| JNI: call C-main program from Java |
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- 2
- sourse & installationhere i'm for asking to u all that how can i install or download java
run time base running with console via internet.
- 2
- Help! I don't know where to turn.> Then I went to java.sun.com and decided I have old packages and was
> going to upgrade everything. As far as I can tell, I downloaded the
> following:
>
> - the JS2E 1.5.0 (?)
> - the JDK
> - the JVM
> - the NetBeans 4.1 (?) bundle
> - the documentation tree
>
> So this seems hunky-dory. The problem now is two-fold:
>
> (a) I can't start the Java console anymore (I saw it once and it looks
> totally different than the previous version) though everytime I
> doubleclick the coffee mug icon in the Control Panel, it starts a new
> instance of javaw.exe.
> (b) Now my Mozilla Thunderbird 1.6 won't connect to my email server to
> retrieve my email.
>
> Can anyone provide some assistance or point me to the right place?
> Many thanks!
>
> Mike
If you have downloaded the J2SE 1.5.0 SDK (or the JDK 1.5.0) and ran
the installation, you do not need to install JVM (i assume you mean
JRE). The java console will look different if you have installed the
JDK.
I am not sure if you can keep two jdks installed. It is possible, but
if you want to save yourself frustation, uninstall the previous jdk
(and jre. Installing the jdk installs jre too along with it. :) ) and
install the new one.
Dont know about netbeans. Possibly, it needs the JAVA_HOME variable
set.
Also the documentation is totally separate. You just need to unzip to a
folder to read it, and not install. Its just a bunch of html files. Do
not worry about it. You can have as many docs of different versions as
you want.
Probably you messed up the internet settings so the problem with
thunderbird. nothing to do with java i suppose. not sure since i have
not used thunderbird yet.
- 2
- Newbie Question - ArrayLists and methodsHello all (again),
My problem here is that I'm trying to build a list of ArrayLists that
hold data and I want to add the newly derived data into a table where
it's dependent on the first row. A short version of my program to
illustrate what I mean:
import java.util.*;
public class MyProg2 {
public static void main(String[] args) {
List table = new ArrayList ();
List <Integer> data = new ArrayList <Integer>();
data.add(1);
data.add(3);
data.add(4);
table.add(data);
System.out.println ("table(0) = " + table.get(0));
ArrayList <Integer> newNode = new ArrayList <Integer>();
newNode = createNode((ArrayList)table.get(0),0);
table.add(newNode);
System.out.println ("Added in a new row and table is now:");
System.out.println ("table(0) = " + table.get(0));
System.out.println ("table(1) = " + table.get(1));
} //end main driver
public static ArrayList createNode(ArrayList items,int lParen){
int a = 0; int b=0; int c=0;
if (items.size() >= 2){
a = Integer.valueOf(items.get(lParen).toString());
b = Integer.valueOf(items.get(rParen).toString());
c = a + b;
items.remove(lParen);
items.remove(lParen);
items.add(lParen,c);
}
return items;
}
}
(I'm unable to get rid of all the unchecked msgs because putting the
<Integer> tag sometimes made the program uncompilable. Use --nowarn
when you compile this program. :)
Iin this code, row 0 of table is changed in the method while it
creates row 1, but I don't understand why and don't know how to keep
it from changing. From this behavior, it's leading me to believe
ArrayLists are passed by value or is this the way of ArrayLists? I
thought parameters were passed by reference? What am I missing here?
-t
- 5
- [OT] SourceForge AddReleaseTaskOfftopic: A question about HTTPS / Java:
I'm writing an Ant task to automate the SourceForge 'Add release' procedure.
For this I'm using Jakarta Commons Net and HttpClient.
The task can be used in an Ant build file as follows:
<taskdef name="sfaddrelease"
classname="org.xins.util.ant.sourceforge.AddReleaseTask"
classpath="xins-common.jar:commons-net.jar:commons-httpclient.jar"
/>
<sfaddrelease
user="znerd"
password="${password}"
file="build/xins-${version}.tar.gz"
group="71598"
package="71219"
release="${version}"
/>
The login is done using HTTPS. The Commons HttpClient library supports this.
But apparently, the server is not trusted, because I get a
javax.net.ssl.SSLHandshakeException. The message is:
"java.security.cert.CertificateException: Could not find trusted
certificate"
Apparently, I need to get the certificate of sourceforge.net and store it in
a keystore. Perhaps I should use 'keytool -import' for this, in some way.
Questions:
* How do I get the certificate of sourceforge.net?
* How do I store it in a file so that Java will accept it?
Ernst
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email***@***.com mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-java
To unsubscribe, send any mail to "email***@***.com"
- 5
- 5
- Which IDE to choose (more specific than earlier, very similar post)?Hello guys,
I'm C++/Windows programmer and I'd like to smoothly switch to Java. I read
replies to earlier, very similar post, but I didn't even hear about such
IDEs :-(
My question is following: using what IDE can I easily create applets with
controls like edit, list, combo boxes, buttons, tree controls and - this is
very important - have support to draw 3D graphics? Some time ago I was using
Borland JBuilder, but I guess it was not intended for building commercial
releases. I was browsing Sun Microsystems' site and found free "Sun Java
Studio Creator, Early Access". Can I create in it commercial applets using
features that I described above? If not, please advise me something free or
really good enough (read: easy to develop applets) to spend money IDE;
preferably free of course :-)
Generally I focused on "Sun Java Studio Creator, Early Access", but I'm
waiting for your replies.
Please reply, your opinion is crucial for me.
Regards
P.S. I'm not going to create server-side applets. I will be doing applets
run in web browser.
- 8
- using importI'm trying to import the Welomb class in the java divelog tutorial into
another application. But when I type import divelog.* it refuses
the absolute path for Welcome is
d:\Documents\Java\Divelog\src\divelog
the application I'm trying to import it from is at
d:\Documents\Java\Frames\src\frames
I've also tried creating a library (MyLibrary) and pointing to the
divelog.jar file and setting the classpath to point at divelog.jar. I've
then added the library to my project but when I try and create a Welcome
class it says it cant find the class. So neither using a library or
importing work.
I'm using sun java studio enterprise8 (free) does anyone know how to import
the divelog package into my app using an import statement.
I've tried the following with no success
import divelog.*
import Documents.Java.Divelog.src.divelog.*
in both cases I get package diesnt exist
any suggestion welcome!!
- 9
- Use of JVM id and Event Notifier patternIn our design for event subscription/publication, a JVM id is used to
identify the event channels (or event brokers). The JVM id refers to
an EventChannel on a host and there will be one EventChannel per host.
FYI, More information about Event Notifier pattern is available at:
http://members.ispwest.com/jeffhartkopf/notifier/
Is it okay to refer to JVM id (kernel level details) to identify a
user level class like EventChannel ? I feel that EventChannel should
be referred by some other way.
Any pointers will be appreciated.
B.
- 9
- Newbie:Please suggest ebook or any reading material for creating rich clients interfaces in javaWhile googling I found a very interesting presentation on creating
amazing GUI's in java on this link -
http://developers.sun.com/learning/javaoneonline/j1sessn.jsp?sessn=TS-3548&yr=2007&track=2
. I was very much impressed and really want to read and learn more on
developing such interfaces. So please suggest some reading material
for this.
I know core java and basics of swing.
Still learning java..:)
- 13
- Playing (MIDI) sounds from Java applet (Shepard's Tones)
The applet for endlessly rising/falling scale
(auditory illusion)
on this page is fantastic!
http://www.cs.ubc.ca/nest/imager/contributions/flinn/Illusions/ST/st.html
How is this done?
(I'm assuming it uses MIDI.)
Is this sound applet playable from any
java-enabled browser on any Windows system?
How about on Mac or Unix?
I'm asking because I want to write
Java programs that plays simple
2-part inventions by Bach.
Thanks.
http://geocities.com/SOBlikeMIDIs/
__________________________________
Do you Yahoo!?
The New Yahoo! Shopping - with improved product search
http://shopping.yahoo.com
- 13
- JTree with dynamically adjusted row height during editing.I have extended JTable so that the installed editor for a cell checks
at each keystroke whether it must adjust the row height in order to fit
the content in the cell. This is easy to do with a document listener
which just starts a thread on each insertion to check for a height
change, and then calls setRowHeight on the appropriate row.
However, it does not seem to be so simple to do the same thing with a
JTree. setRowHeight cannot be called on a specific row, and with
rowHeight set to 0, the tree cells are only resized when the tree
manager itself queries the height. There does not appear to be a way
to get the editor to do this directly.
Does anyone know how to get this effect? It allows for something much
like a regular text outliner using JTree and I would think lots of
people would have wanted to do this in the past, but I havent found
evidence that it has been done.
- 14
- Synth L&F as jarHello,
i am trying to build a L&F basedf on Synth but now i have problems
using the L&F in another project. I pack the L&F into jar add it to a
projects classpath but it is not possible to access the images
contained in the jar. I know that resources from a jar should be
accessed by:
MyResourceBase.class.getResource("path/relative/to/the/MyResourceBase.png")
the problem is that its not me who accesses the images but synth. AND
when i look into synths code the images should be loaded by:
new ImageIcon(url, null).getImage()
with url is the return of:
private URL getResource(String path) {
return _resourceBase.getResource(path);
}
That looks correct to me but it does not work. Has anyone build his
synth L&F and got it to work from a jar? If that does not work, what is
a custom L&F good for if it can not be deployed as a jar?
I am very thankfull for all hints
Harri E.
- 14
- A specific external package import from javacWhich file(s) are required?
Where should these file(s) go?
What's the javac syntax to compile Test16 into ...\class\?
Given this directory structure:
C:\java\java\jTidy\Test16.java
C:\java\org\w3c\
C:\java\class\
Given that Test16.java has this import:
import org.w3c.tidy.Tidy;
SSCE @ <http://thufir.lecktronix.net/java/Test16.java>
Here's what I've gleaned from the 'net:
C:\java> javac -d . org\w3c\* C:\java\java\*
Clearly not correct, but that's my best effort at this point :(
thank you,
Thufir Hawat
- 15
- EnterpriseBean and finalize()Hi Everyone,
I'm trying to learn EJB and picked up a copy of the book "SCBCD Exam
Study Kit" by Paul Sanghera. Inside it, I came across the following
sentence, which piqued my interest because I cannot see a) where this
can be found in the EJB 2.0 specification (actually, I was looking in
the J2EE 1.3 specification), or b) why finalizing a bean would be
interfering with the responsibilities of the container. Here's the
quote:
"... the bean class must not have any finalize() method because by
doing this you would be stepping on the container's toes, since it is
the responsibility of the container to manage the lifecycle, threads,
garbage collection, and so forth."
If anyone can shed a little light on this, and dispel the confusion,
I'd really appreciate it.
Many thanks,
Jono
- 16
- Piped stream help.Hi Everyone,
I have two servlets that both need access to a data file. I would like to
have a 'driver' program that takes care of writing / reading objects to the
data file and i would like the driver program to be able to communicate
objects to each servlet. Can i do this w/ pipedinput / output streams? I do
not understand how i can reference a piped output stream in one object from
another!
TIA, Andrew.
|
| Author |
Message |
google
|
 Posted: 2003-7-15 20:59:00 |
Top |
java-programmer, JNI: call C-main program from Java
I have a C-program which calls Java functions through JNI.
The C-part runs okay, and I want to debug the Java code.
For that reason, I want to start the Java debugger and then start the
C-main program through JNI. After that I hope I can set
breakpoints within the Java part and start debugging.
In the documents I saw that "System.LoadLibrary()" can load
only DLL's and shared object, but no main-program.
Thanks for any help,
Josef
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Index ‹ java-programmer |
- Next
- 1
- AffineTransform.getScaleInstance questionHi,
I am using the AffineTransform.getScaleInstance to transform an image
by showing it growing. i.e. something like the following:
while(scale <= 1) {
repaint();
scale += 0.05;
try {
Thread.sleep(25);
}
catch(InterruptedException e) {
e.printStackTrace();
}
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setComposite(AlphaComposite.SrcAtop);
g2.transform(AffineTransform.getScaleInstance(scale, scale));
g2.fill(clipShape);
g2.dispose();
}
the problem is that the image grows large from the top lefthand corner
towards the bottom right hand corner.
What I want is the image to grow from the bottom left hand corner to
the top right hand corner.
I have tried messing with the Scale instance, but I cant seem to figure
it out.
anyone know how to do this? thanks!
- 2
- JSP, forward, include, dispatch rules ?Can I get a clear summary of the rules involved with these ?
forward, include, RequestDispatcher rd
<jsp:include page="servlet/MyServlet" flush="false" />
rd.forward(req, res);
<jsp:forward page="NextPart.jsp" />
response.sendRedirect("NewPage.html");
What I have seen, is that this Error occurs:
'IllegalStateException: Cannot forward after response has been
committed'
When a JSP/Servlet writes to the page using a PrintWriter and then
tries to do a forward.
Maybe the following also cause problems:
response.setContentType(...)
response.setHeader(...)
TIA for your help, suggestions; Please Advise.
- 3
- 4
- Doing one last thing to a WeakReferenceLew wrote:
> Paul J. Lucas wrote:
>> Lew wrote:
>>>
>>> This is not a flaw in Java.
>>
>> Yes it is.
>
> No, it isn't.
Real compelling argument there. Java programmers need to stop being in denial
and admit that Java has flaws just like every other language.
- Paul
- 5
- paintComponent into a BuffereImage?It seems like I should be able to override the paintComponent method of
a class and have it do its paint into a BufferedImage something like
this:
public void paintComponent(Graphics g) {
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics2D g2D = image.createGraphics();
super.paintComponent( g2D );
.. etc ...
But all I get is a null pointer exception on super.paintComponent( g2D
); even though g2D is definitely NOT null. The exception actually comes
deep in the bowels of Java at:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.awt.Rectangle.intersects(Unknown Source)
at javax.swing.text.BoxView.paint(Unknown Source)
at javax.swing.plaf.basic.BasicTextUI$RootView.paint(Unknown Source)
at javax.swing.plaf.basic.BasicTextUI.paintSafely(Unknown Source)
at javax.swing.plaf.basic.BasicTextUI.paint(Unknown Source)
at javax.swing.plaf.basic.BasicTextUI.update(Unknown Source)
at javax.swing.JComponent.paintComponent(Unknown Source)
at TextPanel.paintComponent(TestClass.java:139) <--- the
super.paintComonent()
Any ideas on how to make this work?
Thanks,
--gary
- 6
- 7
- McNealy should have watched "Godfather 3" -- "Never hate your enemies, it clouds your judgement.""The worst thing about this deal is that Sun brought it upon itself
through a campaign of ridicule and hate promulgated personally by CEO
Scott McNealy. This is McNealy's failure and nobody else's. The quotes
last week from McNealy were laughable, the about face nothing short of
shameful. How are Sun's big customers going to believe what the company
says in the future in the face of such a change? How can they base huge
technical investments on the word of Sun?"
Answer: They can't. They never could.
http://www.pbs.org/cringely/pulpit/pulpit20040408.html
- 8
- M-I 5-Persecution . my resp onse to the harass ment-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-= my response to the. harassment -=
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
My first reaction in 1990/91 was to assume that. if I broke contact then
they would not be able to follow and would lose interest.. So I did the
things that have been suggested by other people; I sold my. television,
stopped listening to the radio and tried. to withdraw away from the sources
of abuse as much as possible. I reasoned that. they must have more important
things. to deal with and that normal people would simply leave me alone if
it. were made difficult for them to continue their harassment.
I reckoned without the sheer vindictiveness of the abusers. They. did not
let up. but instead "got to" people around me, mainly people at work, to do
their dirty work for them. I went to see my GP, who refused to. believe what
he was being told, and. refused to direct me on to anyone who could be of
practical assistance. It was not until three. years had passed that the GP
admitted the matter was. outside his competence and suggested going to the
police.
In the summer of 1994 we called in. counter-surveillance experts from a
private detective agency to sweep our house and telephone for. bugging
devices. They conducted. a thorough search and found nothing; but as noted
above, since the existence of surveillance was being. forced in my face by
the harassers, you would expect. them to have taken the possibility of a
counter-surveillance sweep into account when. planning the type of devices
to. be employed.
In Easter 1995 I made a complaint to. my local Police station in London, but
the police have not expressed any intention to do anything about. the
continuing harassment ("we're not saying it's. happening and we're not
saying it isn't. happening" were the words used). I think the officer I
spoke to at Easter wasn't aware of it happening, although other members. of
the police force obviously do. know.
From April 1995 until the present time the. matter has been discussed in a
lot of detail on the Usenet (Internet) "uk.misc" newsgroup.. That discussion
has. given birth to the article which you are now reading. My hopes in
posting to Usenet were that. wider publicizing would discourage the security
services from continuing their harassment, and "draw. people out" into
concurring with the truth of what was being said. Neither of. those have
followed, but the discussion has served a purpose in allowing. this
structured. report to be created.
8322
- 9
- AES-RijndaelI am doing an entry in the Java glossary on AES aka
Rijndael symmetric cipher.
I wonder if anyone knows of opensource Java implementations.
see http://mindprod.com/jgloss/aes.html
for what I have discovered so far.
--
Canadian Mind Products, Roedy Green.
Coaching, problem solving, economical contract programming.
See http://mindprod.com/jgloss/jgloss.html for The Java Glossary.
- 10
- [Active Tags] Have the RefleX !hi,
People that are intersting in native XML programming can download the
RefleX engine freely here :
http://reflex.gforge.inria.fr
RefleX is available under the french license CeCILL, which is almost the
same as the well-known GNU GPL.
RefleX is a Java tool that allows people that have no particular
knowledge of Java to write smart programs entirely in XML ; however, the
most brave fellows could also design their own tags and plug them to the
engine ! Have a look at the "How-To" section to achieve this.
The concepts of native XML programming used in RefleX have been designed
separately, so that other implementations on other platforms/languages
can be considered.
Why programming in XML ?
At INRIA, we have experienced RefleX on a *real* operational project,
and it appears that :
-the code is very easy to produce
-the amount of code produced is very tiny
Despite the intrinsic verbosity of XML, the expressiveness of XPath
(which is used intensively in Active Tags) and the ability to declare
complex processes exposed as simple tags makes Active Tags programs very
efficient.
Active Tags has been designed like a programming language : it offers
several libraries (called modules) for different purpose : system
interactions, I/O, SQL, Web, etc and allow users to define simply their
own libraries, but Active Tags differs from other programming languages
in many ways... read more on the Active Tags website or on the RefleX
web site !
http://reflex.gforge.inria.fr
http://disc.inria.fr/perso/philippe.poulard/xml/active-tags/
You'll find on the RefleX web site some tutorials that are showing the
traditional "hello world" example, how to publish an entire XML
repository to HTML, how to map SQL to XML, how to design an MVC
architecture, and how to play with datatypes and PSVI ; most of them are
available in batch mode as well as in a Web application ready to run.
Don't say anymore that Santa Claus doesn't exists !
Enjoy !
--
Cordialement,
///
(. .)
-----ooO--(_)--Ooo-----
| Philippe Poulard |
-----------------------
- 11
- Java proxy server for IEHi,
I hope someone can help me (I am an inexperienced Java programmer).
What I'm trying to do is write a Java Application that acts as a proxy
server for Internet Explorer. The goal of the little Java application
is to be able to log HTTP requests and responses between IE and a web
server.
I've pasted my application as it exists so far. It only handles HTTP
GETs right now, which is fine for my purposes at the moment. It works
for simple HTML pages. The problem is that I can't get it to
read/write graphic information correctly, such as when a web page
requests a gif (the graphic appears messed up in IE). I have 2
questions for all the Java experts out there:
(1) How can I handle binary content so it's properly rendered in the
browser.
(2) Using writeBytes from the DataOuputStream class seems to write one
byte at time, even though I'm passing in a string. I'd like a method
that writes in batches to the socket endpoint. Is that possible?
Thanks for any and all help!
import java.io.*;
import java.net.*;
class SimpleProxy {
public static void main(String[] args) {
ServerSocket ss = null;
Socket s = null; // client socket connection with client (browser)
DataOutputStream os = null; //client (browser) output;
DataInputStream is = null; //client (browser) input
String sInput;
int iPosURLEnd;
String sURL;
Socket sServ = null; //client socket connection with server (web
server)
DataOutputStream osServ = null; //server (web server) output;
DataInputStream isServ = null; //client (web server) input
int iPosHostStart;
String sHost;
System.out.println ("Starting app...\r\n");
try {
ss = new ServerSocket(45678);
}
catch (Exception e) {
System.out.println ("Error establishing ServerSocket
connection.\r\n");
System.out.println ("Error: " + e.getMessage());
}
for (; ;) {
try {
s = ss.accept();
System.out.println("Connection established.\r\n");
os = new DataOutputStream(s.getOutputStream());
is = new DataInputStream(s.getInputStream());
}
catch (Exception e) {
System.out.println ("Error establishing connection.\r\n");
System.out.println ("Error: " + e.getMessage());
}
System.out.println("--------- Read REQUEST from client
--------\r\n");
for (; ;) {
try {
sInput = is.readLine();
if (sInput == null)
break;
System.out.println("Client: " + sInput);
if (sInput.startsWith("GET",0)) {
iPosURLEnd = sInput.indexOf(" ",4); // 4 = Len("GET ")
sURL = sInput.substring(4, iPosURLEnd);
iPosHostStart = sURL.indexOf("://") + 3; // 3 = Len("://")
sHost = sURL.substring(iPosHostStart,
sURL.indexOf("/",iPosHostStart+1));
try {
sServ = new Socket(sHost, 80); //assume port 80
osServ = new
DataOutputStream(sServ.getOutputStream());
isServ = new DataInputStream(sServ.getInputStream());
}
catch (Exception e) {
System.out.println ("Error establishing connection with
server.\r\n");
System.out.println ("Error: " + e.getMessage());
}
}
osServ.writeBytes(new String(sInput + "\r\n"));
if (sInput.compareTo("") == 0)
break;
}
catch (Exception e) {
System.out.println ("Error reading information from
client.\r\n");
System.out.println ("Error: " + e.getMessage());
}
}
System.out.println("--------- Write RESPONSE from server
--------\r\n");
for (; ;) {
try {
sInput = isServ.readLine();
if (sInput == null)
break;
System.out.println("Server: " + sInput);
os.writeBytes(new String(sInput + "\r\n"));
}
catch (Exception e) {
System.out.println ("Error reading information from
server.\r\n");
System.out.println ("Error: " + e.getMessage());
}
}
try {
isServ.close();
osServ.close();
sServ.close();
is.close();
os.close();
s.close();
}
catch (IOException e) {
System.out.println ("Error closing sockets.\r\n");
System.out.println ("Error: " + e.getMessage());
}
}
}
}
- 12
- Struts JDO EJB Hibernate JFC - NUTS !The industry is in pure and utter chaos.
So many choices. How does one know which one is the popular one?
Is it Struts? Is it JFC? Is EJB unpopular (bloat)?
Personally, I find that xdoclet makes writing EJB's a total breeze,
dealing with the database that is. Are people using JDO now, or have
people been looking to see what JDO is all about but can't find any
solid examples so that people can't get rolling with it?
For the webgui, I wish more solutions would take the XMLC (enhydra) or
Tapestry approach. JSP / JSF / Struts all fail to separate design
from content.
Which framework handles form processing best? When I tried Struts I
lost days and days dealing with the uninformative errors it spits out.
Which one is better? What do people like these days? Or is everyone
else also in disarray, and keeps browsing site after site after blog
after blog and can't seem to get the scoop anymore?
- 13
- memory profiler recommendationJavameisters,
I have written an application for J2SE using the Netbeans IDE. I would
like to test it for memory leaks before releasing it, and would like a
recommendation as to what to use. I tried OptimizeIt some time ago,
and it seemed to do what I want, but I was just wondering if there are
better (or less expensive) alternatives.
Thanks much,
Matthew Fleming
email***@***.com
(please remove X before using this address)
- 14
- 15
- Improving hashCode() to match equals()In my NamedBitField class I define equals() to mean that 2
NamedBitFields are equal if all 3 of their fields are equal.
Any suggestions for improving my hashCode() definition? I
can improve its performance by caching the computed hashCode
in a transient field, sure, but can I improve the _way_ it's
computed?
class NamedBitField {
String name; // name of bit field
int startIndex; // where it starts
int length; // how many bits it occupies
pubic boolean equals(Object obj) {
if (this == obj)
return true;
if ( obj == null || this.getClass() != obj.getClass() )
return false;
NamedBitField other = (NamedBitField) obj;
return
this.name.equals(other.name) &&
this.startIndex == other.startIndex &&
this.length == other.length;
}
public int hashCode() {
// to make this symmetric with equals() I'd prefer to
// involve all 3 fields (name, startIndex and length)
// in the computation of the hash. But how?
//
// Here I'm simply reusing String.hashCode(), but the
// hashed String at least incorporates the other
// fields
return ((name + startIndex) + length).hashCode();
}
}
Marco
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