| SetProperty per oggetti Complessi |
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Index ‹ java-programmer
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- 1
- Looking for a gui class to pop up to let user choose directory and filenameHi,
When I output something to a file, I hope something pop up that let the
user to select the directory and input the file name. I don't know how
to do it. I can hard-code the file name in my program and use
PrintWriter class to do it, like:
PrintWriter outputStream = new PrintWriter(new FileOutputStream("out.txt"));
outputStream.println("hello world");
outputStream.println("how are you?);
Thank you very much for your help.
- 1
- MySQL / MS SQL - jsp developmentI am working on a jsp project that uses a MySQL database,
i wonder if the backup (.sql) file of MySQL can be executed on a MS SQL
server.
sorry for sort of off-topic of the forum.
Thanks so much
ran
- 2
- NumberFormatException:please help me......!!!Hi,
i have a question and i need your help.
I'm developing a java application that have to import data from a txt
file as
3.2 2.1 4.5 6.7 2.3 4.5 3.4 5.5
2.1 3.2 4.7 2.1 3.5 6.7 5.6 3.1
The application counts rows number and columns number and import data
into a bidimensional array of double type.
I compile my code and i have this error
Exception in thread "main" java.lang.NumberFormatException: For input
string: "3
..2 2.1 4.5 6.7 2.3 4.5 3.4 5.5"
at sun.misc.FloatingDecimal.readJavaFormatString(Unknown
Source)
at java.lang.Double.parseDouble(Unknown Source)
at AddDb.ReadArray(AddDb.java:51)
at AddDb.main(AddDb.java:97)
How can i do?
Please help me with code, i'm a new java user...
Here is my code
import java.util.*;
import java.io.*;
public class AddDb {
private static String fileName="Dato.txt";
private static int Ncolumns=0;
private static int Nrows=0;
public int ColumnsNumber(BufferedReader br)throws IOException {
String line = br.readLine(); //legge una linea di testo terminata
da /n o /r e la restituisce come stringa
StringTokenizer st = new StringTokenizer(line);
Ncolumns=st.countTokens();
return Ncolumns;
}
public int RowsNumber(BufferedReader br)throws IOException {
String line = br.readLine();
while (line != null) {
Nrows++;
line = br.readLine();
}
return Nrows;
}
public double[][]ReadArray(int Nrows,int Ncolumns,BufferedReader
br)throws IOException
{
double[][]x=new double[Nrows][Ncolumns];
for(int i=0; i<Nrows; i++)
{
StringTokenizer tok=new StringTokenizer(br.readLine(),"");/
for(int j=0; j<Ncolumns; j++)
{
x[i][j]=Double.parseDouble(tok.nextToken().trim()) }
}
for(int i=0; i<Nrows; i++)
{
for(int j=0; j<Ncolumns; j++)
{
System.out.println("L'array bidimensionale ?+x[i][j]);
}
}
return x;
}
public static void main(String[] args)throws IOException {
FileReader file = new FileReader(fileName); BufferedReader br =
new BufferedReader(file);
AddDb db=new AddDb();
br.mark(99999);
db.ColumnsNumber(br);
System.out.println("Il numero di colonne e' :"+Ncolumns);
br.reset();
br.mark(99999);
db.RowsNumber(br);
System.out.println("Il numero di righe e' :"+Nrows);
br.reset();
System.out.println("Caricamento dell'array di double in
corso.....");
try
{
System.out.println(db.ReadArray(Nrows,Ncolumns,br));
}
catch(IOException e){
System.out.println(e.getMessage());
}
br.close();
}
}
- 3
- Programming with JCo (SAP)Hi,
I hope there is someone out there with programming experiences in SAP
over Jco.
Unfortunately I have no SAP System here to test my code with.
In the documentation is written:
------
JCO.Repository mRepository;
mRepository = new JCO.Repository("ARAsoft", mConnection);
We invoke the constructor for JCO.Repository with two parameters; the
first one is an arbitrary name, the second one either a connection pool
name or a JCO.Client object. In other words: Both connection pooling and
direct connections are supported. In (web) server applications, we
should always use a connection pool for the repository. The userid used
for the repository has to have sufficient authorizations in SAP for the
metadata access to be possible. Please read the Javadoc for class
JCO.Repository to find out which specific authorizations are required.
You can use one special userid for the repository access and one or more
"normal" userids for the actual application.
------
I have the following code I was able to test on a foreign system:
public JCO.Function getFunction(String repositoryName, String
functionName,
JCO.Client connection) {
IRepository repository =
JCO.createRepository (repositoryName, connection);
IFunctionTemplate ft = repository.getFunctionTemplate (functionName);
return ft.getFunction ();
}
To create the Repository I pass an object of type JCO.Client. I have got
this object from a pool before.
When I understand the documentation corretly I can also pass the pool to
create a Repository. Then there wouldn't be no need to handle with
JCO.Client objects.
But I can not test this and thus I want ask if someone can confirm that
this works.
And another question: Since I don't need any Client objects then, I can
not release them to the pool. Is that ok and happens implicitely, or do
I have to do something else?
--
bye Armin
- 4
- Two Jframe`s - how to setenable(fasle) ?I have problem, in my application I have main jframe, now user click on
jbutton, now I create another Jframe with jprogressbar
i would like to block main Jframe. How to do is ?
- 7
- Aspect oriented Everything?Hello,
Aspect oriented Software development seems to be expanding in the
popular vision of developers, with more and more IDE 'add-ons' and
even more specialized tools,Jboss etc.
I've seen more and more languages integrate AOP,AspectJ (Java),
AspectR(Ruby)etc.Aspect oriented does seem to be the place to go from
a developer standpoint.What I want to know is,if anybody on a
commercial scale is using AOSD to develop commercial products? Is an
Open Source development ever going to gain the trust of industry? It
may be ok for personal projects and other Open Source material but
will your bank ever accept it? Is it the fact that AOP is new and, for
most,confusing or is it the fact that AOP has developed in the
environment it has.i.e Open Source,that may dissuade commercial
development shops from accepting AOP.
What are the main features that may lead to AOSD adoption? Is AOP the
next step on from OOP? Is it another chance for some of the lesser
utilised languages to step up to Java and C++? Your opinions on the
subject would be appreciated? Design features are one thing but
widespread adoption is another, or is it?
Anything you care to add on the subject would be appreciated on this
short questionnaire.
http://www.geocities.com/aspect505
Thank you for your participation.
Shane Hassan.
http://www.geocities.com/aspect505
- 11
- Manifest.mf Class-path troubleHi group!
I'm deploying an application with this structure
app
app/app.bat
app/lib/app.jar
app/lib/another.jar
app/plugins/other/
where the (windows) batch file starts the application like so:
java -jar lib\app.jar
and the Manifest.mf with that jar puts another jar on the classpath
like so:
Class-Path: another.jar
Now I also want to put any plugin classes that users put into
app/plugins/other/ onto the classpath, roughly like so:
Class-Path: another.jar "../plugins/other/*"
So far I've tried a few variations, but the development cycle is quite
tedious and it ain't workin yet.
I'm wondering:
* use quotes ?
* forward slashes ok on windows or do I need separate versions for Win
vs Unix ?
* end the directory with / (or resp. \) or nothing (../plugins/other) ?
* end the directory with "/*" or possibly "/*.class" ?
Alternatively I could use the java -classpath arg in the batch file,
but I've tried that and it's not working either, so I'm getting the
impression that using the Class-path: line in the manifest somehow
disables the -classpath arg of the java command. Is that so?
YT
- 11
- Webstart ignoring minor J2SE version numbersI'm trying to build my first WeStart aware application. I've JARed it
and assembled my HTML and JNLP files, but am having a lot of trouble
with the <j2se> tag.
I would like my users to use Java 1.4.2 or later. (I have 1.4.2-b28
myself). However, when I use the tag <j2se version="1.4.2+"/>, web
start replys that a JVM of this version is not installed, and that it
cannot find an appropriate JVM to download either. Changing that to
"1.4.2" - the example given in the documentation - creates the same
error. However, "1.4+" download and runs the application.
My app relys on some bug fixes from versions post 1.4.0, and I'd like
my users upgrade to the appropriate JVM. Is there a way to get this
done?
Mark McKay
http://www.kitfox.com
- 11
- Book question on threads"Chris Smith" <email***@***.com> wrote in message
news:email***@***.com...
> Obviously, it's possible to interpret the question in a way that makes
> this answer wrong; it's probably easier, though, to interpret it to make
> this answer right. What you've listed is invalid syntax, and I would
> have a rather strong bias against an interpretation of this question
> that requires you to assume (without seeing code) that the author has
> written code that results in compile-time errors. If that were the
> case, option B should read "the thread was never started because the
> program didn't compile". :)
>
The example had no code. Only the question which I posted. The whole point
of the question though, is to determine which possibilities are... um...
possible.
> To take a guess at a literal explanation, should we assume the author is
> being as literal as you are, the word "access" is very closely related
> to "accessor", the word for a short method that serves to allow someone
> to access a field. More likely, though, the author wasn't excluding
> non-direct access to the variable; the last phrase should instead be
> interpreted as a statement of intent for what the thread wants to do.
>
As I said in my reply to Nigel, questions about programming (similar to
programs about science and math) are very clear-cut. If every word of an
answer isn't true, the answer is incorrect. At least that's how it is in my
experience.
> In the end, when people so frequently post bad questions from
> certification prep books, and it's so widely known that a large majority
> of certification prep books are full of stupid drivel from people who
> confuse the Java language with their own pet mental gymnastics for
> memorizing stuff and possibly also just feel more secure when they ask
> ambiguous questions so that you'll miss some... given all this, why
> would it be a surprise that someone found an ambiguous question in a
> Java certification prep book?
>
No surprise. I just wanted to see if this was indeed one of those ambiguous
questions. Apparently it is. If I saw this question on an actual test, I
think I'd still answer it as I have here, because I haven't really heard a
convincing explanation why not to. It seems that every response either
explicitly or implicitly has something to do with "interpreting the answer"
to mean something slightly different from what it says. I'm still going to
have to stand by my original response to the question: you cannot
synchronize access to a variable. Therefore a thread will never need an
object's monitor in order to access a member variable of that object.
Therefore, a thread will never be waiting on said monitor.
- 12
- Displaying multi-line textHi all,
I want to display text on the screen, I would normally use a JLabel but I
want this text to span over about 3 lines. I am trying to use a JTextArea
but I want the background to be transparent, like the JLabels. I can not
find anywhere in the API on how to do this. Any help or alternative ideas to
using JTextArea would be greatly appreciated.
Many thanks
Ed Keen
- 12
- Fast image scalingHi all,
I'm writing a program which involves drawing several copies of the same
image inside of a JPanel. I have a listener on the mouse wheel to
"zoom in/out", so that every image scales up or down in size at the
same time. I'm having many problems getting this to run smoothly.
I first tried to scale the image just once (since it is drawn many
times) by calling getScaledInstance, saving the resulting image, and
then drawing that lots of times. However, even though I am using
Image.SCALE_FAST, it sometimes takes a while to update the image when
scaling to larger sizes. (Note, the image is 440x250, and I'm never
scaling it larger than double its size.)
The second thing I tried was to use an AffineTransform to scale the
graphics object just prior to drawing the image. This gave slightly
better results during the actual scaling, but it caused random hitches
(half-second pauses where all movement in the program completely
stops), even when I wasn't actively changing the scale. I finally
deduced that the scaling causes some garbage to be created, and the
hitches happened when the garbage collector ran. (I also tried without
the AffineTransform, and just using the width/height arguments in
drawImage to scale on-the-fly, but the results were the same.) Please
also note that when I don't scale the image at all, the drawing is
perfectly smooth and fast.
What I'm doing doesn't seem to be nearly as intensive as what most
people are capable of doing, so clearly I'm doing something wrong. If
anyone could point me in the right direction, I'd be most appreciative!
Thanks!
- 15
- >>>> Sr Java Dev position in MD -- $85/hr <<<<<Hello all!
I'm Anna Rocheva, a recruiter with USTAS Technologies. I'm glad to
present you a challenging opportunity.
Our direct client is a large reputed financial organization based in
Rockville MD, Washington DC Metro area. We are looking for Sr. Java
Engineer who will develop and support a mission-critical J2EE
applications.
Required skills:
?5-7 years of experience of
o OO design and development
o Hard-core Java development
?5-7 years of experience with the following technologies:
o Java (J2EE, Struts, tag library, Servlets, JSP)
o XML
o Web-based applications
o Ant
o SQL
o Oracle
o Unix/Linux
?2+ years of experience with the following technologies:
o Spring framework
o Hibernate
o AJAX
Agile software development practices
?Excellent communication and writing skills
?Product development methodologies
?Experience using software development best practices
?Experience using open source technologies
Compensation:
Up to $90/hr on c2c and $85/hr on w2..
We have outstanding benefits, e.g. 100% family medical insurance, 401K
plan, paid vacations etc.
If you think that the position requirements match your technical
background and expectations, don't hesitate to contact Anna at
301-242-5033 or via email: email***@***.com
- 16
- finding java difficultI know Visual Basic and few other commands in Oracle but I am having
trouble learning high level Java. Should I just read over and worry
about it later? I understand Arrays and If statements but found for
example, " overiding and hiding methods" difficult. It states a
superclass overides a superclass. I am confused!
here is "overiding and hiding methods" from the sun.com site;
An instance method in a subclass with the same signature and return
type as an instance method in the superclass overrides the superclass's
method. (Remember that a method's signature is its name and the number
and the type of its arguments.) You can also override a method with the
same signature that returns a subclass of the object returned by the
original method. This facility (introduced in 5.0) is called covariant
return type and you can see an example in Annotations (in the Learning
the Java Language trail).
- 16
- Pipelining COM portsIs it possible to create a pipeline to virtual COM port (MS Windows)?
I connect a mobile phone to PC over Bluetooth and
[CommPortIdentifier.getPortIdentifiers();] does not enumerate any port,
neither COM1 nor virtual port for mobile phone.
If I use [new FileOutputStream("COM10");] then I can send data to
mobile phone but I can't read the response.
Basically, I need to open a pipeline to file. Where can I find more
information on this topic?
- 16
- DropDown in cell of jTableHi all,
I wish to put a drop down where to choose from when the user edit a certai
cell of a jTable.
The drop down should appear in the position of the cell thas is going to be
edited....
Is it possible? How?
can someone point me in the right direction? (or send a snippet of code ;) )
Thanks.
Mario
|
| Author |
Message |
Annalisa
|
 Posted: 2005-6-8 23:20:00 |
Top |
java-programmer, SetProperty per oggetti Complessi
Salve a tutti,
sto sviluppando un'applicazione web piuttosto complessa in java che utilizza il framework Bluprint della Sun.
In particolare, la mia problematica è legata alla gestione degli oggetti di business nell'interfaccia con l'utilizzo, nelle jsp, dei metodi setProperty e getProperty java.
Gli oggetti che utilizzo sono i seguenti:
‘public class Anagrafica implements java.io.Serializable {
...
private Vector indirizzi;
}
...
public class Indirizzo implements java.io.Serializable {
protected String tipo;
protected String particella;
protected String address;
protected String houseNumber;
protected String zipCode;
...
}
Ciò che voglio realizzare è la visualizzazione nella jsp dell'interfaccia di tanti ‘frame' quanti sono gli oggetti Indirizzo contenuti nel Vector di Anagrafica. Scrivendo, però, ciò che segue:
<jsp:useBean id="..." class="..." scope="session">
<jsp:setProperty name="indirizzo" property="*"/>,
il metodo setProperty non setta le proprietà complesse dell' oggetto vector indirizzo.
Spero di esser stata chiara.
Attendo un vostro suggerimento...
-------------------------
Annalisa Cosmai
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Andrew Thompson
|
| Posted: 2005-6-9 16:20:00 |
Top |
java-programmer >> SetProperty per oggetti Complessi
On Wed, 08 Jun 2005 15:19:37 GMT, Annalisa email***@***.com wrote:
> Salve a tutti,
>
> sto sviluppando un'applicazione web piuttosto complessa in java che utilizza il framework Bluprint della Sun.
> In particolare, la mia problematica è legata alla gestione degli oggetti di business nell'interfaccia con l'utilizzo, nelle jsp, dei metodi setProperty e getProperty java.
> Gli oggetti che utilizzo sono i seguenti:
This apparently translates as..
I am developing a rather complex application web in java that it uses
framework the Bluprint of the Sun. In particular, my problematic one ?
tied to the management of the objects of business in the interface with I
use it, in the jsp, of the methods setProperty and getProperty java.
To Annalisa:-
"Ha il significato inviare a questo gruppo usando la lingua che capite il
pi?bene, ma prego usa Google 'traduce'* gli attrezzi per dare una versione
inglese pure - questo senso la maggior parte dei lettori pu?capire!"
* <http://www.google.com/language_tools?hl=it>
Follow-Ups set to the only one of those groups to which I subscribe.
--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane
|
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Index ‹ java-programmer |
- Next
- 1
- What Lies Beneath-Feature Article in Better Software MagazineWhat Lies Beneath
by Ryan English
According to a recent ABC News/Washington Post survey on identity
theft, 84 percent of Americans polled believe that corporations are not
doing enough to protect customers' personal data. The Privacy Rights
Clearinghouse recently published the results of a survey that found 45
percent of identity theft cases involve hacking. One-third of all
identity theft cases are a result of Web application security
vulnerabilities. These vulnerabilities can be costly and result in the
exposure of large amounts of confidential information. Major public
companies, including Google, T-Mobile, CVS, and MSN, were exploited in
2005 through Web application security vulnerabilities. CardSystems lost
its biggest partner, Visa, when it was announced that information from
forty million credit cards might have been exposed to hackers.
If many hacking attempts are for the purpose of identity theft, it is
difficult to understand why so many organizations continue to install
Web applications on the Internet without first checking for security
defects and vulnerabilities. If you asked a group of developers and
testers if they pride themselves on producing robust, defect-free
applications, all of them would say yes. But if you asked the same
question about secure code, few would have an answer. Yet security
vulnerabilities are software defects. If a product has security
vulnerabilities that will allow a hacker to steal confidential data or
even shut down the application, then a solid, high-quality application
has not been produced.
Learn more:
http://www.stickyminds.com/BetterSoftware/magazine.asp?fn=cifea
- 2
- Reading Values from a text file.Hi,
I have a problem reading in values from a text file. Basically i have a
webservice that gets queries from a database, and i wish to read the
queries in from a text file. I know how to read a text file but what i
really want to say is:
open file;
read first line of file;
use this line as query;
do query processing;
then read next line of query;
.....
.....
....
etc
what i would like to know is there a way of looping through the lines?
Many thanks
Andrew
- 3
- Beautify HTMLHi,
I need to beautify HTML files from within my web application. These
files come from an online editor that writes its output on a single line.
JTidy might be a solution, but there is no documentation and so it's
very hard to test it on the fly. After all, I don't need a complete
parser: a simple formatter/beautifier would be great. Does anyone know
of such a class? Arachnophilia does it, but it's not an API.
Thanks
Mario
- 4
- Tele-conference demoI know Microsoft has teleconference software, can
do tele-presentation, demo
But I prefer do things simple
I am thinking use java.awt.Robot class do
the screen catch every second, then write
to the image into a buffer file pipe
in web server.
Then in the web page create
an applet read from that buffer file pipe.
So when I doing demo, I start my program run
in background, do screen catch, write to web
server.
User just http to my applet page watch my demo.
This is similar to xwatchwin in X11 world.
But X11 world only work in intranet with small
group of people, require expensive X-terminal.
Today every PC has a browser, access to internet.
Do you think this is doable?
Any better idea?
Or such Java program already existed? (tell me the download link)
Thanks!
- 5
- Problem with Java panelsI want to write application with few tabbed panels each with split
panel inside. Some of those split panels should share the same panel
as in code below.
//----------------//
JTabbedPane tabbed = new JTabbedPane();
JSplitPane split1 = new JSplitPane();
JSplitPane split2 = new JSplitPane();
JPanel panel1 = new JPanel()
JPanel panel2 = new JPanel();
JPanel panel3 = new JPanel();
split1.setLeftComponent(panel1);
split1.setRightComponent(panel2);
split2.setLeftComponent(panel2);
split2.setRightComponent(panel3);
tabbed.addTab("1",split1);
tabbed.addTab("2",split2);
//------------------------//
Unfortunately in split1 panel I cannot see panel2 but only panel1. In
split2 panel it all works fine. Why it doesn't work?
--
Lukasz Huculak
email***@***.com
- 6
- instrument panelDoes anyone know of any shareware/freeware to help build an instrument
panel with various gauge types to help build an instrument panel like
in an airplane? It will be implemented in a Java 1.4 application.
Thanks John.
- 7
- Struts html:select question.I want to accomplish....
I have to query a database whic return list of employee records.
In the front end, i have to show, list of all firstName's in a list
box style
(<select multiple> <option>). If user decides to add more employees,
then
i have to validate the name(with no special characters) and proceed to
the
next screen. There i need to show the newly added name in that screen
along
with all other fields empty. So that user can add that fields.
For this, i am doing like this.
When i query database through my Action execute() method, database
returns a set of employee records. I am capturing all those in my
NameBean[] and passing it to JSP.Code looks like this..
NameBean[] name = DatabaseReturnsListOfEmployees...
request.setAttribute("MyNameBean", name);
In my JSP
<select name="allName" multiple>
<logic:iterate id="MyNameBean" name="MyNameBean">
<option> <bean:write name="MyNameBean" property="firstName"/>
</logic:iterate>
</select>
This code populates <select> <option> with all the firstName in the
list box.
Now my JSP looks like a ListBox.
The question is when i tried to add new firstName in the ListBox, how
do i take it to the Action class? Since ListBox MyNameBean is
NameBean[] and the Action's execute() method has ActionForm has form
value. Not a ActionForm[] value. See below.
public ActionForward execute(ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
Thanks in advance
- 8
- How to get a static reference to a genericized class?I can explain much more concisely with an example...
class Cow<C> {
public Cow (Class<C> clazz) {}
}
class Milk<T> {}
class Moo {}
Now let's say I want to create a Cow< Milk<Moo> >. What do I pass to
the Cow constructor?
new Cow<Milk<Moo>>(Milk.class);
This results in the error "The constructor Cow<Milk<Moo>>(Class<Milk>)
is undefined". This is because the constructor is actually
"Cow<Milk<Moo>>(Class<Milk<Moo>>)". How can I get a reference to
Class<Milk<Moo>> without having an instance of a Milk<Moo>?
new Cow<Milk<Moo>>((Class<Milk<Moo>>)Milk.class);
This is better but results in the warning "Type safety: The cast from
Class<Milk> to Class<Milk<Moo>> will not check conformance of type
arguments at runtime". Damnit compiler, I know better than you! ;)
Is there a better solution?
- 9
- Choosing multicast addresshello everybody,
how do I choose a multicast address?
I know that in order to join a group, i just insert the address, but
how will the server, or the other clients knows what is the IP address?
thank you
- 10
- Heap dump file size vs heap sizeHi,
Do you know how heap dump file size is related to heap size itself?
I've multiple heap dumps created using jmap on Solaris using Sun JVM
1.5.0_09 and somehow filesize doesn't relate to heap size itself.
Disproportions are quite big actually (even 500MB - 1GB)
Michal
- 11
- BigDecimal Builder and immutability...Our application uses BigDecimal, and BigDecimal is immutable. Immutability
is certainly a good thing, but it also means that there are a lot more
memory allocations (and collections). That's ok, we are all happy that
Strings are immutable, but Java also gives us StringBuilder and
StringBuffer. Is there anything similar for BigDecimal?
BigDecimal operations are the hotspots in our application and the GC is also
very busy collecting all the objects. Unfortunately double are not good
enough for us. Ideally we would like something like C# Decimal: a 128bit
decimal number (not floating point, but decimal), I have not actually used
this, but from what I have heard it is what we would need..
I googled the web for a fixed precision decimal class for Java, for an
immutable version of BigDecimal, etc... I could not find anything. Do you
know of anything that could help us?
Thanks,
Tommy
- 12
- Strange problem intersecting java.awt.PolygonHi everybody,
I have a strange problem. I am defining a polygon and I try to see if
it intersects other rectangular shape. Specifically:
java.awt.Polygon pol = new java.awt.Polygon();
pol.addPoint(1, 0);
pol.addPoint(1, 1);
pol.addPoint(0, 1);
if (pol.intersects(0, 0.9, 0, 0.1))
{
System.out.println("Intersects here!");
}
else
{
System.out.println("Do not intersect here!");
}
And it says: "Do not intersect here!". I'm confused. There should be
an intersection...
I also tried with:
if (pol.intersects(-0.01, 0.09, 0.01, 0.01))
{
System.out.println("Intersects here1!");
}
else
{
System.out.println("Do not intersect here1!");
}
And it says again: "Do not intersect here!".
I'm really confused! I hope you can help me!!
About the context of my problem: I have a polygon P and a rectangle R.
I need to check if R intersects P. If just some points in the boundary
of P match with points of R, that's also an intersection for my
purposes (that's why I enlarge R a little bit -0.01 pixels in each
direction, for example- before calling "intersects"). However, it
doesn't work as expected.
I hope you can give me some idea about why this isn't working and how
to solve it!!
Thanks a lot in advance,
Sergio
- 13
- ConcurrencyHi,
I have a program with two classes. One class works out a value and
returns it in the form of an array, the other class adds together all
of the arrays returned by the first class.
What I'm trying to do is get the processes running concurrently, so
while the first process is working out all the values, the second is
adding them all up.
I currently have something like this which it working but I'm unsure
whether it is actually concurrent:
for(int x=1; x<=y; x++)
{
getValue P = new getValue();
int[] temp = P.calculateValue(x);
arrayAddition C = new arrayAddition() ;
total = C.addArrays(total,temp);
}
I've also experimented with a buffer but with no luck.
Any help would be appreciated,
Thanks,
Ed
- 14
- Library for distributed systemsI'm looking for a good Java library for doing a distributed app. The
requirements:
* A master machine must be able to dispatch asynchronous messages to slave
machines
* When messages come back, the library must notify the app on the master
machine
* There should be a timeout on the messages
* If the master gets no response from a slave, it should mark the connection
dead and automatically connect to a backup machine. (I suppose it would be
easy to do this in the app).
* Message passing should be fast.
* The API should be reasonably simple.
Does such a library exist?
- 15
- Java SDK on Linux (problem)I have a Java SDK (j2sdk1.4.1_02) installed on a Linux system (2.2.14).
All seemed to be going well until I noticed something a bit strange.
Running a java app appears to result in the launch of over a dozen
consecutive processes. Suspecting the possibility of a weird, multi
threaded app, I wrote a small test program, Hello.java (appended below).
Same behaviour. Other than setting the CLASSPATH environment variable
appropriately and unpacking the kit, the system appears to have no other
java-specific configuration settings that I can find.
Any ideas?
// Hello.java
package hovnanian.examples.gui;
import javax.swing.*;
import java.awt.*;
public class Hello extends JFrame {
public static void main(String[] args) {
Hello h = new Hello();
}
public Hello() {
super("Hello");
String message = "Hello world!";
Label lbl = new Label( message );
this.getContentPane().add(lbl);
this.pack();
this.setVisible(true);
}
}
--
Paul Hovnanian mailto:email***@***.com
note to spammers: a Washington State resident
------------------------------------------------------------------
Applying information technology is simply finding the right wrench
to pound in the correct screw.
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