Josh Highley | 14 Oct 23:20 2014

[Imaging] sanselan dependency missing Imaging class

Per the main imaging page, I've added sanselan as a dependency to my


However, this does not include the org.apache.commons.imaging.Imaging class
referenced in the javadocs and the image read example:

I can't find commons-imaging in a Maven repo.  What information am I


Stefan Bodewig | 10 Oct 18:16 2014

[ANN] Apache Commons Compress 1.9 Released

The Apache Commons Team is pleased to announce the release of Apache
Commons Compress 1.9.

Version 1.9 adds support for raw DEFLATE streams without GZIP framing.
In addition it fixes bugs in the 7z and tar packages and may improve
checking for the presence of the XZ for Java library.

The Apache Commons Compress Library defines a Java API for working with
ar, cpio, tar, zip, 7z, arj, dump, gzip, pack200, bzip2, lzma, snappy,
Z, xz and deflate files.

Source and binary distributions are available for download from the
Apache Commons download site:

When downloading, please verify signatures using the KEYS file available
at the above location when downloading the release.

Changes in this version include:

New features:
o Added support for DEFLATE streams without any gzip framing.
  Issue: COMPRESS-263.
  Thanks to Matthias Stevens.

Fixed Bugs:
o When reading 7z files unknown file properties and properties of type
  kDummy are now ignored.
(Continue reading)

Stefan Bodewig | 10 Oct 13:19 2014

[compress] ZIP Encoding and Windows Compressed Folders

Hi all

we wrote back
when Windows XP was state of the art.  In there we claim the "compressed
folders" feature didn't recognize the language encoding flag and advised
people to use the platform's native encoding when targeting Windows.

A discussion on a different list made me re-check on a Windows 7 VM and
it seems as if "compressed folders" properly extracted some of my
filenames, but not all of them (Umlauts seemed to work, the Euro glyph

I haven't got access to a Windows 8 box at all.

Can anybody with access to a Windows more modern than Windows XP please
try to create a ZIP archive using Compress' ZipArchiveOutpuStream with
UTF-8 encoding, language encoding flag set and with some filenames that
use Unicode characters outside of the Windows system's platform encoding
- and see whether "compressed folders" extracts them properly?


Ate Douma | 10 Oct 09:18 2014

[SCXML] Heads-up for Commons SCXML 2.0-SNAPSHOT users: <send> action updated with breaking changes

Hi Commons SCXML users of the latest 2.0-SNAPSHOT (trunk),

Be warned that if you update to the latest committed state in trunk, you likely 
will have to update your existing SCXML documents when using the <send> action.

The <send> action attributes now have been aligned with the latest SCXML 
specification, see:

This required some breaking changes in naming and handling of some of these 

Please review before doing a 
next svn up... (you have been warned)


arnout cator | 9 Oct 17:43 2014

correct estimate of the disk cache size

I have noticed that our JCS disk cache seems to grow larger than I expect
it to be. In particular it is double the size I expect it to be. Does
anyone know how we can estimate the size of the disk cache? Let’s say I
have a very simple configuration in which I have 1 region defined. I have
set a Maximum key size of 1000. Would the following calculation be a
correct estimate of the disk cache size?

Maximum Key Size x Average Object Size = Cache Size

1000 x 50 KB = 50 MB

In my environment I am seeing the cache has grown much larger and I am
trying to understand why that might be. I have the following configuration









(Continue reading)

arnout cator | 9 Oct 16:02 2014

JCS cache benchmarking for performance


I have the following question:

What would be the best practice in monitoring JCS caching performance for
production web applications? I am looking for a way to collect data and
then give advice on sizing of web applications that heavily use JCS for
caching of java objects.
Thufir | 4 Oct 02:50 2014


is this unmaintained?  dead?  stable?
Luke Lindsay | 3 Oct 13:40 2014

[math] DerivativeStructure constants


I am using the apache math DerivativeStructure framework.  In general
I find it very useful, however sometimes I find having to specify the
number of free parameters and order for what are essentially constants
makes code complex.

I often find myself writing code similar to the following.

 public DerivativeStructure sum(DerivativeStructure[] values){
        DerivativeStructure sum = new
        for (int i = 0; i < values.length; i++) {
            sum = sum.add(values[i]);
        return sum;


 public DerivativeStructure sum(DerivativeStructure[] values, int
params, int order){
        DerivativeStructure sum = new DerivativeStructure(params, order);
        for (int i = 0; i < values.length; i++) {
            sum = sum.add(values[i]);
        return sum;

(Continue reading)

R.C. Hoekstra | 2 Oct 09:53 2014

[scxml] passing datamodel elements into method call

Hi list, Hi people  <at>  scxml commons,

Can I pass datamodel nodes to a rootContext var, in order to process it in java?

like this:
<target event="bla" cond="agent.check(datamodelNodeRef)" .../>,
* agent is an object of a java class made available to the RootContext, having a check method returning
Boolean. I want this check method to evaluate the datamodelNode, in order to return true or false
depending on elements.
* datamodelNodeRef is a reference to some node in the datamodel.

I managed to pass final nodes as string here, like this:

<cs:var name="treatment1Name"  expr="Data(treatmentData,'treatments/treatment[1]/name')" />,
<transition ... cond="agent.check(treament1Name)"...

where the treatments/treatment[1]/name is a final node.

However, I would like to pass non final nodes of the datamodel, but everything seems to be evaluated as
strings first, before it is passed into the method of the context var.

Hope you can give me a clue.

And, if these kind of constructions are possible, how would they do in terms of performance?

thanks, Rinke

Ashish Chaudhary | 1 Oct 10:46 2014


I am getting this error  *"INFO: Maximum number of threads (200) created
for connector with address null and port 8080"*  on prod in approximately
every 7-8 days. So to debug this issue I downloaded the thread dump file.
This file has following thread state 100 times:

"http-8080-198" daemon prio=10 tid=0x08a62c00 nid=0x3a78 in Object.wait()
   java.lang.Thread.State: WAITING (on object monitor)
    at java.lang.Object.wait(Native Method)
    - waiting on <0x87097728> (a
    at java.lang.Object.wait(
    - locked <0x87097728> (a

My understanding is that there is some memory leak or the connection
objects are not enough and because of this every call waits for new MySQL
connection from the pool and it just hangs there and the thread associated
with this MySQL call also waits. And this leads to this issue *"INFO:
Maximum number of threads (200) created for connector with address null and
port 8080"*

So my questions are:

    Is this exception because of mysql connection pool? If yes, what should
I do to solve it? My MAX-Active value is 50 and MinIdle value is 1.

    If this is not the case then how can I know which functionality are
(Continue reading)

Matt Benson | 30 Sep 16:55 2014

[ANNOUNCEMENT] Apache Commons Weaver 1.1 Released

The Apache Commons team is pleased to announce the release of:

Apache Commons Weaver 1.1

Apache Commons Weaver provides an easy way to enhance compiled Java
classes by generating ("weaving") bytecode into those classes.

The release notes can be reviewed at:

Distribution packages can be downloaded from:

When downloading, please verify signatures using the KEYS file available at:

The release is also available in the central Maven repository:

The Apache Commons Team