Re: [collections] Name that data structure
Wendy, you could most certainly use a LRUMap with a fixed size. Give
each item a unique key and let the Map take care of uniqueness. LRUMap
will take care of discarding the least recently used entry once it
reached the maximum defined size, and the Iterator returns most recently
used to least recently used. This would be the easiest way to do this,
by far.
Or you could do something that takes more work, but I think it more fun:
Define a Predicate:
import java.util.Collection;
mport org.apache.commons.collections.Predicate;
public class UniqueInCollection implements Predicate {
private Collection collection;
public UniqueInCollection(Collection collection) {
this.collection = collection;
}
public boolean evaluate(Object o) {
return !collection.contains( o );
}
}
Then use a CircularFifoBuffer married to the Predicate. Only downside
is that you have to catch IllegalArgumentException throw by
PredicatedBuffer:
import java.util.Iterator;
import org.apache.commons.collections.Buffer;
import org.apache.commons.collections.Predicate;
import org.apache.commons.collections.buffer.CircularFifoBuffer;
import org.apache.commons.collections.buffer.PredicatedBuffer;
public class RecentlyVisited {
public static void main(String[] args) {
Buffer buffer = new CircularFifoBuffer(5);
Predicate unique = new UniqueInCollection(buffer);
Buffer recentVisited = PredicatedBuffer.decorate(buffer, unique);
add( recentVisited, Page 1 );
add( recentVisited, Page 2 );
add( recentVisited, Page 3 );
add( recentVisited, Page 4 );
add( recentVisited, Page 1 );
add( recentVisited, Page 2 );
add( recentVisited, Page 1 );
add( recentVisited, Page 21 );
add( recentVisited, Page 22 );
add( recentVisited, Page 1 );
Iterator i = buffer.iterator();
while( i.hasNext() ) {
String value = (String) i.next();
System.out.println( value );
}
}
public static void add(Buffer recentVisited, String page) {
try {
recentVisited.add( page );
} catch( IllegalArgumentException iae ) {
// do nothing, buffer will complain if predicate fails.
}
}
}
Mattias Jiderhamn wrote:
Possibly it could also be a MRU (Most Recently Used) cache.
At 2005-07-03 23:39, you wrote:
I'd say you were looking for an ordinary priority queue, where the
priority=the timestamp. Try the Heap class.
Sincerely,
Silas Snider
On 7/3/05, Wendy Smoak [EMAIL PROTECTED] wrote:
I'm looking through the Collections API, but not finding exactly
what I
want... hoping someone who's more familiar with it can point me in
the right
direction.
What I'm trying to do is more or less what you see on catalog sites
where
they'll list the most recent items you've looked at, newest on
top. So it's
ordered (List), but has no duplicates (Set), and I need to have a
max size.
ListOrderedSet is almost there, except that it retains the 'old'
position if
you add the same item again. (And has no max length.)
So... before I either write it myself or extend ListOrderedSet to
make it do
what I want, does anyone have another suggestion? And what would
_you_ call
it?
Thanks,
Wendy Smoak
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Re: [collections] Name that data structure
Tim O'Brien wrote:
Wendy, you could most certainly use a LRUMap with a fixed size. Give
each item a unique key and let the Map take care of uniqueness.
LRUMap will take care of discarding the least recently used entry once
it reached the maximum defined size, and the Iterator returns most
recently used to least recently used. This would be the easiest way
to do this, by far.
Sorry, hit send too quickly, so that code compared to the LRUMap solution:
Map map = new LRUMap(5);
map.put( Page 1, );
map.put( Page 2, );
map.put( Page 3, );
map.put( Page 4, );
map.put( Page 5, );
map.put( Page 6, );
map.put( Page 7, );
map.put( Page 8, );
map.put( Page 9, );
map.put( Page 1, );
Iterator i = map.keySet().iterator();
while (i.hasNext()) {
String value = (String) i.next();
System.out.println(value);
}
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DBCP: jocl and Configuration Parameters for ObjectPools
Is there a way to include the various configuration parameters for GenericObjectPool and GenericKeyedObjectPool directly in a .jocl file? For instance, maxActive, timeBetweenEvictionRunsMillis, and testWhileId. Must these parameters be set explicitly on the pools or can they be configured in the .jocl file somehow? Looking for some example xml on any pool parameters if possible. thanks, Mike - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: [csv] Creating a CSV component
On 10:28 Sun 19 Jun , robert burrell donkin wrote: the discussions have moved onto dev but no consensus has been reached as yet. On Tue, 2005-06-14 at 18:14 +0300, Emmanouil Batsis wrote: Just wanted to ask whether you folks have chosen what to use for this. Is there any more information on this? My situation has changed and if anyone else wants to work on something under the cvs4j.sf.net umbrella feel free to contact me and I'll transfer maintainership over to you. Personally I'd still prefer to see it under commons. -- Don Seiler [EMAIL PROTECTED] Public Key: http://pgp.mit.edu:11371/pks/lookup?op=getsearch=0xFC87F041 Fingerprint: 0B56 50D5 E91E 4D4C 83B7 207C 76AC 5DA2 FC87 F041 pgpPnby6BJAbR.pgp Description: PGP signature
FileUploadException - the request was rejected because it's size is unknown
I am using the FileUpload 1.1 library in Weblogic 8.1 SP4, and am trying to
get uploading to work in portlets. Whenever I try to parse my multipart
content, I get an exception with the message the request was rejected
because it's size is unknown.
Here are some relevant code snippets.
public void processAction(ActionRequest request, ActionResponse
response) throws PortletException
{
if (PortletFileUpload.isMultipartContent(request))
{
DiskFileItemFactory factory = new DiskFileItemFactory();
PortletFileUpload upload = new PortletFileUpload(factory);
try
{
List fileItems = upload.parseRequest(request);
FileItem item = (FileItem)fileItems.iterator().next();
File uploadedFile = new File(type + item.getName());
item.write(uploadedFile);
}
catch (Exception ex)
{
System.out.println(EXCEPTION: File upload request error:
+ ex.getMessage());
//ex.printStackTrace();
return;
}
...
My jsp file contains:
form action=portlet:actionURL / method=post
enctype=multipart/form-data
table width=100% cellspacing=0 cellpadding=3
tr
tdTitle/td
td input type=text name=title/td
/tr
tr
tdDescription/td
td input type=text name=description/td
/tr
tr
tdFile/td
td input type=file name=upfile /td
/tr
/table
input type=submit name=doUpload value=upload/
input type=submit name=cancel value=cancel/
/form
I have tried this with size set and unset in the input type=file
section.
I have tried several forums already and gotten no responses. Any
direction/help would be appreciated.
-Guhn Chang
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RE: [betwixt] NullPointerException in 0.7RC1
i tried the test out on RC2 and it still looks good... glenn -Original Message- From: robert burrell donkin [mailto:[EMAIL PROTECTED] Sent: Tuesday, June 28, 2005 3:43 PM To: Jakarta Commons Users List Subject: RE: [betwixt] NullPointerException in 0.7RC1 On Mon, 2005-06-27 at 10:13 -0500, Glenn Goldenberg wrote: hi robert: I updated my local version of Betwixt with the patch and rebuilt. The test works fine now. Thanks for the fix! and thank you for finding the problem and testing the fix! i'm going to go ahead and roll an RC2 very soon. i'd be grateful if you would verify that it's ok (when it's cut). - robert - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Transaction API, ReadWriteLock
I'm trying to use the ReadWriteLock class to acquire a write lock on a file
in a servlet. When I generate multiple threads of the servlet using a WTE
5.1 server in the WSAD 5.1 IDE, I'm not able to get ReadWriteLock to block
other servlet threads after the first servlet thread obtains the lock. I'm
using two IE browser windows to generate the two servlet threads. Below is
ReadWriteLock code I have in the servlet followed by the System.out.println
statements that are generated in the server log file during my test.
ReadWriteLock fileLock = new ReadWriteLock(new File(c:/logRec.txt,
loggerFacade);
try {
System.out.println(before acquiring a lock +
Thread.currentThread());
boolean result =
fileLock.acquireWrite(Thread.currentThread(),Long.MAX_VALUE);
System.out.println(lock result: + result + +
Thread.currentThread());
Thread.sleep(2);
System.out.println(after sleeping + Thread.currentThread());
FileWriter recFile = new FileWriter(c:/logRec.txt, true);
recFile.write(text from testFileTran);
recFile.close();
} catch (InterruptedException e) {
e.printStackTrace(System.err);
} catch (IOException e) {
e.printStackTrace(System.err);
} finally {
fileLock.release(Thread.currentThread());
}
[7/5/05 8:26:03:326 CDT] 7c1477e SystemOut O before acquiring a lock
Thread[Servlet.Engine.Transports : 0,5,main]
[7/5/05 8:26:03:326 CDT] 7c1477e SystemOut O lock result: true
Thread[Servlet.Engine.Transports : 0,5,main]
[7/5/05 8:26:08:384 CDT] 24c3477d SystemOut O before acquiring a lock
Thread[Servlet.Engine.Transports : 1,5,main]
[7/5/05 8:26:08:384 CDT] 24c3477d SystemOut O lock result: true
Thread[Servlet.Engine.Transports : 1,5,main]
[7/5/05 8:26:23:335 CDT] 7c1477e SystemOut O after sleeping
Thread[Servlet.Engine.Transports : 0,5,main]
[7/5/05 8:26:28:382 CDT] 24c3477d SystemOut O after sleeping
Thread[Servlet.Engine.Transports : 1,5,main]
From reviewing the Transaction documentation and mailing list archives, I'm
not able to determine what I'm doing wrong.
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RE: [betwixt] NullPointerException in 0.7RC1
great thanks - robert On Tue, 2005-07-05 at 11:11 -0500, Glenn Goldenberg wrote: i tried the test out on RC2 and it still looks good... glenn -Original Message- From: robert burrell donkin [mailto:[EMAIL PROTECTED] Sent: Tuesday, June 28, 2005 3:43 PM To: Jakarta Commons Users List Subject: RE: [betwixt] NullPointerException in 0.7RC1 On Mon, 2005-06-27 at 10:13 -0500, Glenn Goldenberg wrote: hi robert: I updated my local version of Betwixt with the patch and rebuilt. The test works fine now. Thanks for the fix! and thank you for finding the problem and testing the fix! i'm going to go ahead and roll an RC2 very soon. i'd be grateful if you would verify that it's ok (when it's cut). - robert - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: [DBUtils] BeanHandler has problem retrieving Dates ?
It doesn't need to specifically check for Date because the first thing the method does is an instanceof check. So, if your bean property is a java.util.Date and the JDBC driver returns a java.sql.Date or java.sql.Timestamp the property should get set. David --- Henry Voyer [EMAIL PROTECTED] wrote: Hi everyone I just used DBUtils for a date retreival. And to my astonishement it doesnt get the Dates. I looked in the BasicRowProcessor.isCompatibleType() method, there is no Date reference. Is this normal ? and why? Regards Henry Get Firefox! http://www.mozilla.org/firefox/ Yahoo! Sports Rekindle the Rivalries. Sign up for Fantasy Football http://football.fantasysports.yahoo.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Expressions, Collections, Filtering oh my..
I've got a collection of a JavaBeans, it could be a plain-old-Java collection or a Commons-Collection... Not really a concern... I'm trying to find a way to provide the ability to write a JEXL-like expression that would be applied against the collection of JavaBeans, and be able to retrieve all of the JavaBeans that match that JEXL-like expression. So far, looking at JEXL, it looks like it requires a JexlContext, but I don't see or know how I would adapt my JavaBean properties to this. Is there an out-of-the-binary way of filtering through my JavaBeans, and giving me access to those that match some expression? Thanks. Troy - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Expressions, Collections, Filtering oh my..
JXPath allows you to write XPath expressions and run them against a Collection. -Shawn -Original Message- From: Poppe, Troy [mailto:[EMAIL PROTECTED] Sent: Tuesday, July 05, 2005 4:02 PM To: 'commons-user@jakarta.apache.org' Subject: Expressions, Collections, Filtering oh my.. I've got a collection of a JavaBeans, it could be a plain-old-Java collection or a Commons-Collection... Not really a concern... I'm trying to find a way to provide the ability to write a JEXL-like expression that would be applied against the collection of JavaBeans, and be able to retrieve all of the JavaBeans that match that JEXL-like expression. So far, looking at JEXL, it looks like it requires a JexlContext, but I don't see or know how I would adapt my JavaBean properties to this. Is there an out-of-the-binary way of filtering through my JavaBeans, and giving me access to those that match some expression? Thanks. Troy - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Expressions, Collections, Filtering oh my..
Poppe, Troy wrote: I've got a collection of a JavaBeans, it could be a plain-old-Java collection or a Commons-Collection... Not really a concern... I'm trying to find a way to provide the ability to write a JEXL-like expression that would be applied against the collection of JavaBeans, and be able to retrieve all of the JavaBeans that match that JEXL-like expression. So far, looking at JEXL, it looks like it requires a JexlContext, but I don't see or know how I would adapt my JavaBean properties to this. Is there an out-of-the-binary way of filtering through my JavaBeans, and giving me access to those that match some expression? With commons-collections, the best approach is to write a Predicate instance (typcially an inner class), and use CollectionUtils.filter or PredicateCollection to do the filtering. No specific JEXL handling though. Stephen - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
[DBUtils] QueryRunner.fillStatement is not static
The method 'QueryRunner.fillStatement' is not static even though no instance state is referenced. Could it be officially changed into a static method ? (I need to use this functionality but I don't want to instantiate this class just to use this method). Regards, Elifarley - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
[Net] SocketException - Connection reset
Hello! I keep coming across this problem when using FTP. I am able to successfully retrieve a file from a remote server in passive mode, but afterwards, when I try to logout, I get an IOError caused by a SocketException: Connection reset. There are several ways to work around this problem, but I am wondering if anybody can tell me WHY this happens? Why would a remote server reset the connection after the completion of a get? (Or IS it the remote server that's causing the reset?) Also, why does this happen only sometimes, and not consistently? Any explanation or even a link to relevant doc would be very much appreciated. Cheers, Dave - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
[digester] Digester pinning objects in memory
I am using commons-digester for creating some objects from some xml
files. When I look at this with JProbe Digester (and some other
internal stuff are still referencing the object that is parsed. The
code is as follows, any help would be greatly appreciated:
Digester digester = initializeDigester();
CommissionStatement commissionStatement =
(CommissionStatement)digester.parse(new
StringReader(FileUtils.readFile(file.getAbsolutePath(;
digester.clear();
digester=null;
...snip
clearCommissionStatement(commissionStatement);
private Digester initializeDigester() {
Digester digester = new Digester();
digester.setValidating(false);
digester.addObjectCreate(CommissionStatementVO,CommissionStatement.class);
digester.addObjectCreate(CommissionStatementVO/AgentStatementVO,AgentStatement.class);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/StatementDate,statementDate);
digester.addObjectCreate(CommissionStatementVO/AgentStatementVO/AgentInfoVO,AgentInfo.class);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/FirstName,firstName);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/Name,lastName);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/AgentId,agentId);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/Address1,address1);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/Address2,address2);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/City,city);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/State,state);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/Zip,zip);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/AgentType,agentType);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentInfoVO/DisbursementSource,disbursementSource);
digester.addSetNex(CommissionStatementVO/AgentStatementVO/AgentInfoVO,setAgentInfo,com.equitrust.commissionloader.beans.AgentInfo);
digester.addObjectCreate(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO,AgentStatementDetail.class);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/AgentNumber,agentNumber);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/ProductType,productType);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/FirstName,firstName);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/Name,lastName);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/EffectiveDate,effectiveDate);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/ProcessDate,processDate);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/OwnerName,ownerName);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/PolicyNumber,policyNumber);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/InitialPremium,initialPremium);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/CommissionRate,commissionRate);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/CommissionPremium,commissionPremium);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/Type,commissionType);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO/AmountDue,amountDue);
digester.addSetNext(CommissionStatementVO/AgentStatementVO/AgentStatementLineVO,addAgentStatementDetail,com.equitrust.commissionloader.beans.AgentStatementDetail);
digester.addObjectCreate(CommissionStatementVO/AgentStatementVO/AgentEarningsVO,AgentEarning.class);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentEarningsVO/TaxableIncome,taxableIncome);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentEarningsVO/TaxableIncomeYTD,taxableIncomeYTD);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentEarningsVO/PositivePolicyEarnings,positiveEarnings);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentEarningsVO/NegativePolicyEarnings,negativeEarnings);
digester.addBeanPropertySetter(CommissionStatementVO/AgentStatementVO/AgentEarningsVO/NetPolicyEarnings,netEarnings);
digester.addSetNext(CommissionStatementVO/AgentStatementVO/AgentEarningsVO,setAgentEarning,com.equitrust.commissionloader.beans.AgentEarning);
[CLI] two different versions of commons-cli-1.0.jar?
When you download from http://jakarta.apache.org/site/downloads/downloads_commons-cli.cgi you get cli-1.0.zip which is the original distribution from November 2002 containing commons-cli-1.0.jar corresponding to http://svn.apache.org/repos/asf/jakarta/commons/proper/cli/tags/CLI_1_0/ But if you download http://www.ibiblio.org/maven/commons-cli/jars/commons-cli-1.0.jar or e.g. http://apache.usp.br/java-repository/commons-cli/jars/commons-cli-1.0.jar you get a different archive containg two more classes, OptionValidator and Util. This versions seems to be the one described at http://jakarta.apache.org/commons/cli/apidocs/org/apache/commons/cli/package-summary.html also claiming to be Commons CLI 1.0. Can someone please explain what is going on here? I wonder if there is a tag in svn for the maven version or if it is a snapshot of http://svn.apache.org/repos/asf/jakarta/commons/proper/cli/trunk/ thanks, Jesper _ Log på MSN Messenger direkte på nettet http://webmessenger.msn.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: [digester] Digester pinning objects in memory
On Tue, 2005-07-05 at 16:48 -0500, Matt Goodwin wrote: I am using commons-digester for creating some objects from some xml files. When I look at this with JProbe Digester (and some other internal stuff are still referencing the object that is parsed. The code is as follows, any help would be greatly appreciated: Digester does keep a reference to the root object it creates. You can clear this via a call to: Digester.resetRoot (since 1.7 only). I don't see any other way that Digester could retain references to created objects. However this shouldn't be relevant; after you use the Digester object, there shouldn't be any references to it. So the Digester will get garbage-collected and therefore the root object isn't prevented from being garbage-collected. It would therefore appear that your code is holding on to the Digester reference after it has been used; if you fix this then your problem should go away anyway. Regards, Simon - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Expressions, Collections, Filtering oh my..
Here are two ways to do this, JXPath is easier as you won't have to
write your own Predicate.
Say you have a collection of Person objects that you created with this code:
Person person1 = new Person();
person1.setName( Bill );
person1.setAge( 12 );
Person person2 = new Person();
person2.setName( Amy );
person2.setAge( 18 );
Person person3 = new Person();
person3.setName( Doug );
person3.setAge( 25 );
List personList =
Arrays.asList( new Person[] { person1, person2, person3 } );
You can filter this collection using JXPath and an XPath expression that
references the age property AS IF it were an XML attribute:
JXPathContext context = JXPathContext.newContext( personList );
Iterator iterator = context.iterate([EMAIL PROTECTED] = 18]);
while( iterator.hasNext() ) {
Object o = (Object) iterator.next();
System.out.println( Person: + ((Person) o).getName());
}
Or, you can write a custom JexlPredicate that takes an expression and
evaluates each element in a Collection. Here's code that filters a
collection of Person beans and returns only those instances that have an
age = 18:
Predicate predicate = new JexlPredicate( object, object.age =
18 );
Collection canVote = CollectionUtils.select( personList, predicate );
for( Object o : canVote ) {
System.out.println( Person: + ((Person) o).getName() );
}
The JexlPredicate from this example would be the following class:
JexlPredicate.java
import org.apache.commons.collections.Predicate;
import org.apache.commons.jexl.Expression;
import org.apache.commons.jexl.ExpressionFactory;
import org.apache.commons.jexl.JexlContext;
import org.apache.commons.jexl.JexlHelper;
public class JexlPredicate implements Predicate {
private String variable;
private Expression e;
public JexlPredicate(String variable, String expression) {
this.variable = variable;
try {
this.e = ExpressionFactory.createExpression(expression);
} catch (Exception e) {
throw new RuntimeException(Error creating JEXL expression, e);
}
}
public boolean evaluate(Object o) {
JexlContext jc = JexlHelper.createContext();
jc.getVars().put(variable, o);
Boolean b;
try {
b = (Boolean) e.evaluate(jc);
} catch (Exception e) {
throw new RuntimeException(Error evaluating JEXL
expression, e);
}
return b.booleanValue();
}
}
/JexlPredicate.java
Poppe, Troy wrote:
I've got a collection of a JavaBeans, it could be a plain-old-Java collection or
a Commons-Collection... Not really a concern...
I'm trying to find a way to provide the ability to write a JEXL-like expression
that would be applied against the collection of JavaBeans, and be able to
retrieve all of the JavaBeans that match that JEXL-like expression.
So far, looking at JEXL, it looks like it requires a JexlContext, but I don't
see
or know how I would adapt my JavaBean properties to this.
Is there an out-of-the-binary way of filtering through my JavaBeans, and giving
me access to those that match some expression?
Thanks.
Troy
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Re: [CLI] two different versions of commons-cli-1.0.jar?
On Tue, 2005-07-05 at 23:43 +0200, Hansine Jensen wrote: When you download from http://jakarta.apache.org/site/downloads/downloads_commons-cli.cgi you get cli-1.0.zip which is the original distribution from November 2002 containing commons-cli-1.0.jar corresponding to http://svn.apache.org/repos/asf/jakarta/commons/proper/cli/tags/CLI_1_0/ But if you download http://www.ibiblio.org/maven/commons-cli/jars/commons-cli-1.0.jar or e.g. http://apache.usp.br/java-repository/commons-cli/jars/commons-cli-1.0.jar you get a different archive containg two more classes, OptionValidator and Util. This versions seems to be the one described at http://jakarta.apache.org/commons/cli/apidocs/org/apache/commons/cli/package-summary.html also claiming to be Commons CLI 1.0. Can someone please explain what is going on here? I can confirm the above info is correct. It sure looks like a cock-up to me. It would appear that after the 1.0 release no-one updated the currentVersion tag in project.xml and that at some later time someone compiled the trunk code and published it on ibiblio as commons-cli-1.0 when it was actually a snapshot of trunk. I wonder if there is a tag in svn for the maven version or if it is a snapshot of http://svn.apache.org/repos/asf/jakarta/commons/proper/cli/trunk/ It sure looks to me like the version on ibiblio (which Maven will download) is a snapshot of some unknown state of trunk. The file on ibiblio is dated 29 jan 2004 so I guess that's the date that the code is from. The version# in project.xml was updated on 22 april 2004, so the snapshot is certainly before that date. I think the best thing to do would be to publish a cli-1.0.1 which is identical to 1.0, ie copy tags/CLI_1_0 to CLI_1_0_1 then update the version# and build a new release. The 1.0 release on ibiblio should then be deleted. Yes this will break a whole bunch of existing projects that depend on 1.0 - but I can't see any better way out of this. Is there anyone from the CLI team willing to do this? NB: This problem isn't anything to do with Maven. Regards, Simon - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
