Java NIO Platform Specific Quirks & Solutions

I have been working with the NIO library recently, and I was disapointed to find that there are many little platform specific quirks. It is hard to design a program that can handle diffrent platforms when you have to do switches to handle the many little quirks. While I have only found 2, I suspect there are more. I invite others to post about NIO quirks and a possible solution if one is known.
Quirk #1:
On Win98, the a key is only readable once the first time the key is writable, while on WinXP, the key is flagged writable every time it is writable.
Proposed Solution:
Design a program which only expects the key to writable once on connection, and forget about other calls (since they cannot be expected on every OS)???
Quirk #2:
(Note: check out the topic NIO Non-Blocking Server not Reading from Key (http://forum.java.sun.com/thread.jsp?forum=31&thread=327241) for more info...)
On WinXP, a key which is registered both OP_READ and OP_WRITE doesnt flag any read requests, even if input does come to the server.
Possible Solution:
See other fourm for details.

Also... I dont have a Linux dev-box to test this stuff on... If anyone runs into things relating to the above quirks on OS's not mentioned, please post the os, and how the quirk is handled.

Similar Messages

Java NIO Vs Normal IO

hi ppl...i want to know when v should prefer nio over normal io. I read somewhere that only if you have to deal with a lot of connections simultaneously you should consider using NIO. as an example it said that a web spider which needs to process a few million connections simultaneously NIO should be preferred. Now in my project i need to have around 750 simultaneous connections. Should i use NIO or traditional IO ?

There is not enough information given about the
specifics of this situation to be making such broad
claim that it will help.I got enougth information. NIO was introduced because traditional Java I/O was found lacking. Traditional I/O is good for reading and writing a few files but that's not what the OP will be attempting. From the NIO proposal documentation:
2.3 What needs of the Java community will be addressed by the proposed specification?
* The proposed specification will satisfy several long-standing needs of the Java community.
* The scalable I/O API will make it easier to write production-quality web and application servers that scale well to thousands of open connections and can easily take advantage of multiple processors;
* The fast buffered binary I/O API will make it easier to write high-performance, I/O-intensive programs that manipulate streams or files of binary data;
* The fast buffered character I/O API will simplify the efficient handling of character streams and files; it will also bring regular expressions and a compact notation for formatted output to the Java platform, putting it on a par with other popular platforms such as Perl;
* The character-set converter API will give developers direct access the platform's built-in character-set converters and will also provide for the easy "plugging in" of new converters;
* The new set of I/O exceptions will make it easier to write programs that recover from different types of I/O failures in different ways, and to write user interfaces that behave consistently on different platforms when I/O failures occur; and
* The new filesystem interface will work more consistently across platforms, will make it easier to write programs that gracefully handle the failure of filesystem operations, will provide more efficient access to a larger set of file attributes, will allow developers of sophisticated applications to take advantage of platform-specific features when absolutely necessary, and will allow support for non-native filesystems, such as network filesystems, to be "plugged in" to the platform.
2.4 Why aren't these needs met by existing specifications?
Some of the above needs can be met by using existing APIs together with a significant amount of custom code. It is possible, for example, to write a class that implements the DataInput interface and runs about eight times faster than the built-in DataInputStream class. The Java community would be better served if the Java platform made this sort of work unnecessary.
Some of the above needs can be met by using existing APIs in fragile, implementation-specific ways. To recover from specific types of I/O errors, for example, developers sometimes write code that dissects the message strings of generic IOException objects. This technique may work with a particular implementation of Java on a particular operating system, but it is not very portable. A different implementation on a different operating system may, in a given situation, throw an IOException object with a completely different message string.
Finally, most of the above needs cannot be met simply because the required functionality is not provided by the current I/O APIs.
In summary. If you're doing serious I/O (like 1000 open connections) go for NIO. It's also easier to start with NIO right away to get used to it than it is to first use traditional I/O only to find you need to upgrade later on.

Problematic frame: # J java.nio.MappedByteBuffer.load()

Helo all...
I'm getting an error when generating a PDF using BIRT Framework in Eclipse. Nothing fancy, just compiling a simple report to pdf.
The problem is, the JVM crashes with the following error:
# A fatal error has been detected by the Java Runtime Environment:
# EXCEPTION_IN_PAGE_ERROR (0xc0000006) at pc=0x0190f0be, pid=5848, tid=2392
# JRE version: 7.0_09-b05
# Java VM: Java HotSpot(TM) Client VM (23.5-b02 mixed mode, sharing windows-x86 )
**# Problematic frame:
# J java.nio.MappedByteBuffer.load()Ljava/nio/MappedByteBuffer;**
# Failed to write core dump. Minidumps are not enabled by default on client versions of Windows
# An error report file with more information is saved as:
# C:\Users\luis\Desktop\teste\birt\hs_err_pid5848.log
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/bugreport/crash.jsp
I already tried:
1. Run the program in another computers - it worked
2. Reinstall Java on the computer - It did nothing
3. I check the integrity of the disk C: - Nothing
I already spent two days trying to fix this and I don't have any progress. I can't find a solution on the web either.
Thanks in advance

Thanks for the help.
But it can not be related to BIRT because it works in every other computer that I tried so far. There is only one computer that not works properly.
If it were BIRT's fault, it wouldn't work in any computer.
Thanks again

I have windows 7 64bit. When i installed firefox and then java, i do not have java tm platform or any java plugin. I can't watch free movie's online!!

As i told i have Windows 7 Ultimate 64bit version. I install java and have problems with Java Deployment Toolkit and Java(TM) Platform SE. It won't show in add-on. I cant watch movies. When I play movie it says java is missing but when I use IE I can watch some movies. I try reinstaling Java and even reinstall Windows. But problem was still there. I run java check (from Firefox) to see if java is installed and it confrmed. I even try diferent versions of Java and Mozilla. I even use JDK and JRE. I install java for 64bit and mozilla is also for 64bit version of system.
I have another laptop with 32 bit version and everything works great. Installation procedure was same (only used 32bit versions of softwares).
When I go to control panel and java options (windows 64bit) enable java content in your browser is marked. But in advanced tab default java for browser (mozilla family) is unmarked. And when I mark box and leave (apply then ok) and return box is empty. It wont confirm. In 32bit version of laptop i have alsou java plugin but in 64 bit it is not there. Here is a picture what I was talking about. This is on windows 32 bit for 64bit is some just box for mozilla family is empty and under that java plugin do not exist.
[code]http://s23.postimg.org/dl4dun4p7/Untitled.jpg[/code]
hope someone have solution!!

you don't have to reinstall firefox or java, you can just download and install the 32bit-java next to your currently installed java version. it should then be picked up by firefox and be displayed under firefox > addons > plugins...

Java ME Platform SDK - S60 Emulator Problem

Hi Everyone!
I am new to S60 development. I searched the forum, and some other discussion forums but could not find any solution to my problem (If there is one in this forum, sorry about that).
I installed Java ME Platform SDK 3.0 Early Access. I also installed Java SDK for S60-FP1, and added this platform to my IDE with no problems.
The problem is, I can write and execute my code on S60 emulator, but Java IDE has got this annoying exception blinking on the bottom right side saying: "java.lang.IllegalArgumentException: Device S60Emulator not registered!". As I said, I can run the application, but I cannot debug because of some exceptions!
Why this can be happening, can it be a misconfiguration or something?
Thank you all!

Did you check Release Notes of the SDK? I've seen it once - if memory serves it lists quite a lot of known bugs.
Maybe the problem you describe is listed there too... and if you're really lucky then description may even mention some workaround for it.

Java NIO locking and NTFS network resources

Hi all - just ran into a really nasty situation and I was wondering if anyone else has hit it and might have some suggestions.
Platform: JRE 1.4_02 on a Win XP machine
The following test code locks a file, then copies it to another location using NIO.
When I run it with source path on my local drives (C), it works fine. If I run it with source path on a network shared resource, it fails with an IOException with description 'Error performing inpage operation'.
If I disable the lock immediately before the copy operation, it works fine.
My conclusion is that there is something about the NIO locking implementation that prevents it from working properly with NTFS volumes on other hosts. Can this be right? I've found the following bug report:
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4774175
but this seems like a huge problem that would prevent folks from using NIO in many, many applications. Maybe I'm wrong on something here...
Anyway, here's the test code:
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.channels.FileChannel;
import java.nio.channels.FileLock;
* Created on May 28, 2004
* (c) 2004 Trumpet, Inc.
* @author kevin
public class test {
     private void createFile(File f) throws IOException{
          FileOutputStream os = new FileOutputStream(f);
          for(int i = 0; i < 10; i++){
               os.write(i);
          os.close();
     public test() {
          boolean testWithReleasingLockPriorToCopy = false;
          final File f1= new File("w:/temp/test2.lok");
          final File f2 = new File("w:/temp/test.lok");
          f1.delete();
          f2.delete();
          try {
               createFile(f1);
               RandomAccessFile raf1 = new RandomAccessFile(f1, "rw");
               RandomAccessFile raf2 = new RandomAccessFile(f1, "rw");
               FileChannel ch1 = raf1.getChannel();
               FileChannel ch2 = raf2.getChannel();
               FileLock flock1 = ch1.lock();
              if (!f2.getParentFile().exists() && !f2.getParentFile().mkdirs())
                   throw new IOException("Unable to create directories for destination file '" + f2 + "'");
              if (testWithReleasingLockPriorToCopy)
                   flock1.release();
               ch1.transferTo(0, raf1.length(), ch2);
               raf1.close();
               raf2.close();
          } catch (Exception e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
     public static void main(String[] args) {
          test t = new test();
}Does anyone have any pointers here? I need to be able to exclusively lock a file on a network drive (preventing any other applications from opening it), then make a copy of it. I can't use regular stream operations, because the lock prevents them from working properly (it appears that, once you grab a file lock using NIO, the only way your application can use the file is via the NIO operations - using stream operations fails...).
Thanks in advance for any help!
- Kevin

i've run into the same problem recently, channels working fine for local file locking, but when you turn to the network, they fail to accurately handle locks.
i ended up writing a jni utility to ship with my java application that locks files using native windows calls.
my .c file ends up looking something like this:
JNIEXPORT jint JNICALL Java_Mapper_NativeUtils_LockFile
(JNIEnv *env, jobject obj, jstring filename)
const char* ntvFilename = (*env)->GetStringUTFChars(env, filename, 0);
int retVal = (int)CreateFile
ntvFilename
, GENERIC_WRITE
, FILE_SHARE_READ
, 0
, OPEN_EXISTING
, FILE_FLAG_SEQUENTIAL_SCAN
, 0
//add code to throw java exceptions based on retVal
if (retVal == (int)INVALID_HANDLE_VALUE)
return retVal;
(*env)->ReleaseStringUTFChars(env, filename, ntvFilename);
return retVal;
JNIEXPORT jboolean JNICALL Java_Mapper_NativeUtils_UnlockFile
(JNIEnv *env, jobject obj, jint handle)
     CloseHandle((void *)handle);
return 1;
it's a little shy on the error checking side, but it provides support for network file locking that java seems to lack.

How do I search the downloaded Java? Platform, Standard Edition 6 API?

I am a newbie to Java (I had done some limited programming in C ++ years ago). I have downloaded the Java? Platform, Standard Edition 6 API Specification, and can view this in my Firefox browser. How can I search to certain classes in this documentation easily? For instance, if I want to ding out all of the operations available for String or System.out, etc, , is there a way that I can type in System.out, or String somewhere, and get a list of what is available?
Thanks

Brian_Rohan wrote:
Here is the code that I compiled and it worked:Yeah, "args" there isn't part of the API. It's the name of the variable that is the first parameter to the main method defined there.
The stuff between the parentheses is a list of declarations of local variables that form the parameter list to that method, to put it technically.
The thing that's part of the API is the class String. In "String[] args", the bit on the left is the type of the variable, and the bit on the right is name of the variable. A name of something you define like that wouldn't be in the API. However, the name of the class String is.
If you look at the import statements, you'll see if the name "String" is actually shorthand for a class defined elsewhere. There's this:
import java.util.*;So you can know that "String" is either defined in the java.util package, in the "helloworld" package (which also wouldn't be in the API because you're defining in there using the package keyword), or in java.lang. (The "java.lang" package is automatically imported.)
You could look in the API docs for java.util.String or java.lang.String to find the class definition. But I'll save you the time by letting you know that it's actually java.lang.String.
Again I am new at this, what would args.length be?You'll see that the type of the "args" variable is "String[]". That means that it's an array of String objects. (The [] means arrays.) Arrays all have a field called "length". This also is part of the language, not the API, so it would be in a language guide, not the API.
The value of args.length would depend on how you ran your program. When you run a program on the command line like this:
java HelloWorldor this:
java HelloWorld foo bar bazThe java virtual machine takes all the things after the class name and sticks them in an array of String. Then it looks for a static method named "main" in the HelloWorld class, and passes it that array. So in the first case above, args.length would be zero, and in the second case it would be three.
By the way, when you post code, please wrap it in code tags. Highlight it, then click the "CODE" button above the text input box.
Edited by: paulcw on Nov 4, 2009 6:35 PM

LiveCycle Workbench ES2 - "Java(TM) Platform SE binary has stopped working" Error

Hi,
I am getting this error when I try to create a new process o open an existing process.
"Java(TM) Platform SE binary has stopped working"
The only option is to click on a "Close" button and end the LC Workbench ES2 program.
Also, when I try to open an existing form, it displays 'garbage' - a screenfull of control unrecognizable characters - instead of the form itself.
When this error comes up, I also get a pop-up window with a list of log entries / errors (please see attached: Java Platform SE binary has stopped working.jpg)
Environment:
Windows Vista Ultimate running on HP Desktop (e9107c Intel CORE 2 Quad Processor withy 8 GB RAM, 750GB HDD)
Downloaded and installed the Trial Version of LiveCycle ES2 package (Windows JBoss version)
The LiveCycle ES2 server is installed properly and is working with the following services. Are there any missing services?
LiveCycle Output ES2, LiveCycle Rights Management ES2, LiveCycle PDF Generator ES2 Evaluation, LiveCycle Process Management ES2, LiveCycle Workspace ES2, Applications and Services, LiveCycle ContentServices ES2, LiveCycle Forms ES2
I already had Adobe Acrobat Pro Extended 9.2 and the associated LiveCycle Designer instaleld prior to installing the Trial of LC ES2.
Basesd on the installation insttructions, I deleted the Designer ES from my Acrobat Pro Extended and instaleld the LC Workbench ES2.
Now I don't see a seprate entry for the LC Designer ES2 anymore on my Start >> Programs.
And th newly installed LC Workbench is not working
Any help in making the workbench 'work' is greatly appreciated.
Are there any tests we can do to troubleshoot this?
Thanks.

Here is some additional information that may be helpful in identifying the cause for this problem.
Here is the Exact ERROR :
Java (TM) Platform SE binary has stopped working
A problem caused the program to stop working correctly.
Windows will close the program and notify you if a solution is available.
Button: "Close Program".
On clicking that button, the error window goes away; the main LC WB ES2 program also closes; but a long error window appears. The full screenshot was attached in my original message. The top few lines are reproduced below.
JVMterminated. Exit code=255
C:\Program Files (x86)\Adobe\AdobeLiveCycleWorkbench ES2\workbench\jre\javaw.exe
-Xms128m
-Xmx512m
-XX:PermSize=256m
-XX:MinHeapFreeRatio=40
========Here is teh cutrrent status ===================
Adobe LiveCycle Designer ES2 is working properly: Good
Adobe LiveCycle Workbench ES2 has ONE problem
1. Program Starts properly
2. I am able to login to the LCES2 server
3. I am able to Browse and select sample projects
4. I am ble to create an Application, a folder, and a Form
5. I am able to invoke the LC Designer ES2 from within Workbench (while creating a form)
6. I am able to "invoke" an existinmg sample process in a web browser (not within workbench environment)
The main problem is...
I am NOT able to create a new process or open existing process using workbench.
Since it gives Java Platform SE error, I checked the versions of various Java Run Time Environments on my pc.
Properties of javaw.exe in different folders:
1. My Computer's JRE (common to all apps)
Folder: Program Files\Java\jre6\bin\
File Name: javaw.exe: Java Platform SE Binary
Version: 6.0.170.4
2. Adobe LiveCycleWorkbench ES2
Folder: Program Files (x86)\Adobe\Adobe LiveCycleWorkbench ES2\jre\bin\
File Name: javaw.exe: Java Platform SE Binary
Version: 6.0.20.6
2.1 Adobe LiveCycleDesigner ES2
Folder: Program Files (x86)\Adobe\Adobe LiveCycleWorkbench ES2\LiveCycleDesigner ES2\jre\bin\
File Name: javaw.exe: Java Platform SE Binary
Version: 6.0.140.6
2.2 workbench
Folder: Program Files (x86)\Adobe\Adobe LiveCycleWorkbench ES2\workbench\jre\bin\
File Name: javaw.exe: Java Platform SE Binary
Version: 6.0.70.6
I tried to use the same versions of JRE in all these folders; that didn't work..
I hope someone can throw more light on this and find the real cause.
Thanks a lot in advance!

J2ME and java.nio

I'm not sure which forum this should go in so applogies if I got it wrong.
I would like to use the java.nio package from JDK1.4 with the J2ME. Is this possible in any way?
cheers
Andrew

I'm not sure which forum this should go in so
applogies if I got it wrong.
I would like to use the java.nio package from JDK1.4
with the J2ME. Is this possible in any way?this topic should be post at
CLDC and MIDP
http://forum.java.sun.com/forum.jsp?forum=76
or
K Virtual Machine (KVM)
http://forum.java.sun.com/forum.jsp?forum=50
CLDC 1.0 and MIDP 1.0 doesn't include java.nio
please go to
http://java.sun.com/j2me/docs/
two documents will be useful
CLDC Specification, V1.0
MIDP 1.0 Specification, Final (JSR 37)

Is the Java Card Platform supports the unnamed package?

1.agree
Virtual Machine Specification for the Java Card� Platform, Version 2.2.1 chapter 2.2.2.1:
"packages in the Java Card platform are used exactly the way they are in the Java platform."
That means the Java Card platform also have two type package,named package and unnamed package.
2.against
Development Kit User�s Guide for the Java Card Platform, Version 2.2.1 chapter Running the Converter:
"Command line usage of the Converter is:
converter [ options] <package_name> < package_aid> < major_version>.
< minor_version>"
The above formula tells us that the <package_name> is a MUST Line Arguments of converter.But if we create a unnamed package,how should we express it?
3.against
first,How a real JCVM intall/organize the unnamed packages?
second,In a real JCVM run-time environment,all java items(include attribute,method and soon) refered by the suit of package+class+item.In this condition,the item in a nunamed package cannot offers the package and is never refered.
I have been botherd by the above 3 boresome and opposite points for some time and cannot give out the key of the question.
Can some one give me some ideas?
thx!

Sun's kit is free. There is a reference implementation of the JC Runtime environment with the kit.
You of course can't load that onto a card. And even if you had the RE, you won't be able to load onto a card because the RE is burned into the ROM which you don't have low level access to.
Read the JCRE specs that come with the kit

String.getBytes() & String(byte[]) - java.nio.BufferOverflowException

The application in question uses JNI for legacy integration and I suspect the legacy code is corrupting the stack causing the above error. However, the error does not occur in Java 1.3, only Java 1.4.
Is there some way to suppress 1.4's use of the native IO API when encoding and decoding byte streams? This would at least provide a workaround in the meantime.
Thanks.

This is beginning to make a little sense. The problem is that you got a String and you don't want one. A String wraps an array of chars, which your app needs, right? Specifically they're chars because you need 16-bit char sets.
Presumably the getBytes() method call is used to get an array of bytes for some data transfer operation. java.nio was probably added in 1.4 as it has some very efficient ways of handling buffers as simultaneously of two or more types. It's trying to use the underlying char array as a byte array and there's a straight up bug someplace.
Workaround is strange to contemplate, but I'm pretty sure it will work: use String.getChars() to get an array of chars, and then use java.nio yourself to create your byte array! If you've never been there, it's not very hard. I use nio all the time and it's never been a problem.

Java.nio.BufferOverflowException on big Strings ( 87MB)

Hi!
When calling getBytes() on a big String the following exception is thrown:
java.nio.BufferOverflowException
     at java.nio.charset.CoderResult.throwException(Unknown Source)
     at java.lang.StringCoding$CharsetSD.decode(Unknown Source)
     at java.lang.StringCoding.decode(Unknown Source)
     at java.lang.StringCoding.decode(Unknown Source)
     at java.lang.String.<init>(Unknown Source)
     at java.lang.String.<init>(Unknown Source)
     at com.db.janus.Janus.main(Janus.java:99)
This happens as soon as the size of the String gets bigger than 92003848 bytes.
I can reproduce it with the following code:
String x = new String(new byte[92003848]); // --> OK
String x = new String(new byte[92003849]); // --> Exception
JDK Version: 1.4.2_06
OS: Windows XP
Is this a known bug / limitation? I found a similar bug related to Java on Linux / Solaris, but this one was about getBytes() with Strings > 16MB.
Thanks for your help!

Is there any alternative to solve this problem.I am getting the error
java.nio.BufferOverflowException .This happens in my mail server when the file six\ze of xml where i have stored data about spam/nonspam grows upto 22mb.I have stored this xml in database as blob.at server startup uploading in in my class.Keeps througout in JVM after every 50 th request saving information back to database(about spam/nonspam).Now if xml size grows i am storing this in string to parse etc.it gives this bug error.Sholud i cahnge my datatype or use something as XML Parser to split my xml in pieces(mechanism i am not aware of at all) so that string just takes some size of xml (but here can i use string builder etc.). Now is there any proper solution to this kind of problem whenever i removes some daya from xml spam mail goes to inbox and vice versa.
Please suggest me some solution if possible.
complete error is:
Servlet initialization failed:
java.nio.BufferOverflowException
at java.nio.charset.CoderResult.throwException(CoderResult.java:259)
at java.lang.StringCoding$CharsetSD.decode([BII)[C(Unknown Source)
         at java.lang.StringCoding.decode(Ljava.lang.String;[BII)[C(Unknown Source)
         at java.lang.String.<init>([BIILjava.lang.String;)V(Unknown Source)
         at java.lang.String.<init>([BLjava.lang.String;)V(Unknown Source)
         at zerocode.core.ByteBlock.toString(ByteBlock.java:89)
         at zcCollab.mailProcessing.NaiveBayesClassifier._getInstanceData(NaiveBayesClassifier.java:275)
         at zcCollab.mailProcessing.NaiveBayesClassifier.initialize(NaiveBayesClassifier.java:86)
         at zcCollab.mailProcessing.SimpleDeliveryManager._setupClassifiers(SimpleDeliveryManager.java:409)
         at zcCollab.mailProcessing.SimpleDeliveryManager.<init>(SimpleDeliveryManager.java:62)
         at zcCollab.zcApp.InfoManagerApp._createDeliveryProcessor(InfoManagerApp.java:307)
         at zcCollab.zcApp.InfoManagerApp.initialize(InfoManagerApp.java:294)
         at zerocode.udm.Application._createInstance(Application.java:168)
         at zerocode.udm.Application.createInstanceForServlet(Application.java:111)
         at zerocode.servlet.UdmServlet._createApplication(UdmServlet.java:67)
         at zerocode.servlet.UdmServlet._initialize(UdmServlet.java:52)
         at zerocode.servlet.GenericServlet.init(GenericServlet.java:116)
         at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:292)
         at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:329)
         at org.mortbay.jetty.servlet.ServletHandler.dispatch(ServletHandler.java:657)
         at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:567)
         at org.mortbay.http.HttpContext.handle(HttpContext.java:1808)
         at org.mortbay.http.HttpContext.handle(HttpContext.java:1758)
         at org.mortbay.http.HttpServer.service(HttpServer.java:879)
         at org.mortbay.http.handler.ForwardHandler.handle(ForwardHandler.java:130)
         at org.mortbay.http.HttpContext.handle(HttpContext.java:1808)
         at org.mortbay.http.HttpContext.handle(HttpContext.java:1758)
         at org.mortbay.http.HttpServer.service(HttpServer.java:879)
Thanks
Vijendra

Hanging of Java API (java.io.File/java.nio)

Hi
I am facing the following problem on one of my machine , we have NFS partition mounted on the server and our application is writing on it using JAVA java.io.File/java.nio api. But when NFS is unavailable its hangs and also causes the hanging of our server. Please help me if some one already faced this problem.
NFS file system un-reachable the Java API (java.io.File/java.nio) will stuck and see if there is any solution
Thanks in advance.
Kaiser

There do not believe there is any published API for reading rules files (including the Java API, C API and VB APIs).Tim TowApplied OLAP, Inc

Java NIO - copy-on-write buffer

This is regarding peculiar behavior of a Java program on Linux-IA64 platform.
I have a Java program that uses MappedByteBuffer. For the same file, there are three buffers - read only, read/write and copy-on-write (cow)
First, change contents of cow buffer and print all buffers. The change is reflected only in cow buffer (not in ro or rw) - as expected.
Then, change contents of r/w buffer and print all buffers. The change is NOT observed in cow buffer, but reflected in ro and rw buffers (for Linux-IA64). I tried the same program in Linux-X86 and the change is reflected in all buffers (including cow buffer).
I used JDK 1.4.2_03 for compiling and running. The doc for MappedByteBuffer says
"The content of a mapped byte buffer can change at any time, for example if the content of the corresponding region of the mapped file is changed by this program or another. Whether or not such changes occur, and when they occur, is operating-system dependent and therefore unspecified."
Is this behaviour acceptable? Is this observed in any other platform?
I think Java NIO leaves it to the O/S and JVM is not doing anything here (as different from java.io). This could probably result in inconsistent behaviour across platforms (though it improves performance)
Please let me know your thoughts.

My thought is that you have posted this to the wrong forum.

Java(TM) Platform SE binary doesn't work on any website, on any browser

I'm on Windows 7 Ultimate 32bit, everything's working fine, I always keep my system clean, I also keep the registry as clean as possible, I have a problem from at least a couple of months, so "Java(TM) Platform SE binary" doesn't work on any website, on any browser, it always crash, I tried everything, I mean EVERYTHING! I've uninstalled and re-installed java a thousand of times, completely uninstalled, removed all files, all registry entries, nothing seems to work..I always get the same message..
here's the error signature:
Firma problema:
Nome evento problema: BEX
Nome applicazione: java.exe
Versione applicazione: 7.0.400.43
Timestamp applicazione: 521c3bf2
Nome modulo con errori: ntdll.dll
Versione modulo con errori: 6.1.7600.16385
Timestamp modulo con errori: 4a5bdadb
Offset eccezione: 0001d78d
Codice eccezione: c0000409
Dati eccezione: 00000000
Versione SO: 6.1.7600.2.0.0.256.1
ID impostazioni locali: 1040
Informazioni aggiuntive 1: a091
Ulteriori informazioni 2: a0912fac5db1285ab245a51982c0da6c
Ulteriori informazioni 3: 0ef4
Ulteriori informazioni 4: 0ef461fa84dd27e3340858dc9ed3bcb3
and here's a video (made by me) of the problem: Java(TM) Platform SE binary stopped working - YouTube
can anyone help me find a solution?
Thanks

Looks like you have conflict with your java home and you are running 2 different JREs. Keep the latest and try launching EM console again and post the exception if you get any.
Thanks,
Vijay

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