| Roedy 's convertor, Where is Short ? Where is Byte? |
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- 8
- generate certificate from PEMHi,
I am developing a middleware solution for our companyy. I have got 2
certifcates clkey.pem and clcert.pem for the final application. How I
can combine these 2 keys in 1 certificate? Do I need to first create
self signed certificate?
Thx in advance.
- 8
- LookAndFeelHi,
I have a couple of issues I'm trying to resolve. Hopefully someone will have
some ideas.
First, I've been unsucessful trying to get the MotifLookAndFeel working.
I've following every example I have (on paper) and nothing seems to work.
I've run the app on both the PC and Linux box; the window looks and feel
shows up on the PC and metal on the linux machine. Anyone know what's going
on or what could be missing?
Second, the app I've been working has a bunch of ToggleButtons and the color
of the button changes based on selection. All I do is set the background
color in the button press callback. Okay, fine. But when I run the code in
linux, I'm unable to change the color of the "select" mode of the Toggle
button. It always gray. Again. Does anyone know what's going on? From all my
years, this should be extremely simple. Why would it work correctly on the
PC and not in unix?
Thanks in advance.
Bryan
- 9
- javax and macim running mac os 9.2 with MRJ SDK 2.2. im tring to compile a class
importing javax.swing.*; it says it cant find it. i unziped all the
jars and i cant find javax anywhere. is this not supported on this os.
- 10
- Running server-side Java on FreeBSD in production environments
So, I've seen a few mentions here of folks using Java server apps on
FreeBSD in production. I've been very happy to watch the progress by the
Java team on the native JDKs from the sidelines, as well as the
improvements to libc_r and such that have been MFC'd, but I'm curious as
to whether the consensus on this list is that it's ready to be used for
production. Anyone want to share good success or horror stories? We're
trying to determine whether the apache.org box can start to run our own
software. :) Speed is definitely less important than proper functioning.
Brian
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- 10
- getting Error: could not find libjava.so Re: building a jdk1.5
On Mar 3, 2007, at 5:18 PM, Bill Moran wrote:
>
>> On Mar 3, 2007, at 4:01 PM, Chad Leigh -- Shire.Net LLC wrote:
>>
>>> Hi
>>>
>>> I am trying to build jdk15 inside my jail with PREFIX set to /usr/
>>> public (At one time I successfully got jdk 1.4 to build after much
>>> hacking)
>>>
>>> I have the option for builing inside a jail set. We get to the
>>> point where the linux java is installed and it is actually building
>>> the jdk
>>>
>>> # Start of jdk build
>>> /libexec/ld-elf.so.1: /usr/local/lib/libiconv.so.3: Undefined
>>> symbol "__mb_cur_max"
>>> *** Error code 1
>>>
>>> Stop in /usr/ports/java/jdk15.
>>> #
>>>
>>> I am not exactly sure what it is doing at this point in order to
>>> hack round it. libiconv a fresh install from ports
>>>
>>
>> Turns out that the issue is that gmake cannot run. I have not
>> figured out why yet, having removed and reinstalled libiconv and
>> gmake and getting the same error. But it is not java related.
>>
>> I'll redirect this to -questions
>>
>> If anyone has an idea on why gmake would fail as above on a fresh
>> install, 6.2-RELEASE from a day or two ago, I would appreciate it.
>> Please CC me as I am not currently subscribed to -questions, though I
>> am on -java
>
> Not a direct answer to your question, but when I needed to do this
> a few months ago, I just did a "make package" on my workstation, then
> shipped the package up to the jail system and installed it with
> pkg_add.
>
> Doesn't solve the problem, but if you're in a pinch, it's a handy
> workaround.
>
OK, I had never done this before -- built a package from a port. So
I did this on the base machine and then copied it into the jail and
did a pkg_add like so
# pkg_add -P /usr/public -v jdk-1.5.0p4_1.tbz
as I wanted it installed in my local policy dir /usr/public (which
gets mounted RO in every jail). My 1.4.2 java on my other jail
server is installed like this (but was built inside the jail many
moons ago).
Now, when I try to run java I get
# java -version
Error: could not find libjava.so
Error: could not find Java 2 Runtime Environment.
#
Java is in /usr/public/jdk1.5.0/ (the same as my 1.4.2 on the other
server which is in /usr/public/jdk1.4.2/). libjava.so is inside the
lib dir and I thought that java was referential to itself so it could
find its libraries.
I also tried setting JAVA_HOME and JRE_HOME though I have not had to
do that in a long time.
The new 1.5 jdk is registered in the javavms file .
When I run the javavm script with /bin/sh -x it does run the correct
java and running it with an explicit path does not help.
# /bin/sh -x /usr/public/bin/javavm -version
+ _JAVAVM_SAVE_PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/games:/usr/pub/
sbin:/usr/pub/bin:/usr/local/sbin:/usr/local/bin:/usr/X11R6/bin:/root/
bin
+ export PATH=/bin:/sbin:/usr/bin:/usr/sbin
+ _JAVAVM_PREFIX=/usr/public
+ _JAVAVM_CONF=/usr/public/etc/javavms
+ _JAVAVM_OPTS_CONF=/usr/public/etc/javavm_opts.conf
+ basename /usr/public/bin/javavm
+ _JAVAVM_PROG=javavm
+ _JAVAVM_MAKE=/usr/bin/make
+ [ javavm = javavm ]
+ echo javavm: warning: The use of 'javavm' as a synonym for 'java'
is deprecated
javavm: warning: The use of 'javavm' as a synonym for 'java' is
deprecated
+ _JAVAVM_PROG=java
+ [ -r /usr/public/etc/javavm_opts.conf ]
+ . /usr/public/etc/javavm_opts.conf
+ _JAVAVM_OPTS=
+ setJavaHome
+ realpath
+ realpath /usr/public
+ [ -n -a /stubs/usr_local/etc/ssmtp != /usr/public ]
+ unset JAVA_HOME
+ _JAVAVM_PORTSDIR=
+ [ -r /usr/share/mk/bsd.port.mk ]
+ /usr/bin/make -f /usr/share/mk/bsd.port.mk -V PORTSDIR
+ _JAVAVM_PORTSDIR=
+ _JAVAVM_BSD_PORT_MK=
+ [ -n -a -r /Mk/bsd.port.mk ]
+ [ -n ]
+ [ ! -e /usr/public/etc/javavms ]
+ sed -E s|[[:space:]]*#.*||
+ uniq
+ _JAVAVM_VMS=/usr/public/jdk1.5.0/bin/java
/usr/public/linux-sun-jdk1.4.2/bin/java
+ [ -n ]
+ dirname /usr/public/jdk1.5.0/bin/java
+ JAVA_HOME=/usr/public/jdk1.5.0/bin
+ dirname /usr/public/jdk1.5.0/bin
+ JAVA_HOME=/usr/public/jdk1.5.0
+ basename /usr/public/jdk1.5.0
+ _JAVAVM_VM=jdk1.5.0
+ [ -n ]
+ [ -n ]
+ [ -n ]
+ [ -n /usr/public/jdk1.5.0 -a -f /usr/public/jdk1.5.0/bin/java ]
+ _JAVAVM_PROG_PATH=/usr/public/jdk1.5.0/bin
+ return 0
+ [ 0 != 0 ]
+ [ -x /usr/public/jdk1.5.0/bin/java ]
+ basename /usr/public/jdk1.5.0
+ setJavaOptions java jdk1.5.0
+ echo java
+ sed -e s/\./_/g -e s/-/_/g
+ local OPTS_PROG=java
+ echo jdk1.5.0
+ sed -e s/\./_/g -e s/-/_/g
+ local OPTS_JAVA_HOME=jdk1_5_0
+ eval echo ${JAVAVM_OPTS_jdk1_5_0_java}
+ local JAVA_HOME_PROG_OPTS=
+ eval echo ${JAVAVM_OPTS_jdk1_5_0}
+ local JAVA_HOME_OPTS=
+ eval echo ${JAVAVM_OPTS_java}
+ local PROG_OPTS=
+ [ -n ]
+ [ -n ]
+ [ -n ]
+ [ -n ]
+ export JAVA_HOME
+ tryJavaCommand /usr/public/jdk1.5.0/bin/java -version
+ [ -n ]
+ [ -x /usr/public/jdk1.5.0/bin/java ]
+ [ -n /sbin:/bin:/usr/sbin:/usr/bin:/usr/games:/usr/pub/sbin:/usr/
pub/bin:/usr/local/sbin:/usr/local/bin:/usr/X11R6/bin:/root/bin ]
+ export PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/games:/usr/pub/sbin:/
usr/pub/bin:/usr/local/sbin:/usr/local/bin:/usr/X11R6/bin:/root/bin
+ exec /usr/public/jdk1.5.0/bin/java -version
Error: could not find libjava.so
Error: could not find Java 2 Runtime Environment.
#
What did I do wrong?
Thanks
Chad
---
Chad Leigh -- Shire.Net LLC
Your Web App and Email hosting provider
chad at shire.net
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- 10
- Great SWT ProgramIn article <email***@***.com>,
Twisted <email***@***.com> wrote:
> On Aug 21, 1:30 pm, Joe Attacki <email***@***.com> wrote:
> [Attacki misattributed the quoted text once again]
> [insulting nonsense deleted]
> > Honestly, I don't care if he advertises his open-source project in here,
> > but the fact that he was underhanded about it is what I took issue with.
>
> I've provided a reasonably plausible and much more charitable
> interpretation of his actions. You are quick to see malice where there
> may well be none;
Oh, the irony.
> probably because your own normal behavior is
> malicious, so you expect it of everyone else as your default model for
> a random person's mind is (as is normal) your self-model.
--
B. L. Massingill
ObDisclaimer: I don't speak for my employers; they return the favor.
- 10
- M.I'5.Persecut ion ` h ow a nd wh y d id it st art?-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-= how. and why did it start? -=
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
The harassment didn't start by itself, so someone. must have been there at
the outset to give it a firm push and set the "animals" after me. It. looks
as if I was. set up in June 1990, and the timing indicates someone from
university. was responsible.
>One thing which has. been missing from this discussion is this simple
>prognosis: that maybe he is. right and that, despite his admitted
>mental condition, there really is a campaign against. him organised by
>now-influential ex-students of. his university.
In May or June 1990, Alan Freeman on Radio 1 read out a letter from. someone
who had known me for a few years, who. wrote of the one who "wore out his
welcome with random precision" (from the Pink Floyd. song). Freeman went on
to say to the writer "that's a hell of a letter. you wrote there". The
indication is strongly that. people I had parted from soon before nursed a
grudge against me and were trying to. cause trouble for me.
The suggestion is that Freeman might have shown the letter. to other people,
and things could. have snowballed from there. Right from the start the real
source (security services presumed). didn't announce themselves as the
origin,. but let the "talkers", the radio DJs, believe that they were the
originators. Think about it; if you. announce, "we're MI5 and we have a
campaign against this bloke" then people might not go along. with it; but if
you say, "everyone else. is getting at this bloke because he 'deserves' it"
then people. will join in with fewer qualms.
>Why. would "they" wish to assassinate your character?
It's the classic case of hitting a cripple to prove you're. stronger. Why
would the security services expend hundreds of. thousands of pounds and more
than six years of manpower to try to kill a British citizen? Because. they
are motivated by people who knew me at. university and feel personal
animosity; because they knew me to be emotionally weak, and it is. in the
nature of bullies to prey on those known. to be weak; and because they can
rely on the complicity of the establishment, which the. security services
manipulate and derive funding from. This is. England's biggest humiliation
today,. and the British security services are intent on preventing their
humiliation becoming reality by. continuing their campaign of attempted
murder to suppress the. truth from becoming public.
10751
- 12
- J2ME internationalizationI want to provide the binary with *only one* language, because I want to
be as small as I can.
But I want to provide many binaries (one per language).
So, I write the code with hardcoded strings like "$_nearest_dist_$".
I write a file like:
-----english.ini----
$_nearest_dist_$=Nearest distance is 90m
--------------------
and I write a php script which in *.java files, replaces all strings in
form "$_*_$" with language correct string.
php phpWriteStringsToSource.php <project_folder> <language.ini>
THE BIG PROBLEM: I realize that *.java files must have ansi* encoding!
Any of utf-8, uc16le or be is not compiled correct!
So, what I can do?
- 13
- Initialize managed bean with header information?We use Netegrity's SiteMinder for SSO security on all web apps.
Although SiteMinder handles security for accessing the application
itself, restrictions to certain functions and data are handled within
the application based on user type.
The user information (such as name, type, etc.) are passed in from
SiteMinder via header variables. ie:
hddr_user = Joe Blo
hddr_group = Admin
hddr_phone = 555-555-5555
I'm looking at different designs to capture all of this user
information from the headers at one time and store as a bean in the
user's session (so as to not need to continually reference the header
information).
Does anyone know if you can create a managed bean (ie. User) that is
initialized with header information (by using the configuration file
w/ value-binding expressions)?
- 14
- Help to understand 'array of classes' exampleHi,
I'm trying to create/use an array of classes, and I found the following
code snippet using Google Groups:
...
rectangle[ ] array_name = new rectangle[ 100 ]; // or whatever
size
for ( int n = 0; n < 100; ++n )
{
array_name[ n ] = new rectangle( );
}
...
int i = 99;
int wide = array_name[i].getwidth( );
...
The above snippet was from:
http://groups.google.com/group/comp.lang.java.programmer/msg/1ea4bbde51104914
What I'm trying to understand in the above snippet is the line where the
array is initialized:
rectangle[ ] array_name = new rectangle[ 100 ]; // or whatever size
Before I found that post, I was trying something like:
rectangle [] arrayName; // declear an array of 'rectangle classes'
.
.
rectangle[0] = new rectangle(); // instantiate rectangle/populate array
rectangle[1] = new rectangle(); // instantiate rectangle/populate array
I did it that way because I don't know the number of classes that I'll
want to have in the array of classes ahead of time.
The code per the snippet from the cited posts works, but my original
code would get a NullPointerException, and I don't understand why.
Can someone explain this?
Also, is it possible to do this in a way that I don't have to allocate a
fixed size array?
Thanks,
Jim
- 14
- How do i implement this interfacepublic interface AQuestion
{
public abstract void someMethod() throws Exception;
}
http://www.angelfire.com/or/abhilash/Main.html
see Question no 5.
How do i implement this interface ?
(1) problem is, it has an abstract method and hecne its complicated
to implement this class.
(2) another problem is, it is the public interface and hence we can not
make one more public class in the same file....because 1 file can have
only 1 public access specifier.
is it really possible to implement this interface ?
- 14
- JTable and Custom Default Cell Editors
From: "Erica Wheatcroft" <email***@***.com>
Subject: JTable
Date: Thursday, January 20, 2005 4:17 PM
HI -
I have a jtable that uses two custom default cell editors to create combo
boxes for two of the the 4 columns. If the user selects another value from
either of the combo boxes i want to know that so i can indicate a save must
occur. I'm not sure what event i should listen to? Does any one have any
suggestions?
Thanks in advance.
Erica
- 14
- passing RequestPath to error page from web.xmlHi,
I have pointed any errors to Error.jsp in my web.xml file (as shown).
<error-page>
<error-code>500</error-code>
<location>/Error.jsp?id=500</location>
</error-page>
As you can see I also pass the type of error, is there any way I can
pass the RequestPath that resulted in the error in the first place?
Cheers,
Paul
- 14
- Tomcat on Windows: JAVA_HOME & -Dsun.io.useCanonCaches'Apologies for posting this here, but I couldn't find any Tomcat user
forum.
A colleague is currently trying to run Tomcat 4.1.30 on Windows 2000
Professional. She first installed JRE2 1.4.2_08, and set %JAVA_HOME%
to the directory C:\j2re1.4.2_08 - I've run "java -version" and it
works fine.
(%JAVA_HOME%/home is in the path correctly).
She then installed Tomcat to C:\jakarta-tomcat-4.1.30.
However, when she runs catalina.sh start, she gets the following
error:
The JAVA_HOME environment variable is not defined correctly
This environment variable is needed to run this program
Using CATALINA_BASE: C:\jakarta-tomcat-4.1.30
Using CATALINA_HOME: C:\jakarta-tomcat-4.1.30
Using CATALINA_TMPDIR: C:\jakarta-tomcat-4.1.30\temp
Using JAVA_HOME: C:\j2re1.4.2_08
'-Dsun.io.useCanonCaches' is not recognized as an internal or external
command,
operable program or batch file.
I've even tried adding the following to catalina.bat without success:
if not "%JAVA_HOME%" == "" goto gotJavaHome
set JAVA_HOME=C:\j2re1.4.2_08
:gotJavaHome
Can anyone see where we might be going wrong?
Cheers,
P.
- 15
- TableCellRender puzzleBelow is a fairly simple TableCellRenderer for displaying an enum as
an Icon. That works fine. But I added a wrinkle, changing the
background colour depending on whether the row is selected.
No background colour changes happen, even though isSelected is true
when it should be. I wonder if I am missing something obvious.
package com.mindprod.vercheck;
import javax.swing.*;
import javax.swing.table.TableCellRenderer;
import java.awt.*;
/**
* render a the AppSate enum cell, use icon without text.
*/
final class AppStateRenderer implements TableCellRenderer
{
// ------------------------------ FIELDS
------------------------------
private static final JLabel template = new JLabel( "",
JLabel.CENTER );
private Color background;
private Color selectedBackground;
// -------------------------- PUBLIC INSTANCE METHODS
--------------------------
/**
* constructor
*
* @param background background colour
* @param selectedBackground background colour when seleced
*/
public AppStateRenderer( Color background, Color
selectedBackground )
{
this.background = background;
this.selectedBackground = selectedBackground;
}
public Component getTableCellRendererComponent( JTable table,
Object value,
boolean
isSelected,
boolean hasFocus,
int row,
int column )
{
System.err.println( "selected:" + isSelected + " " + row + " "
+ table.getSelectedRow() );
template.setIcon( ( (AppState) value ).getIcon() );
template.setBackground( isSelected? selectedBackground :
background );
return template;
}
}
--
Roedy Green, Canadian Mind Products
The Java Glossary, http://mindprod.com
|
| Author |
Message |
mphelps
|
 Posted: 2003-11-18 10:52:00 |
Top |
java-programmer, Roedy 's convertor, Where is Short ? Where is Byte?
Hi Roedy,
This is what you advertise for in
http://www.mindprod.com/zips/java/converter.txt:
signed byte Byte
unsigned byte Byte
short Short
char Character
int Integer
long Long
float Float
double Double
char[] String
This is what you have in your code:
public static final String [] flavours = {
"boolean",
"/*signed*/ byte",
"/*unsigned*/ byte",
"short",
"char",
"int",
"long",
"float",
"double",
"String",
"Boolean",
"Character",
"Integer",
"Long",
"Float",
"Double"};
Noticed anything? Is it voluntary or did you forget java.lang.Byte
and java.lang.Short?
Either the advertisement or the code need to be updated.
My apologies if you have already explained why.
BTW, neat little tool I always come back from time to time.
Cheers, Mike
|
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Index ‹ java-programmer |
- Next
- 1
- Java rendering problems when antialiasing is enabledI've written a Java app which uses Swing to display images and text.
The app consists of a JFrame which contains a JPanel-derived class. In
the paint() method of the JPanel-derived class, I call
Graphics.drawImage() to render an image file previously loaded with
ImageIO.read().
This was working fine until I enabled antialiasing in my video card
settings (GeForce FX 5200 w/128MB RAM, Windows XP SP2). With
antialiasing, none of the content gets rendered in the window. The
problem exhibits itself when I'm tring to render the image myself and
when I just have a JProgressBar control displayed in the window (i.e.
the Swing components themselves aren't correctly rendering with
antialiasing turned on either).
I've received feedback from multiple users seeing this issue as well,
so its not just my machine.
Any ideas? Disabling antialiasing fixes the problem, but I'd like to
be able to get my app to work regardless of whether antialiasing is
enabled/disabled.
- 2
- [ANN] RMI Plug-in for Eclipse v2.0A new version of the RMI Plug-in for Eclipse (v2.0) has been just released.
In the new version there are two new major features:
(*) RMI Spy - Live monitor of the RMI activity in an RMI application
(*) Ready to use examples - the best way of getting started with RMI in
Eclipse
The RMI Registry inspector has greatly improved and it can now invoke
almost any remote method (in previous version it was only possible to
invoke methods that receive no arguments).
Also new in v2.0 - enhanced Java 5 and Java 6 support.
The standard set of features includes
(*) Automatic stubs genaration
(*) Local RMI registry control (start/stop/clean)
(*) RMI Application Launcher - easy codebase and security policy
configuration.
More info at: http://www.genady.net/rmi/v20/
Genady Beryozkin,
Author of the RMI Plug-in for Eclipse
- 3
- jEdit JavaDebuggerDoes anyone know how to set this plug-in up? I have loaded it in jEdit
but everytime I try and use it it gives a huge long error list and says
I need JDK 1.3 or above, even though I am using JDK 1.5!
Steve
- 4
- Is JAR signing _ever_ harmful?I'm having a series of ructions with our on-site installation people,
re: JAR signing. It's a big app, big budget, and we have lots of
be-suited consultants running around on customer sites for long
periods. I live back in the coder's garret, making the product.
Sometimes they throw me the odd doughnut.
Basically they're reporting every bug and misconfiguration they can
find as being caused by our recent switch to JARs rather than loose
.class files, and in particular by these JARs being signed. It's a
self-generated key, without an X509 cert (at present).
Before I go postal with the +3 Lart-o-doom, can I please ask if there
are _ANY_ circumstances, no matter how perverse, where signing a JAR
could cause something to break? I know of nothing. Nada. Zilch.
One problem we have had was due to signing across two JARs having been
done by different keys. As the real problem here was trying to mix code
from product versions V1 and V2 (a big non-no anyway) then I see this
more as a feature than a bug. But try telling them that...
- 5
- Tiles Problem with definitions Error - Tag InsertHi to all,
I have a newbie problem and I would appreciate any help.
Thanks in advance.
I have the following constellation:
struts-config.xml:
<snip >
<plug-in className= "org.apache.struts.tiles.TilesPlugin " >
<set-property property= "definitions-config "
value= "/WEB-INF/tiles-defs.xml " / >
<set-property property= "moduleAware " value= "true " / >
<set-property property= "definitions-parser-validate " value= "true "
/ >
</plug-in >
<snap >
tiles-defs.xml
<snip >
<tiles-definitions>
<definition name="definitionName" page="/layouts/layout1.jsp">
<put name="title" value="to be specified" />
<put name="header" value="/tiles/header.jsp" />
<put name="footer" value="/tiles/footer.jsp" />
<pat name="body" value="to be specified" />
</definition>
</tiles-definitions>
<snap >
All referenced JSP exist in the webapp!
Additionally I have a JSP index.jsp that looks like this:
<snip >
<tiles:insert beanName="definitionName"/>
<snap >
There are no action-mappings in the struts-config.xml!
When I call the index.jsp I receive the following error:
org.apache.jasper.JasperException: Error - Tag Insert : No value
defined for bean 'definitionName' with property 'null' in scope
'null'.
I know, that means that there is no bean with this name in any
context.
I check this with <logic:notPresent name="definitionName"
scope="application">
But I have read that the in the case i figured out, all definitions in
tiles-defs.xml are available in the application context under their
"name" attribute. But it seems that I'm wrong.
Does anyone know what goes wrong here. Or do I have to use
action-mappings to work with xml-based definitions?
Greetings
Stephan
- 6
- How to set size for JComboBoxHi all,
I am developing an application, which will have two JComboBoxes and
two JTables, and i am using gridbag layout.
when the initial string for JComboBox is small enough then these
sets(JComboBox and JTable) are divided equally, when the initially
string is big then the two sets(JComboBox and JTable) are not divided
equally, how can i divide them equally irrespective of the string
length.
I used the setSize(),setPreferredSize(),and setMaximumSize() for
JComboBox but there is no result ,
Plz help me,
Thanks in advance
dwurity
- 7
- where to find graphics for buttonsI'm searching for free graphics to grade up my app by using icons on the
buttons for edit, new, delete, save, cancel and so on.
Java class ImageIcons supports gif, jpeg and png format.
Anybody knows a free available source for this basic app icons?
- 8
- To really foul things up requires a computerPartner just got back from a new government job with an amusing tale.
BC is a large province (about 1000 miles top to bottom) so the BC
government decided to set up a computer system so that any printout
could be directed to any printer in the province, thus saving on
courier costs.
However, the default is the system selects a non-busy printer, not
worrying particularly if it is 1000 miles from the intended recipient.
The printouts don't have proper headers to direct them to the person
eagerly awaiting them so most of the printouts ended up in the
shredder.
- 9
- Any goodhearted person willing to explain me a program in Java I gotHello
What I'll will ask may take some of your time.
I have no experience at all with Java. But I could get my hand on a
programme written in Java, which does exactly what I want.
But I'm eager to learn, and want to know how it does everything.
I'm not interested in the visual aspect but in the communication
What the program does is communicate with a little box, that catches
data from a machine.
In essence it replaces a printer.
The machines prints to a usb port, via a adaptor, the printing data
goes into a little box, and then via a usb connection goes to the
reading pc.
I want to understand that.
Does anyone has some spare time for this (and "teaching skills") ?
I have the jar's and the classes (decompiled also)
For the moment I will not post the sources online.
Many thanks in advance and have a nice day
- 10
- Set jtable cell coloursHi,
How do i change the colour of a cell in a Jtable, looked at api but couldnt
find anything.
Thanks
Rudy
- 11
- Array optimizing problem in C++?
From an old post by James Kanze
On Apr 9 2003, 5:42 pm, email***@***.com (James Kanze) wrote:
>When I pass an "array" to a function in C/C++, I actually pass
>a pointer to the first element. And the compiler, when it compiles the
>function, only sees pointers -- it has no way of determining any
>relationship between them. Consider, for example, a smoothing function
>(in C or earlier C++):
>
> void
> smooth( double* dest,
> double const* src,
> size_t len )
> {
> for ( size_t i = 1 ; i < len - 1 ; ++ i ) {
> dest[ i - 1 ] = (src[ i - 1 ] + src[ i ] + src[ i + 1 ]) / 3 ;
> }
> }
>
>
>The compiler cannot arrange to use the src[ i + 1 ] value from the
>preceding pass through the loop as the src[ i ] value in the current
>pass, since the write to dest[ i - 1 ] might have changed it. In Java,
>it can, since two arrays are either identical or disjoint.
>
>
>This sort of code shows up frequently. In benchmarks from Java
>suppliers comparing Java to C++, of course:-). But also in any number
>of applications dealing with physical measures: meteorology, geophysical
>research (oil prospection), etc.
Out of curiosity, I tried to test if the above is true. It didn't make
any difference. In fact, C++ was a bit faster (not by much, just 6%).
Probably due to array bound check in Java, if there is in indeed an
issue with C++ arrays, overall there is no difference.
==c++==
#include <iostream>
#include <cstdlib>
#include <ctime>
void fill (double* src, int len);
void smooth (double* dest,
double const* src,
int len );
int main()
{
const int len = 50000;
double src_array [len] = {0};
double dest_array [len] = {0};
fill(src_array, len);
clock_t start=clock();
for (int i = 0; i < 10000; i++)
smooth (dest_array, src_array, len);
clock_t endt=clock();
std::cout <<"Time smooth(): " <<
double(endt-start)/CLOCKS_PER_SEC * 1000 << " ms\n";
// doesn't work without the following cout on vc++
std::cout << dest_array [0] ;
return 0;
}
void smooth (double* dest, double const* src, int len )
{
for (int i = 1 ; i < len - 1 ; i++ ) {
dest[ i - 1 ] = (src[ i - 1 ] + src[ i ] + src[ i + 1 ]) / 3 ;
}
}
void fill (double* src, int len)
{
srand((unsigned)std::time(0));
for (int i = 0 ; i < len ; ++ i ) {
src[i] = rand();
}
}
==== java ========
import java.util.*;
public class Arrays{
public static void main (String[] arg)
{
final int LEN = 50000;
double[] src_array = new double [LEN];
fill(src_array, LEN);
double[] dest_array = new double [LEN];
long start = System.currentTimeMillis();
for (int i = 0; i < 10000; i++)
smooth(dest_array, src_array, LEN);
long end = System.currentTimeMillis();
System.out.println("Time smooth(): " + (end - start) + " ms");
}
static void smooth (double[] dest, double[] src, int len )
{
for (int i = 1 ; i < len - 1 ; i++ ) {
dest[ i - 1 ] = (src[ i - 1 ] + src[ i ] + src[ i + 1 ]) / 3 ;
}
}
static void fill (double[] src, int len)
{
for (int i = 0 ; i < len; i++)
src[i] = Math.random();
}
}
- 12
- Eclipse and Tomcat DevelopmentHi,
I am trying to figure out how to change the build path for my java servlets
in eclipse so that my class files are located within my Apache Tomcat
servers class directory. I tried to change the output folder in eclipse for
the project properties but it doesn't seem to accept it as a valid
directory. It only accepts folders with the current projects working
directory (ex. eclipse\workspace\myProject). Any idea how to do this without
the use of plugin's. If not can someone recommend me the most popular plugin
to get this job done. Thanx in advance
Joe
- 13
- RegEx !compileHi,
I am using Eclipse, Java SDK 1.4 and the java.uitl.regex
I am trying to using regular expressions in my code
I could write something simple like:
String re = "\d";
And I am receiving an invalid escape sequence error.
And I am not so sure why
Aidy
- 14
- netbeans uml pluginhi,
does anyone know if there is a plugin that will create uml diagrams from my
java code for the netbeans ide? i have looked on their website and they say
to use poseidon, but i have not really been able to integrate it into my
netbeans ide.
thanks
Jochen Opp
- 15
- DOM Partial Document ParsingI am trying to build a Java client which will read a never ending XML
data stream from a socket. Here is a simplified example of the XML
document:
<?xml version='1.0' encoding='us-ascii'?>
<NeverendingDataStream>
<Data>1.0</Data>
<Data>2.0</Data>
followed by a continuous stream of <Data> elements from a server
application that may not send the closing </NeverendingDataStream> tag
for several hours or days.
The DocumentBuilderFactory and DocumentBuilder parser for building a
DOM object tree fails because of a missing end tag.
Is there a way to force partial document parsing? I have turned
validating off but it continues to throw a fatal error.
Thanks,
Gary V
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