or where you would be doing that.
>

Number objects are more binary than String objects? Who knew?

An NFE is simply if the String format expected by a conversion to a
numeric type is not correct.

As for where it's happening, it's in the error message. I'd want to see
more of the program myself.

AHS

Roedy Green 01-30-2013 12:55 PM

Re: How to remove this issue about NumberFormatException?
 
On Tue, 29 Jan 2013 06:38:18 -0400, Arved Sandstrom
<asandstrom2@eastlink.ca> wrote, quoted or indirectly quoted someone
who said :

>Number objects are more binary than String objects? Who knew?


"123" is a string of characters. 3 x 16-bit unicodes. int i=123 is
stored internally as 32-bit binary at run-time as is new Integer( 123
) in a protective object wrapper.

Perhaps it is my age, but it is a long standing tradition to refer
call the process as "converting character/a/alpha/ascii to binary".

Number is a general term that includes byte, int, float, double,
packed decimal, fixed length char numerics. (Think COBOL PL/I). In
Java, Number is an abstract class with ten implementations.
--
Roedy Green Canadian Mind Products http://mindprod.com
The first 90% of the code accounts for the first 90% of the development time.
The remaining 10% of the code accounts for the other 90% of the development
time.
~ Tom Cargill Ninety-ninety Law

Lew 01-30-2013 04:35 PM

Re: How to remove this issue about NumberFormatException?
 
Roedy Green wrote:
> Arved Sandstrom wrote, quoted or indirectly quoted someone who said :
>>Number objects are more binary than String objects? Who knew?

>
> "123" is a string of characters. 3 x 16-bit unicodes. int i=123 is
> stored internally as 32-bit binary at run-time as is new Integer( 123
> ) in a protective object wrapper.


And every real programmer knows that both are binary representations at their heart.

That's all he's saying.

> Perhaps it is my age, but it is a long standing tradition to refer
> call the process as "converting character/a/alpha/ascii to binary".


A loose description. Arved's was precise.

> Number is a general term that includes byte, int, float, double,
> packed decimal, fixed length char numerics. (Think COBOL PL/I). In
> Java, Number is an abstract class with ten implementations.


Ten implementations that you know of. There might be more.

--
Lew

Roedy Green 01-31-2013 12:21 PM

Re: How to remove this issue about NumberFormatException?
 
On Wed, 30 Jan 2013 08:35:11 -0800 (PST), Lew <lewbloch@gmail.com>
wrote, quoted or indirectly quoted someone who said :

>A loose description. Arved's was precise


He was just playing lawyerly putdown games.
--
Roedy Green Canadian Mind Products http://mindprod.com
The first 90% of the code accounts for the first 90% of the development time.
The remaining 10% of the code accounts for the other 90% of the development
time.
~ Tom Cargill Ninety-ninety Law


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