Many projects use at least some of them - the Jakarta Commons libraries. Small reusable libraries simplifying the day-to-day work of thousands of java programmers. But over time the jakarta commons project has grown and the number of components makes it harder and harder to keep track. This session will try to give an overview of the components available and how the Jakarta Commons community is organized.

1. Jakarta
Commons
Torsten Curdt
don’t re-invent the wheel

2. Increase
Productivity

3. Re-use to Excel

4. •Faster
•Better designed
•Less time
•Smaller team

5. How did we do it?

6. Know your libraries!

7. Sharing QA

8. Heritage

9. Charter
“Creation of small re-useable
components that can be used across
projects. They are supposed to have as
few dependencies as possible, meant
to be well tested and compatible with
the current de-facto standard version of
the JDK”

10. Growth
Sandbox
Proper Dormant

11. Project Stats
45
Sandbox
34 Proper
34 38 Dormant
23
11
10
0
Active Inactive

12. Proper

13. CLI
Options options = new Options();
options.addOption(quot;hquot;, false, quot;display usagequot;);
CommandLine line = parser.parse(options, args);
if(line.hasOption(quot;hquot;)) {
HelpFormatter f = new HelpFormatter();
f.printHelp(quot;myprogramquot;, options);
...

14. Collections
Map map = new CaseInsensitiveMap();
map.put(quot;Onequot;, quot;Onequot;);
map.get(quot;ONEquot;);
Map colorMap = MapUtils.toMap(new String[][] {{
{quot;redquot;, quot;#FF0000quot;},
{quot;greenquot;, quot;#00FF00quot;},
{quot;bluequot;, quot;#0000FFquot;}
});

15. Email
SimpleEmail email = new SimpleEmail();
email.setHostName(quot;mail.myserver.comquot;);
email.addTo(quot;jdoe@somewhere.orgquot;, quot;John Doequot;);
email.setFrom(quot;me@apache.orgquot;, quot;Mequot;);
email.setSubject(quot;Test messagequot;);
email.setMsg(quot;A simple test of commons-emailquot;);
email.send();

16. IO
InputStream in;
OutputStream out;
IOUtils.copy(in, out);
...
byte[] data = IOUtils.toByteArray(in);

17. JXPath
XPathContext context =
JXPathContext.newContext(dom);
String value = (String)
context.getValue(quot;/my/xpath/to/valuequot;);

18. Lang
String s = “Apache Jakarta Commons”;
StringUtils.right(s, 7); // “Commons”
String n = “0”;
StringUtils.leftPad(s, 4, ‘0’); // “0000”

19. Logging
public class C {
private Log log = LogFactory.getLog(C.class);
...
if (log.isDebugEnabled()) {
log.debug(quot;log messagequot;);
}

20. Net
NNTPClient client = new NNTPClient();
client.connect(quot;news.server.netquot;);
NewsgroupInfo[] = client.listNewsgroups();
client.disconnect();

21. Primitives
ArrayByteList list = new ArrayByteList();
list.add(byte);
list.removeElementAt(index);
byte[] bytes = list.toArray();

22. VFS
FileSystemManager fs = VFS.getManager();
FileObject jar = fs.resolveFile(
quot;jar:lib/aJarFile.jarquot; );
FileObject[] childs = jar.getChildren();
for (int i=0; i < childs.length; i++ ) {
...

23. Overview
attributes, beanutils, betwixt, chain,
cli, codec, collections, configuration,
daemon, dbcp, dbutils, digester,
discovery, el, email, fileupload,
httpclient, io, jelly, jexl, jxpath, lang,
launcher, logging, math, modeler,
net, pool, primitives, scxml,
transaction, validator, vfs

24. Sandbox

25. CSV
String[][] data = CSVParser.parse(string);
CSVParser parser = new CSVParser(reader,’;’);
String[][] data = parser.getAllValues();

26. Exec
OutputStream out;
OutputStream error;
CommandLine cl = new CommandLineImpl();
cl.setExecutable(quot;path/to/exequot;);
cl.addArgument(quot;argquot;);
exec.execute(cl, out, error);

27. Javaflow
class MyRunnable implements Runnable {
public void run() {
for(int i=0; i<10; i++ )
Continuation.suspend();
}}
Continuation c = Continuation.startWith(
new MyRunnable());
Continuation d = Continuation.continueWith(c);
...

28. JCI
JavaCompiler compiler =
new EclipseJavaCompiler();
ResourceStore store =
new MemoryResourceStore();
CompilationResult result = compiler.compile(
new String[] { quot;org/MyClass.javaquot; },
new FileResourceReader(directory),
store );

29. OpenPGP
keyRing = new BouncyCastleKeyRing(
secret, public, password);
signer = new BouncyCastleOpenPgpSigner();
signer.detachedSign(
fileInputStream
signatureOutputStream,
keyId,
keyRing,
true );

30. Proxy
o = (MyObject) new CglibProxyFactory()
.createInterceptorProxy(
new MyObjectImpl(),
new LoggingInterceptor(log),
new Class[]{ MyObject.class });
o.test(”test”);
[DEBUG] - BEGIN test(test)
[DEBUG] - END test()

31. Overview
compress, csv, exec,
i18n, id, javaflow, jci,
openpgp, pipeline,
proxy

32. Dormant

33. Overview
benchmark, cache, clazz, codec-
mulipart, combo, contract, events,
feedparser, filters, functor, grant,
graph2, http, jex, jjar, jpath, jrcs, jux,
latka, mapper, messenger, pattern,
periodicity, reflect, resources, rupert,
scaffold, services, servlet,
simplestore, tbm, test, threading,
threadpool, workflow, xmlio, xmlunit,
xo

34. Not invented here

35. We need you!

36. Thanks!