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- 1
- Binomial Simulation-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
I'm taking a class in Evolutionary Computation. I just turned in an
assignment that implements a simple genetic algorithm based on bit
strings. For mutation I simply check each bit in the population and
flip it with some constant probability. For a population of 10,000
individuals of 100 bits that means that I have to execute the method
Random.nextDouble() 1,000,000 times. I thought about this a bit and I
could do the same operation by getting a single value from a binomial
distribution and then selecting that number of bits at random. This
would require far fewer operations that the current brute force method.
For real problems this might not matter that much since mutation would
take a small percentage of the time spent in the algorithm, but for my
test problems mutation is the biggest contributor to run time.
So, now to the question. Is there an open source implementation of
nextBinomial() out there somewhere? I did a quick search of the web and
didn't find one. I could implement my own, but it probably wouldn't be
as fast as a widely used open source implementation and I don't want to
spend the time on something that is really a library function if I don't
have to.
Note that I'm not trying to cheat here. If I end up using it in an
assignment I will credit the author and the prof won't mind. This is a
graduate course.
Thank you.
- --
Kenneth P. Turvey <email***@***.com>
http://kt.squeakydolphin.com (not much there yet)
Jabber IM: email***@***.com
Phone: (314) 255-2199
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- 1
- implicit <? super T> when an array is a parameter in a generic methodi'm making some adjustments to previous code to utilize generics in java
1.5 or 5.0 or whatever it is called. something seems inconsistent,
though:
let us say i have a method that operates on two collections:
public <T> void testMethod(Collection<T> c1, Collection<T> c2){...}
if i call this method with the following line, a compile-time error
occurs:
testMethod(new HashSet<Integer>(), new HashSet<Number>());
and rightly so. in this case T != T (i.e. Integer != Number).
the method would have to be rewritten to:
public <T> void testMethod(Collection<T> c1, Collection<? super T>
c2){...}
and this indeed works. this is fine and quite logical.
now the problem. let us assume i have a method that copies elements
from an array into a collection:
public <T> void testMethod(T[] a, Collection<T> c){...}
suddenly i'm allowed to call this method with T != T, as in:
testMethod(new Integer[100], new HashSet<Number>());
the official word from sun is: "it will generally infer the most
specific type argument that will make the call type-correct." apparently this
line is only in reference to arrays (although they don't mention that).
so when this "inferring" occurs, is there basically a re-writing going
on the background that equates to changing the function to:
public <T> void testMethod(T[] a, Collection<? super T> c){...}
?
i guess the true root of the question is, which of the parameters (and
indeed there may be many) will be going through the inferring process?
there must be at least one "baseline" argument type parameter in calls
like these that remains fixed (i.e. cannot go through an inferring
process), because otherwise every type argument could just be inferred to be
Object, making all calls legit and ruining the advantage of generics.
wow, that may have been a bit confusing, but if anyone would point me to
a general good source on java's version of generics (not sun's
documents, as i've already tried to read those and they don't clear up this
confusion at all), it would be greatly appreciated.
thanks,
murat
- 1
- Getting value of variable from Thread to main classI have a problem, with getting value of a variable that is set in
thread. I start the Thread in a main class, thread gets the value from
server and sets it as static variable. After starting the thread I try
to print the value of " threadObjetc.staticvariable " but every time
it has a null value. I suppose that the reason for that is that thread
works in a background and functions of main class continues anyway. If
someone had a similar problem and could help me to avoid it I would be
gratefull for help, Thanks
- 1
- SwingUtilities.getRoot() in a javax.swing.ActionAfter reading
http://www.exampledepot.com/egs/javax.swing/frame_FrameFind.html
I wrote a small test program in which I found that
SwingUtilities.getRoot() returns null. getRoot() works well for me in
other programs when I feed it a container (e.g. JPanel).
What am I doing wrong? Cannot SwingUtilities trace the JFrame to which
the JMenuItems are ultimately attached? Why not?
------------------------------------8<-------------------------------
import java.awt.Component;
import java.awt.event.ActionEvent;
import javax.swing.*;
public class EnumAction {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new EnumAction();
}
});
}
EnumAction() {
JMenu m = new JMenu("Menu");
for (Command c : Command.values())
m.add(new JMenuItem(c.action));
JMenuBar mb = new JMenuBar();
mb.add(m);
JPanel p = new JPanel();
p.add(new JLabel("EnumAction"));
JFrame f = new JFrame("EnumAction");
f.setJMenuBar(mb);
f.add(p);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setVisible(true);
}
}
enum Command {
CMD_THIS("This"), CMD_THAT("That");
Action action;
Command(final String label) {
action = new AbstractAction() {
{
putValue(Action.ACTION_COMMAND_KEY, name());
putValue(Action.NAME, label);
}
public void actionPerformed(ActionEvent event) {
System.out.println(event.getActionCommand());
Object o = event.getSource();
if (o instanceof JMenuItem) {
Component c = SwingUtilities.getRoot((JMenuItem)o);
System.out.println("Root: "+c);
}
}
};
}
}
------------------------------------8<-------------------------------
- 1
- 1
- void method? Hello,
I am not sure were to put the return, i want to return the sum of the 3
digits, but it gives me an error becouse, it expect a void method
Irlan
public static void main(String[] args) {
//declareer getal
long getal = 456;
//invoke method
Sumdigits(getal);
}
//method declaration
public static int Sumdigits(long n){
int num2 = (int)n % 10;
int num1 = (int)n / 10;
int num0 = (int)num1 % 10;
int num100 = (int)n / 100;
return
System.out.println("de sum is" +num2+ "+" + num0 + "+" +num100);
}
}
- 2
- Applet Issues!!Hey, Im Attempting to create an applet that will open a connection to my
application server, the application server WILL be on the same machine
that the applet will be loaded from, i.e. the app server is on the same
machine as the web server. here is my code (sorry for the bad standards)
public class ClientConference extends Applet {
private ObjectOutputStream output;
private ObjectInputStream input;
private String message = "";
private String chatServer;
private Socket client;
//----------------------------------------------------------------------//
public ClientConference( String host ) {
chatServer = host;
ClientConference application;
application = new ClientConference( "149.153.130.2" );
application.runClient();
}
//----------------------------------------------------------------------//
private void runClient() {
try {
connectToServer(); // Step 1: Create a Socket to make connection
getStreams(); // Step 2: Get the input and output streams
processConnection(); // Step 3: Process connection
}
// server closed connection
catch ( EOFException eofException ) {
System.err.println( "Client terminated connection" );
}
// process problems communicating with server
catch ( IOException ioException ) {
ioException.printStackTrace();
}
finally {
closeConnection(); // Step 4: Close connection
}
} // end method runClient
//----------------------------------------------------------------------//
private void connectToServer() throws IOException{
client = new Socket( InetAddress.getByName(chatServer), 8000 );
}
//----------------------------------------------------------------------//
private void getStreams() throws IOException{
output = new ObjectOutputStream( client.getOutputStream() );
output.flush();
input = new ObjectInputStream( client.getInputStream() );
output.writeObject( "Client Connected" );
output.flush();
}
//----------------------------------------------------------------------//
private void processConnection() throws IOException{
do { // process messages sent from server
// read message and display it
try {
message = ( String ) input.readObject();
}
catch ( ClassNotFoundException classNotFoundException ) { }
} while ( !message.equals( "TERMINATE" ) );
}
//----------------------------------------------------------------------//
private void closeConnection(){
try {
output.close();
input.close();
client.close();
}
catch( IOException ioException ) {
ioException.printStackTrace();
}
}
//----------------------------------------------------------------------//
private void sendData( String message )
{
// send object to server
try {
output.writeObject( "CLIENT>>> " + message );
output.flush();
}
// process problems sending object
catch ( IOException ioException ) { }
}
//----------------------------------------------------------------------//
} // end class Client
If anyone could even hasard a guess at the issue I would appreceate it,
also here is output from the java console if its anyhelp.
load: ClientConference.class can't be instantiated.
java.lang.InstantiationException: ClientConference
at java.lang.Class.newInstance0(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Thanks in advance I really appreceate any help
Niall
- 2
- SAX: continue parsing in included file(s)Currently I use <include>foo.xml</include> [1] in order to include foo.xml
into bar.xml (for example). Since I am moving the parsing to Java, using
SAX I was wondering what the best way is to implement this feature. How do
I "redirect" the reading to another file via a handler?
IIRC, another option might be to use &foo; [2] and include the file that
way, possible combined with a SAX filter to translate <include>foo.xml
</include> into &foo; ?
Any suggestions?
[1] I used in the past a parser (not with Java) that as far as I know was
not able to handle this:
[2] <!ENTITY foo SYSTEM "foo.xml"> , see
http://xml.silmaril.ie/authors/includes/
--
John MexIT: http://johnbokma.com/mexit/
personal page: http://johnbokma.com/
Experienced programmer available: http://castleamber.com/
Happy Customers: http://castleamber.com/testimonials.html
- 5
- networking problemIm connecting an applet to my own simeple server useing
connection = new Socket( getCodeBase().getHost(), 2001, true );
But no matter where I open the applet, it allways say's the same ip is
connecting, the ip the simple server is running on. any idea's?
- 7
- squeezing the use of memoryHi,
Qick question about the use of int Vs. the use of short,char,byte
in 'for' loops. Will it affect the memory utilization/performance at all ?
If yes, to what extent, especially considering a program which uses
looping extensively and doesn't need the entire 'int' range.
Generally people just go ahead and use 'int' in loops...
Awaiting your thoughts,
Asif
- 7
- how do I use String's format? not working on XPimport java.lang.String;
...
public void paint(Graphics g) {
Graphics2D comp2d = (Graphics2D)g;
Dimension appletSize = this.getSize();
appletsize_x = appletSize.width;
appletsize_y = appletSize.height;
String sx=String.format("%d", appletsize_x);
String sy=String.format("%d", appletsize_y);
g.drawString(sx, 200,30);
g.drawString(sy, 200,60);
g.setColor(Color.red);
g.fillOval(x_pos - radius, y_pos - radius, 2*radius, 2*radius);
}
...
}
ballapplet.java:101: cannot resolve symbol
symbol : method format (java.lang.String,int)
location: class java.lang.String
String sx=String.format("%d", appletsize_x);
^
ballapplet.java:102: cannot resolve symbol
symbol : method format (java.lang.String,int)
location: class java.lang.String
String sy=String.format("%d", appletsize_y);
^
2 errors
--
------------------------------------
Jim Michaels
for email, edit the address
RAM Disk is *not* an installation method.
- 9
- Signed code runs using WebStart in 1.4 but not 1.5I have a signed application that runs flawlessly under WebStart in 1.4
JDKs/JREs (on WinXP/2K, Linux and MacOS X) that refuses to run under
WebStart in 1.5 JDKs (on both Windows and Linux; haven't tried on MacOS).
The error occurs when the certificate is validated (this is from 1.5.0_03):
java.security.cert.CeritificateException: Check leaf key usage failed in
certificate
at
com.sun.deploy.security.CertUtils.checkUsageForCodeSigning(CertUtils.java:102)
...
I've tried 1.5.0 (Windows & Linux) and 1.5.0_03 (Linux), with the same
error each time. I know of several others who have also been unable to
run my application under 1.5.0; I don't know of anyone who has been able
to run it under 1.5.0.
I'm using a code-signing certificate bought from Thawte. I've tried
using jarsigner from both 1.4 and 1.5, but get the same results each
time. From the exception, it seems likely that 1.5.0 doesn't believe
that the certificate used to sign the code can be used for code-signing,
but I don't know why it would come to this conclusion.
I've successfully run this app using WebStart under 1.4.2_01, 1.4.2_03
and 1.4.2_06, on Linux and WinXP/2K (ie these JDKs all successfully
validate the certificate used to sign the app and prompt the user as
expected), plus various Apple 1.4 JVMs.
Google hasn't been of any assistance, so any help would be greatly
appreciated.
Cheers,
Damian
- 12
- Wholesale Swiss Rolex Oyster Perpetual DateJust White Gold-ss Men's Watches SRX024 Discount, Fake WatchWholesale Swiss Rolex Oyster Perpetual DateJust White Gold-ss Men's
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time ?standard feature on all genuine Rolex watches)
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Screws in the links, not pins
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Serial band/number on last link/lugs
Standard Jubilee-band clasp, with serial number and steelinox markings
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All the appropriate Rolex markings in the correct places
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- 14
- Where did Castor go?The www.castor.org project seems to be gone. I loved this XML-Java
binding framework and I am wondering if anyone are aware of what has
happened to it?!
Thanks,
Casper
- 15
- question concerning downcasthello guys,
Curiosity made me take a look at the tomcat 's implementation of the servlet
API.
The HttpServlet class, which can be subclassed by http servlets, contains
the "service" method that is invoked by the servlet container in order to
pass a web request to a particular servlet. The method accepts a
ServletRequest and ServletResponse object as arguments, and downcasts them
to HttpServletRequest and HttpServletResponse respectively and then calls a
"service" method implemented by the same class:
public void service(ServletRequest req, ServletResponse res) throws
ServletException, IOException
{
HttpServletRequest request;
HttpServletResponse response;
try {
request = (HttpServletRequest) req;
response = (HttpServletResponse) res;
} catch (ClassCastException e) { throw new ServletException("non-HTTP
request or response"); }
service(request, response);
}
}
How is it possible to do so, as the ServletRequest interface is more generic
than the HttpServletRequest (they have a hereditary relationship
HttpServletRequest== extends ServletRequest)?
TIA
|
| Author |
Message |
Marmagya
|
 Posted: 2004-1-14 2:59:00 |
Top |
java-programmer, JDBC Driver
Hello,
How can I find out which JDBC driver is available on my system? I
am working on a linux server. I am trying to learn JDBC programming and
am having problems about which JDBC driver to use.
Regards
Marmagya
|
| |
|
| |
|
Wendy S
|
| Posted: 2004-1-14 3:17:00 |
Top |
java-programmer >> JDBC Driver
"Marmagya" <email***@***.com> wrote
> How can I find out which JDBC driver is available on my system? I
> am working on a linux server. I am trying to learn JDBC programming and
> am having problems about which JDBC driver to use.
What database are you using? Examples might be Oracle, Sybase, UniData,
Cloudscape...
With that information, someone can suggest what to look for on your system.
--
Wendy in Chandler, AZ
|
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Markku Salminen
|
| Posted: 2004-1-14 3:19:00 |
Top |
java-programmer >> JDBC Driver
> Hello,
> How can I find out which JDBC driver is available on my system? I
> am working on a linux server. I am trying to learn JDBC programming and
> am having problems about which JDBC driver to use.
It depends on the database you have. Driver are usually
in some JAR-file. I use PostgreSQL in my home computer and
driver is in file /usr/share/pgsql/pg73g1jdbc2.jar
This jar-package location must be found in CLASSPATH.
First thing to do is look for your database documentation
what is the name of the driver file. In same document there
is also told how to use the driver.
- Markku -
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Joe Kulig
|
| Posted: 2004-1-14 10:40:00 |
Top |
java-programmer >> JDBC Driver
You have to goto the database manufacturer and get their JDBC driver.
"Marmagya" <email***@***.com> wrote in message
news:mnXMb.11$email***@***.com...
> Hello,
> How can I find out which JDBC driver is available on my system? I
> am working on a linux server. I am trying to learn JDBC programming and
> am having problems about which JDBC driver to use.
>
> Regards
> Marmagya
>
|
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Marmagya
|
| Posted: 2004-1-14 14:04:00 |
Top |
java-programmer >> JDBC Driver
Hi all,
Thanks a lot for your responses, though I missed out on
specifying the database. I use Oracle. As you suggested, I will look
into the documentation of this database and will find out the driver.
Then I will ensure that I have the corresponding jar files available in
my classpath.
Thanks a lot for your help.
Regards
Marmagya
Wendy S wrote:
> "Marmagya" <email***@***.com> wrote
>
>>How can I find out which JDBC driver is available on my system? I
>>am working on a linux server. I am trying to learn JDBC programming and
>>am having problems about which JDBC driver to use.
>
>
> What database are you using? Examples might be Oracle, Sybase, UniData,
> Cloudscape...
>
> With that information, someone can suggest what to look for on your system.
>
|
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| |
|
kaeli
|
| Posted: 2004-1-14 22:25:00 |
Top |
java-programmer >> JDBC Driver
In article <075Nb.20$email***@***.com>, email***@***.com
enlightened us with...
> Hi all,
> Thanks a lot for your responses, though I missed out on
> specifying the database. I use Oracle. As you suggested, I will look
> into the documentation of this database and will find out the driver.
> Then I will ensure that I have the corresponding jar files available in
> my classpath.
> Thanks a lot for your help.
>
Looks for classesxxx.zip and nls_charsetxx.zip.
For 8i, I use classes111.zip and nls_charset11.zip.
I got them from the Oracle site.
Note: they're zips, not jars, for Oracle.
--
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Index ‹ java-programmer |
- Next
- 1
- Loading jdbc jars and classes in the application default classloader dynamically..In our application, the JDBC jar files are stored in pre configured
location. say c:\server\libs\1.jar, 2.jar
We don't want to include these jars file in the class path. However,
whenever, we receive a jdbc request, we want to be able to load all the
jars located in this location and then do the basic jdbc call
sequence...
e.g. Class.forname("com.mydriver.SQLServerDriver");
Connection conn = DriverManager.getConnection(
"jdbc:mydriver:sqlserver://sqlserver1:1433;DatabaseName=Mydb;User=****t;Password=*****"
);
How ca i do this?
I tried the following code but doesn't help... I keep getting the
java.sql.SQLException: No suitable driver error. After somedebugging, I
found that the Drivermanager uses some getCallerClassLoader and that
doesn't match the class loader of com.mydriver.SQLServerDriver.
How do i make the loading using the default class loader at the same
time including those jar files?
String x = "kjds";
File f = new File("D:/server/libs");
File[] jarFiles = f.listFiles(new ExtentionFilter("jar"));
URL[] urls = new URL[jarFiles.length+1];
int i=0;
for(;i< jarFiles.length;i++){
try{
urls[i] = jarFiles [i].toURL();
}catch(Exception ex){}
}
ClassLoader z = new URLClassLoader(urls,
x.getClass().getClassLoader());
try
{
//Class DriverClass =
z.loadClass("com.mydriver.SQLServerDriver");
//Driver dd = (Driver)DriverClass.newInstance();
// DriverManager.registerDriver(dd);
Driver x =
(Driver)Class.forName("com.actuate.actuatedd.jdbc.sqlserver.SQLServerDriver",
true, z);
String cnstr =
"jdbc:mydriver:sqlserver://sqlserver1:1433;DatabaseName=Mydb;User=****t;Password=*****"
Connection conn = DriverManager.getConnection( cnstr );
}
catch (Exception e)
{
e.printStackTrace();
}
- 2
- struts or expresso or turbine?hi..
i've been reading the struts developer and it mentions that i want to
create a web application from scratch i should use either turbine or
expresso..
i'm looking for a free, main stream web framework, that can be used
with eclipse.
can anyone tell me about any of these and how they compare?
- 3
- [JSF] How to determine the WEB-INF path of the current web application?Hello everybody,
I'm new to the Java world writing my first Java web application with JSF 1.1
and Tomcat 5.5. I have the following problem:
I've created a Properties file and placed it in the WEB-INF directory of the
web application. The file contains several configuration options like
database parameters. I want to open this file within my web application
with a FileInputStream which I pass to the load() method of a Properties
object. Unfortunately I was unable to determine the path of the WEB-INF
directory of the current web application. I don't want to write the path
hard coded into the source code.
Maybe my way is not the correct "Java way" of solving this kind of problem
so I'm not only interested in an answer to my question but also in
suggestions how to solve this problem in a better way.
Thank you!
--
Sincerely
Sven Jacobs
- 4
- Tomcat & SSL & a certificate generated by VerisignAttempting to SSL enable tomcat 4.04. Have implemented JSSE and SSL
works fine when I create a keystore with a self generated certificate.
keytool -genkey -alias tomcat -keyalg RSA -keystore .keystore
We now want to cutover using a production certificate. We create a
.cer file by accessing our production web site and export the
certificate to a .cer file.
then using the keytool we import the .cer file
keytool -v -import -file prod.cer -keystore .keystore
When we inspect the .keystore file using the -list switch we see the
certificate.
Now when we implement the .keystore in tomcat, only the original self
generated certificate is presented.
So, using the keytool we delete the original self generated
certificate so we are only left with the newly imported production
certificate.
When we implement this .keystore file with only the production cert,
the browser and tomcat fail to negotiate. Tomcat binds to port 8843
but the ssl negotiation is hosed.
Has anybody ever gottent tomcat & ssl to work with a non self
generated certificate? Can you please help?
Thanks,
email***@***.com
- 5
- problem with methods on a bound classHi,
I've been fiddling around with JavaScript.pm, which is very cool, I have to
say, I've bound a class, and sucessfully bound an object, and i can read
from the object's properties, and execute it's getter/setter functions, but
for some reason i cannot get the object's methods to work..
here's a cleaned up version of what i've been testing with:
$js->bind_class(
name=>'Foo',
methods=>{
test => \&Foo::test
},
properties=>{
testy =>{
flags => JS_PROP_READONLY | JS_PROP_ACCESSOR,
getter => \&Foo::test_getter,
}
}
);
my $obj = new Foo();
$js->bind_object('obj', $obj)
(where package Foo has a 'test' method)
....
now in js: 'obj.testy' (the property) works fine, but 'obj.test()' (method)
just doesn't.. there seems to be no indication that it's successfully bound
(everything just says it's not defined).. getters and setters work, but
methods just don't seem to..
Any clues as to what's going on?
Dan
- 6
- Java developer needed (Open Source project)Java developer needed, pref. with socket prog exp
---------------------------------------------------
Programming Language :: Java Competent 6 Mo - 2 yr
Socket programming(Java):: Want to learn < 6 Months
Project page: http://freelancebot.sourceforge.net/
- 7
- Generating excel sheets through JSPHi,
I have previously created excel sheets in JSP in weblogic, and i get
the result accurately.
I had used;
<%@ page contentType="application/vnd.ms-excel" import="java.sql.*"
language="java"%>
at the top of the page and,
<meta http-equi="Content-Type" content="application/vnd.ms-excel;
charset=iso-8859-1">
in the head tag of my page.
Now I'm using tomcat 5.5 and this is just not working....
Can someone help me out with this?
- 8
- ClassDefNotFoundI'm having a lot of trouble trying to run small applications that have compiled
fine. No matter what I try attempting to execute any class file gives me this
message:
java -classpath "." TryWindow.class
Exception in thread "main" java.lang.NoClassDefFoundError: TryWindow/class
I've tried setting my class path the the current working directory in my
environment, specifying the current directory with the -classpath switch,
specifying "" with the class path switch, running it as an unprivileged
user, running it as root, and manipulating the permissions and the result
has been the same. I also rebooted to Windows and tried it with the
NetBeans ide. What am I doing wrong? According to what I have read
java should be able to find classes in the current working directory.
Here is the code for the example I tried:
import javax.swing.*;
public class TryWindow{
static JFrame aWindow = new JFrame("This is the Window Title.");
public static void main()
{
aWindow.setBounds(50, 100, 400, 150);
aWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
aWindow.setVisible(true);
}
}
Thanks in advance.
Mitch_M
- 9
- Kodak v Sun; patent law gone all wrong?If in 1995 Sun Microsystems, Inc. changed the name of OAK to Java and
modified the code for the Internet, how did Sun infringe the patents
Kodak acquired from 'Wang' in 1997? What damning evidence did Kodak have
that in 1995, Sun incorporated the 'Khoyi' method, thereby infringed the
patents?
The "Khoyi patents", named after Dana Khoyi - an ex-Wang engineer,
"covered a method by which a program can get help from another computer
application to complete a task", which they claim is the way Java
operates and that Sun has therefore infringed the Khoyi patents..
Whose intellectual property is Java? Surely Java was patented in 1995,
just after the change? Were the Wang 'Khoyi' patents and Sun 'Java'
patents identical? I take it Wang patented their software years before
Sun did? Does anyone know what year?
If the two were identical or similar, isn't it possible that in a world
of 6,395,379,218 people, it is more than likely that two or more people
might have the same ideas? I find it difficult to believe that Sun
infringed Kodak's patents, but rather that Kodak got a little too
desperate given it's not doing so well in this 'digital' age and had to
lay off some 15,000 jobs worldwide a month ago "because of declining
demand for consumer film and colour photographic paper"..
How on earth can an eight member jury of lay people understand "patent
law" to deliberate and find in favour of Kodak? I don't understand how a
jury could possibly fathom the complexities of patent law, without any
background or education in the legal arena, and find in Kodak's favour?
There are a lot of questions that I have to things that don't add up,
like; Java is freely downloadable, so how can any jury find in favour of
Kodak who wanted damages of $1.06 billion in past royalties??
How did Kodak prove that Sun had access to its patents?
If Kodak is so sure that Sun infringed patents, why did it bother to
agree to the $92 million settlement? Surely they believed they would be
awarded $1.06 billion or even more..? accepting such a small amount (for
them) is silly, it sounds to me like they thought they wouldn't win..
This case is a perfect example why juries should NOT be involved in
patent suits.
Sun should not have settled the case, it should have seen the case
through and appealed the prospective travesty of justice..
Does anyone agree with me here? I'd be interested in other people's
opinions on this issue. A public debate, anyone?
- 10
- why "synchronized" with wait/notify ?I know the language requires it and what exaclty happens with
wait/notify.
BUT it appears that the whole wait notify protocol should work just as
well without acquiring a monitor lock on the target object...
I've read something about why we need to have a thread own a monitor on
the object (key) that is waiting on, something about race condition.
but icant wrap my head around it, could someone care to walk me through
it please using a scenario where it would not work as expected.
So why would this not work (logic- forget the illegal monitor state
execption)
ThreadA
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|
key.wait() //suspend threadA and add to waitset of key
ThreadB
|
|
key.notifyAlll; //Wake up one of the threads in the waitset of key
Thanks
- 11
- 12
- OOM detectionHi,
I'm looking for a way to detect that the JVM is reaching an out of
memory situation. But, I don't want to do this by means of catching
an OutOfMemoryError, because by that time the ship is already
sinking. I came up with a solution that uses the Reference Objects
API, but I don't know if it will do the job correctly.
Below is a demo. Please give me some feedback on this.
I also tried it out using a SoftReference, but then it gives an
OutOfMemoryError eventually. Is this behavior JVM dependent?
CC me,
Frank.
/*
* Run with: java -verbose:gc Test
*/
import java.lang.ref.*;
import java.util.*;
public class Test extends Thread {
private ReferenceQueue queue = new ReferenceQueue();
private Reference pr;
private static Stack stack;
public void run() {
while(true) {
Object o = new Object(); // dummy object
pr = new WeakReference(o, queue);
o = null;
try {
queue.remove(); // when our dummy object gets finalised we continue here...
}
catch(InterruptedException e) { }
System.out.println("OOM");
stack.clear(); // prevent OutOfMemoryError here...
}
}
public static void main(String [] args) {
stack = new Stack();
new Test().start();
while (true) {
stack.push(new Object());
}
}
}
- 13
- Store XML to databaseI have some details from a jsp page, that i will store in XML format,
using DOM. I have created this much and now i want to store this XML
file in the database. How to do this ? the xml is available as a stream
in my program.
help of any kind is appreciated
thanks in advance..
sarath
- 14
- why it doest draw ???in the below short write
i try to write an Thread examle that try to draw lines in every second
from (0,0) to (x, y).
x and y are random between 0..255
with first come to tWork (Thread) it draws, but next second and next
seconds it doesnt do any thing.
g and gr are the same and initalized
i cheked them with this command :
System.out.println(gr.equals(g)); //it prints "true"
question is why it doesnt draw line after second 1 ?
polat
------------------------------------------------------------
package mypackage1;
import java.applet.*;
import java.awt.*;
import javax.swing.JButton;
class tWork extends Thread
{
Graphics gr;
public tWork(Graphics g)
{
gr = g;
System.out.println(gr.equals(g)); //it prints "true"
}
public void run()
{
int x, y;
while (true)
{
x = (int)(Math.random()*255);
y = (int)(Math.random()*255);
gr.drawLine(0, 0, x, y);
try
{
this.sleep(1000);
}
catch (Exception e) {}
}
}
}
public class Basla extends Applet
{
Thread t;
public Basla()
{
this.setSize(300,300);
}
public void paint(Graphics g)
{
t = new tWork(g);
t.start();
}
}
- 15
- Writing a generic InputBoxHi,
I wont tell my old way but I have rewritten my InputBox class as having
the following important snippets:
public class InputBox extends JDialog {
private ActionListener okAction;
public InputBox(ActionListener a, JFrame f, String label, String
title, String defaultText) {
okAction = a;
getMyOkButton().addActionListener( new ActionListener() {
public void actionPerformed(ActionEvent e) {
okAction.actionPerformed(e);
dispose();
}
});
public String inputText() {
return control.getText();
}
}
Code uses it as follows
ActionListener okAction = new ActionListener() {
public void actionPerformed(ActionEvent e) {
try {
myObject.setURLName(hyperlinkInputBox.getInputText());
} catch (Exception ex) {
Debug.LogException(this, ex);
}
}
};
hyperlinkInputBox = new UIInputBox(okAction, "Insert
Hyperlink",parentFrame,"URL:",null,300);
hyperlinkInputBox.setVisible(true);
I dislike having to make hyperlinkInputBox a private variable in the
calling class in order to reference it within the okAction
ActionListener. Same goes for myObject.
I guess it is not *too* shabby but can anyone improve my architecture?
thanks
Tim
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