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- 2
- Modify java AST before compilingHi !
I'm trying to modify an Abstract Syntax Tree (a
com.sun.tools.javac.tree.JCTree).
I can get the AST with something like that:
// new compiler, fileManager, compilationUnits1.....
CompilationTask ct = compiler.getTask(null, fileManager, null, null,
null, compilationUnits1);
JavacTask jt = (JavacTask)ct;
try {
Iterable trees = jt.parse();
//... do something else here....
} catch (IOException e) {
e.printStackTrace();
}
Then, I obviously can walk throw the tree....
I now want to modify this AST. Is there any simple way to achieve this
?
For example, if a leaf is a JCBlock, I would like to do something like
that (Just to test):
((JCBlock)t).stats.append(((JCBlock)t).getStatements().last());
but it seems that everything is read-only in those JCTrees.
Then, I would like to generate the .class with the modified tree... any
idea ?
Thank you !
Best regards,
Yohann Coppel.
- 2
- draw line position - networkingThe code bellow will enable users to scrible anything on a canvas. Now
what I intend to do is to create a vector object for every position
(pre_x,pre_y,x, y) of the lines drawn on the canvas and send it using
a socket connection to a remote server.
public void mouseDragged(MouseEvent e)
{
if(isButtonPressed==true)
{
pre_x=e.getX()+scrollbarH_value;
pre_y=e.getY()+scrollbarV_value;
isButtonPressed=false;
}
x=e.getX()+scrollbarH_value;
y=e.getY()+scrollbarV_value;
offscreenImageG.drawLine( pre_x, pre_y, x, y);
pre_x=x;
pre_y=y;
repaint();
e.consume();
message.setText(pre_x + ":" + pre_y + ":" + x + ":" + y);
}
Is my apporach considered to be feasible?. Any other ways?
Regards.
- 3
- the best way to store program setupHello,
What is the best way to store program configuration settings? Each
class has its own parameters that might be useful just for current
class. There are some parameters that might be useful in whole
program. Probably main class could have confifiguration for whole
program, but how I could access them from class that is inside main
class?
Thank you
- 3
- Where in the language is ".class"?Where in the Java language specification or API is the idiom
"Foo.class" defined? It's not an attribute of any class I can find,
and I can't find it in the core language specification.
Thanks.
- 3
- card shuffling errorI am relatively new to java programming and I am working on a card
project for school. I had finished and tested every method with error
in my Deck class. However, in the time it took to pick up dinner it is
now producing errors. I would greatly appreciate anyone input and help.
This is the error that is produce when invoking the shuffle method.
java.lang.IndexOutOfBoundsException: Index: 235, Size: 51
at java.util.ArrayList.RangeCheck(ArrayList.java:546)
at java.util.ArrayList.get(ArrayList.java:321)
at Deck.swap(Deck.java:176)
at Deck.shuffle(Deck.java:129)
public class Deck
{
/** The number of cards in a deck */
public static final int DECK_SIZE = 52;
/** The number of times to shuffle */
public static final int TIMES_TO_SHUFFLE = 1000;
private ArrayList deck; // a deck of cards
/**
* Constructor for objects of class Deck
*/
public Deck()
{
deck = new ArrayList();
newDeck();
}
/**
* Load a new deck with all DECK_SIZE cards
*/
public void newDeck()
{
if (deck.size() > 0){
deck = null;
}
else{
//Hearts
deck.add(new Card("Ace","Hearts",11));
deck.add(new Card("Two","Hearts",2));
deck.add(new Card("Three","Hearts",3));
deck.add(new Card("Four","Hearts",4));
deck.add(new Card("Five","Hearts",5));
deck.add(new Card("Six","Hearts",6));
deck.add(new Card("Seven","Hearts",7));
deck.add(new Card("Eight","Hearts",8));
deck.add(new Card("Nine","Hearts",9));
deck.add(new Card("Ten","Hearts",10));
deck.add(new Card("Jack","Hearts",10));
deck.add(new Card("Queen","Hearts",10));
deck.add(new Card("King","Hearts",10));
//Diamonds
deck.add(new Card("Ace","Diamonds",11));
deck.add(new Card("Two","Diamonds",2));
deck.add(new Card("Three","Diamonds",3));
deck.add(new Card("Four","Diamonds",4));
deck.add(new Card("Five","Diamonds",5));
deck.add(new Card("Six","Diamonds",6));
deck.add(new Card("Seven","Diamonds",7));
deck.add(new Card("Eight","Diamonds",8));
deck.add(new Card("Nine","Diamonds",9));
deck.add(new Card("Ten","Diamonds",10));
deck.add(new Card("Jack","Diamomds",10));
deck.add(new Card("Queen","Diamonds",10));
deck.add(new Card("King","Diamonds",10));
//Spades
deck.add(new Card("Ace","Spades",11));
deck.add(new Card("Two","Spades",2));
deck.add(new Card("Three","Spades",3));
deck.add(new Card("Four","Spades",4));
deck.add(new Card("Five","Spades",5));
deck.add(new Card("Six","Spades",6));
deck.add(new Card("Seven","Spades",7));
deck.add(new Card("Eight","Spades",8));
deck.add(new Card("Nine","Spades",9));
deck.add(new Card("Ten","Spades",10));
deck.add(new Card("Jack","Spades",10));
deck.add(new Card("Queen","Spades",10));
deck.add(new Card("King","Spades",10));
//Clubs
deck.add(new Card("Ace","Clubs",11));
deck.add(new Card("Two","Clubs",2));
deck.add(new Card("Three","Clubs",3));
deck.add(new Card("Four","Clubs",4));
deck.add(new Card("Five","Clubs",5));
deck.add(new Card("Six","Clubs",6));
deck.add(new Card("Seven","Clubs",7));
deck.add(new Card("Eight","Clubs",8));
deck.add(new Card("Nine","Clubs",9));
deck.add(new Card("Ten","Clubs",10));
deck.add(new Card("Jack","Clubs",10));
deck.add(new Card("Queen","Clubs",10));
deck.add(new Card("King","Clubs",10));
}
}
/**
* Add a single card to the deck.
* @param a Card object
*/
public void addCard(Card newCard)
{
// add a card to the deck
deck.add(newCard);
}
/**
* Shuffle the deck. This involves selecting random pairs of
* cards and swapping them, the number of times to swap determined
* by the constant TIMES_TO_SHUFFLE.
*/
public void shuffle()
{
//Zero the deck vector
deck.removeAllElements();
int index1 ,index2;
for (int i = 0; i < DECK_SIZE ; i++) {
index1 = (int)(Math.random()*TIMES_TO_SHUFFLE);
index2 = (int)(Math.random()*TIMES_TO_SHUFFLE);
swap (index1, index2);
}
}
/**
* Display the entire contents of the deck. Not used in the
* game but useful for debugging.
*/
public void showDeck()
{
Iterator it = deck.iterator();
while(it.hasNext()) {
Card currentCard = (Card) it.next();
System.out.println(currentCard);
}
}
/**
* Remove the top card from the deck.
* @return the Card object removed or null if there is nothing in
the deck.
*/
public Card takeCard()
{
int index = 0;
if (index >= deckSize()) {
return null;
}
else{
return (Card) deck.remove(0);
}
}
/**
* Return size of deck
*/
public int deckSize()
{
return deck.size();
}
/**
* Card Swap method
*/
public void swap(int index1, int index2) {
Card temp = (Card)deck.get(index1);
deck.set(index1, deck.get(index2));
deck.set(index2, temp);
}
/**
* Methods returns card index and card description - testing
purpose
*/
public void displayCardIndex()
{
for (int index = 0; index < deckSize(); index++)
{
System.out.println("Index: " + index + " Card : " +
deck.get(index));
}
}
}
- 3
- Filechooser appearanceI am using Netbeans. I need a JFileChooser to pop up in it's own
window, but i'm not sure how to make this happen. i'm new to java gui
programming. could someone please point me in the direction of (or
just provide) a clear-cut example of how to do this, as I can' seem to
find one?
- 5
- Java application for GPRS connectionI need to manage the GPRS connection (set up the connection, connect
and disconnect) in a symbol handheld device with Windows Mobile 5. I'm
developing this application with Java 1.3 and using IBM J9 as jvm. How
can I deal with this?
Many Thanks
- 5
- IO ExceptionHi,
I have a Java application which takes in either the server name or IP
address, domain name, user name and password, and copies the files
from the specified server directory to the local C drive.
It works perfectly fine when I run this on my local m/c and I can use
either the server name or the server IP address.
But when I move the jar file to a different workstation and execute it
I get an IO exception - 'Source file does not exist' when I specify
the server using its IP address. It still works on a different
workstation when I pass the server name.
Any clue as to why should it happen?
Thanks,
Beena
- 9
- Java Print Service and WindowsIs there a way to print simple text using the Java Print Service under
Windows? The target printer is a high speed dot matrix printer that
does not support graphics. This works without any problems under Linux,
but no matter what printer driver is installed on a Win2K machine, JPS
fails to locate a print service for DocFlavor.READER.TEXT_PLAIN (or any
DocFlavor.*.TEXT_*).
Any ideas?
- 9
- Handling of DST in javaHi,
Does java handle DST automatically ?
I'm using java Gregorian calendar to get the time/date. Does this
automatically give the local time/date iirrespective of DST or special
handling should be done ?
- 11
- benchmarks? java vs .netJon Skeet [C# MVP] wrote:
> On Jun 3, 4:39 pm, Jon Harrop <email***@***.com> wrote:
>> FWIW, F#/Mono is 3x slower than F#/.NET on the SciMark2 benchmark. I'd like
>> to know how performance compares between these platforms for parallel code.
>
> If Razii is genuinely comparing Java with Mono (I haven't looked at
> any of the figures) it's a silly test to start with (unless you're
> specifically interested in Mono, of course). The vast majority of C#
> code runs on .NET rather than Mono - and while I applaud the Mono
> team's work, I seriously doubt that it has quite has much effort going
> into it as Microsoft is putting into .NET. I'd expect .NET to
> outperform Mono, and on microbencharks like these the difference could
> be quite significant in some cases.
I have frequently seen a x2 factor between MS .NET 2.0 and Mono 1.2 !
Comparing with Mono is too easy.
Arne
- 13
- Did anyone upload file to php server by using swing applet before? Need help!!!Hi,
I need a help. Recently I wrote a swing applet for uploading files to
php server. It seems that everything is fine now. I can get the exactly
same size files in the server. For text file, there is no any problem
to be openned. But for image and moive files (such as .jpeg, .gif .mov
and etc.), those files can not be openned after they are uploaded to
sever even the size is exactly the same as orignal files.
I think that it should be caused by "Content-Type".
For testing, I change my Content-Type to "image/gif" to send gif files.
However, the problem is still there. Now, I have no idea about this
problem. Could any one give me a favor? Thanks in advance!!!
I attached the code related to connection and sending data here for
your review.
public boolean upload() throws Exception{
boolean done = false;
String file_name = file.getName();
String file_data = readFile();
StringBuffer response = new StringBuffer("");
OutputStream os = null;
BufferedReader in = null;
HttpURLConnection conn = null;
try{
URL serverURL = new URL(url);
// connect to server
URLConnection uc = serverURL.openConnection();
conn = (HttpURLConnection) uc;
conn.setAllowUserInteraction(true);
conn.setInstanceFollowRedirects(true);
// set connection as POST
conn.setRequestMethod("POST");
conn.setDoOutput(true); // turns it into a post
// setup headers
conn.setRequestProperty(
"Content-Type",
"multipart/form-data; boundary=" + CONTENT_BOUNDARY);
conn.setRequestProperty("Accept-Language", "en-us");
conn.setRequestProperty("Accept-Encoding", "gzip, deflate");
conn.setRequestProperty("CACHE-CONTROL", "no-cache");
os = conn.getOutputStream();
String request =
"--"
+ CONTENT_BOUNDARY
+ "\r\n"
+ "Content-Disposition: form-data; name=\"upfile\"\r\n\r\n"
+ file_name
+ "\r\n"
+ "--"
+ CONTENT_BOUNDARY
+ "\r\n"
+ "Content-Disposition: form-data; name=\"upfile\"; filename=" +
file_name
+ "\r\nContent-Type: multipart/form-data\r\n\r\n"
+ file_data //file is read into a string here, is it OK? But no
other choose.
+ "\r\n"
+ "--"
+ CONTENT_BOUNDARY
+ "\r\n";
System.out.println("DEBUG: Sending the following request:\n\r" +
request);
System.out.println("DEBUG: Sending the post request...\n\r");
os.flush();
os.write(request.getBytes(), 0, request.getBytes().length);
os.flush();
in = new BufferedReader(new
InputStreamReader(conn.getInputStream()));
String inputLine;
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
// closing connections
in.close();
in = null;
os.close();
os = null;
conn.disconnect();
conn = null;
done = true;
- 13
- Another exception handling question
public void myMethod (String name){
if(!condition1){
throw new IllegalArgumentException("A message ");
}
if(!condition2){
throw new IllegalArgumentException("Another mesage");
}
}
When I call myMethod I want to distinguish between the different
reasons for the same exception. Is it better to make my own
exception ? What is my good practice?
cheers,
//mike
- 14
- googling google persistance using google apiI've been over to <http://www.google.com/apis/> and downloaded
GoogleAPIDemo.java, which is much simpler than expected. I'd like to
save the query results to a file. I'm thinking that each query result
could almost be apended to an XML file, this seems the most natural and
easiest approach.
However, I'm, err, not finding anything on google about doing so. I
know that the demo uses SOAP and I know that I know nothing about SOAP
and have no real interest in learning about SOAP at this time.
However, I believe that SOAP is good for communicating with databases,
yes?
I've been over to <http://www.w3.org/TR/soap/> which led me to:
Abstract
SOAP is a lightweight protocol for exchange of information in a
decentralized, distributed environment. It is an XML based protocol
that consists of three parts: an envelope that defines a framework for
describing what is in a message and how to process it, a set of
encoding rules for expressing instances of application-defined
datatypes, and a convention for representing remote procedure calls and
responses. SOAP can potentially be used in combination with a variety
of other protocols; however, the only bindings defined in this document
describe how to use SOAP in combination with HTTP and HTTP Extension
Framework.
which all sounds very nice but it seems like I'd have to buy a book to
get it working. There's lightweight, then there's lightweight, if you
get my meaning, and I think that SOAP is bit not-lightweight for my
purposes. I would like an XML file with something like (please forgive
my atrocious XML):
<result>
<www.whatever.com />
<some text here />
</result>
<result>
<www.foo.com />
<different text here />
</result>
<result>
<www.bar.com />
<text on bar here />
<result>
Or something along those lines, which mirrors whatever google gives the
demo. However, I can't find something ready-made for creating such a
file, which surprises me. I'm looking for something relatively easy
which I can put together with the demo to save some results to file,
such that the results can be put into a database at a later time.
However, my google results are less than stellar. How do people
save/persist their google results?
My personal computer is broken at the moment, so this all hypothetical.
I haven't compiled the demo yet, never mind modifying it.
thanks,
Thufir
- 16
- JspException in custom tagHello,
Can someone show me the error of my ways.....
I have a custom tag 'public int doStartTag() throws JspException' from
which a JspException is thrown. The exception is forwarded to an JSP
error page and from there I want to (eventually) shove the contents of
the exception into a javabean.
My javabean is set up as follows:
public class errorBean
{
Throwable errorObject = null;
String errorMessage = null;
public void setErrorObject(Throwable errorObject)
{
this.errorObject = errorObject;
errorMessage = errorObject.getMessage();
}
public String getErrorMessage()
{
return errorMessage;
}
} //errorBean
My JSP error page looks like:
<%@ page isErrorPage="true" %>
<html>
<body>
<jsp:useBean id="errorBean" class="errorBean"/>
<jsp:setProperty name="errorBean" property="errorObject"
value="${pageContext.errorData.throwable}"/>
The error message is <jsp:getProperty name="errorBean"
property="errorMessage"/>
</body>
</html>
When I throw an exception like 'throw new JspException("Hello World")'
in my custom tag,
everything seems to work i.e. "Hello World" shows up in my Mozilla &
Netscape browser.
When I throw an exception like 'throw new JsPException("Hello
World",throwableObject)
where throwableObject subclasses Throwable, I get a 'http status 500'
error, but the browser clearly displays as part of a stack trace (?)
the exception "Hello World" as well as the root cause.
Why would this work in one case ('throw new JspException("Hello
World")' and other
('throw new JsPException("Hello World",throwableObject)) fail to
display "Hello World"?
Thnaks for any help.
|
| Author |
Message |
Flex
|
 Posted: 2005-1-5 16:59:00 |
Top |
java-programmer, MQ, JNDI and Multicast socket
If I use MessageQueue with JNDI, to send a package to all hosts I
had to use multicast socket or other ?
--
Hi Flex
|
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Index ‹ java-programmer |
- Next
- 1
- Need help creating a program to create sudukoStill a little rough at this language but i need to create a program
for my class. Was wanting to create a java program that makes sudukos.
It doesn't need a GUI or anything like that just ouput to a txt file
ot to the screen. I would appreciate any help or direction.
- 2
- Question on the flush methodAccording to Sun's web site, the flush method of the OutputStream object
does nothing.
So, what does actually happens when you call it?
At times I may see different behavior when including it within a program
(some times a socket read error) which I would think is strange esspecially
if the method is not supposed to do anything.
Any ideas?
- 3
- thin java cient?Hello, please, I'm searching for a Thin Java Client, for J2EE.
I want to build a thin java swing client.
How to do it?
tks
Programador
----------------------------------
email***@***.com
- 4
- 5
- Java securityI havean applet that connects to Oracle osing the thin client. It
works when run from IDE. When I try to load it into a web browser I
get
java.security.AccessControlException: access denied
(java.util.PropertyPermission oracle.jserver.version read)
What's up?
- 6
- XML call XSL that calls xml through document() elementHello,
I am trying to create an XML document on the fly that sends some
parameters to an xsl document which calls the correct xml document that
corresponds to the parameters.
I reference the xsl document:
<?xml version="1.0" encoding="ISO-8859-1"?>
<?xml-stylesheet type="text/xsl" href="web-primary.xsl"?>
I am just trying to hardcode the request to prove that this is possible
for the time being so the parameters are already in the xsl that will
eventually be variables.
but I am unsure what else to include in the first XML file to make the
call to the web-primary.xsl????? My XSL is complete and the
corresponding XSL files are complete.
The xsl doc has a document element that calls the correct xml file that
contains the data.
My reason for doing all of this is because Firefox will not allow me to
go to a remote xml file from the server so I want the browser to do the
work of getting the remote xml file. If you have a better way of doing
this, please let me know.
thx.
- 7
- Array of generic List?Hello,
I am new to 1.5 and thus generics. I have read the generic tutorial and
a decent number of websites/newsgroup posts on the subject. But I still
cannot find a satisfactory solution to the following (as of now the
best I've got is an unchecked conversion warning)
The code below does not compile, but I think it shows to a human what I
want to accomplish. I can't seem to find the proper syntax and use of
generics to accomplish this without a warning. Any help and reasoning
why I need to do whatever the solution is would be great. Thanks.
public class MyClass {
private List<Foo>[] myFoos;
public MyClass() {
myFoos = new List<Foo>[5];
}
public void addFoo(int index, Foo foo) {
myFoos[index].add(foo);
}
}
- 8
- Java server performance - jeetyHi All,
I am working on an application where a servlet need to handle min 600
request / sec(which will keep on increasing in future)
So I am not able to decide which application server I should use.
As I go through some benchmarks I came to know that Jetty's performance
is better but
I don't know how much load it can handle.
Is there any who has used Jetty on heavy traffic application?
or is there any another servlet container / HTTP Server which can
handle such a load
Plz suggest me.
Thanks in Advance.
Rajiv Girdhar
- 9
- Novice Form QuestionI am a novice at JSP / HTML and have a Forms releated question. I am
really looking for sample code I can leverage to help understand how
to address non-trivial form layouts.
I undestand the how to build a -simple- form with a few input fields
and process this with JSP - Struts interaction. Unfortunately, I am
weak in HTML / JavaScript and I need to understand and build a more
complicated form.
Basically my form must look something like this:
User Name: _________________ Baggage Type ____________
Add Button | Remove Button Add Button | Remove Button
---------------------------- -------------------------
| Tom | | SomeBagType 1 |
| Dick | | SomeBagType 2 |
| Harry | | SomeBagType 3 |
| Jane | | SomeBagType 4 |
| | | |
---------------------------- -------------------------
Submit Button Cancel Button
Note that there are 6 buttons on the form. The Add / Remove buttons
are intended to allow the user to Add or Remove -User name's- or
-Baggage Type's- before the form is submitted.
I am not sure how to handle this. My guess is that Javascript might
work ( I do Java but not JavaScript :-( ) but I am open to suggestions
and most importantly EXAMPLES of how this might be implemented.
This code will part of a JSP-Struts project.
Thanks.
- 10
- 11
- internet address vs lanI am about to create a RPC program and I need a servlet to talk to a
server. The servlet is running on the internet, the server is running
on a lan computer. I am pretty sure that the lan ip address is behind
our firewall. Can I still communicate with the server through RPC.
Berlin Brown
email***@***.com
this question sounds confusing, doesnt it?
- 12
- 13
- Help with writing simple parser for HTML/XMLI'm having trouble getting started with coding a simple parser and prototype
for my application.
The parser needs to parse HTML & XML pages to strip the tags and return just
the data. Ive read thru sevral java refeerence books but seem to be having
trouble getting started with the code.
I'd be gratefull for a push in the right direction.
thanks
sal
ps this is my final year University Computer Science project
for more details on the project
http://www.mellowmoose.org/project.html
- 14
- Saving canvasHi. I have a problem with saving canvas to file. All over net there
are faqs on how to save a NEW canvas to file (after drawing on it). I
have a canvas, what should i do in order to save what's currently on
it to a file?
- 15
- Anyone seen this problemMaybe I am being stupid, but I am having difficulty getting mouse events
from a custom JComponent. At this point I have put an instance of a subclass
of JComponent in a JScrollPane and placed it in the center of a
BorderLayout. I then added a mouse listener to the subclass of JComponent,
traced through the code to make sure I am acutally adding the listener, but
my mouseClicked(), mousePressed() and mouseReleased() methods on my listener
class are not called. Any one seen this problem before.
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