Time constrain in Core Java...not using Threads

Hi All,
I m designing a very small practice application in Java. I am running the program thru command prompt. Once the program starts, I want user t respond in certain amount of time, lets say 3 seconds.
I tried looking for some "TIMER" classes in java api docs.
most classes are used with Thread or MBean. I dont want to implement it this way.
Could anyone pls help me identify how can this be implemented in core java without any fency classes like Thread being used.
Looking forward for response.

shilpadahiya wrote:
Hi All,
I m designing a very small practice application in Java. I am running the program thru command prompt. Once the program starts, I want user t respond in certain amount of time, lets say 3 seconds. You need to be clearer. When the three seconds are over do you want the program to output "times up!" and proceed, or do you want the program to wait for as long as it takes the user to answer and only after they answer the program responds, "you took 7.9 seconds!"
I tried looking for some "TIMER" classes in java api docs.
most classes are used with Thread or MBean. I dont want to implement it this way.Why not?

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Time Machine Error Prevention - Do Not Use "/" Symbols on the names on HD!

This is a warning message:
If your Time Machine Backup Fails with the Message:
"The Backup Was Not Performed Because an Error Occurred while Copying Files To the Backup Disk. The problem May be temporary. Try again later to back up.etc.."
*If you Use Symbols In Your Names DONT!*
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*Back Story*
I had purchased a new 3TB Western Digital HD and needed to do a full backup. I never had issues with Time Machine before. But After trying 2 times and received the error message I new something was wrong.
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After reading his short post about the characters possibly causing the issue I changed the naming on one of the external USB drives to be backed up.
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Java Program Using Threads

Hi there, im really new and have just started programming in Java, i have to create a java program which implement threads. Thread.Wait, thread.start them etc.
Here is the problem, any guidance would be great cheers guys
The manager of a company employs 3 secretaries who are of varying ability, but who all work extremely fast. Secretary A is the most experienced secretary and is capable of typing up a letter once every second. Secretary B is less experienced and is capable of typing up a letter once every 2 seconds. Secretary C is the junior secretary and is capable of typing up a letter once every 4 seconds. When a secretary has typed up a letter he leaves it in the manager?s tray for him to remove and sign. The manager removes and signs a letter from the tray once every 2 seconds. The tray can hold a maximum of 5 letters at a time. The tray?s limited capacity sometimes causes the various workers to be delayed. For example, if the tray is full after a letter has been typed, the secretaries must wait until the manager makes a space available before they can add another letter to the tray. Similarly, the manager must wait for at least one letter to appear in the tray before he can take it out and sign it.
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Thread.sleep(m);
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Secretary A is ready to type a letter
Secretary A has typed a letter, number now typed = 6
Tray full. Secretary must wait until a letter has been removed before adding another
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etc
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Thanks again

Then you're probably better off enlisting one-on-one, in-person help from your instructor, a classmate, or a private tutor, or joining a study group. Forums like this are not well-suited to tutoring you from the ground up.
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Kappy's Personal Suggestions About Mac Maintenance
For disk repairs use Disk Utility. For situations DU cannot handle the best third-party utility is: Disk Warrior; DW only fixes problems with the disk directory, but most disk problems are caused by directory corruption. Drive Genius provides additional tools not found in Disk Warrior for defragmentation of older drives, disk repair, disk scans, formatting, partitioning, disk copy, and benchmarking.
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If you are using a pre-Leopard version of OS X, then an excellent solution is to download and install a shareware utility such as Macaroni, JAW PseudoAnacron, or Anacron that will automate the maintenance activity regardless of whether the computer is turned off or asleep. Dependence upon third-party utilities to run the periodic maintenance scripts was significantly reduced after Tiger. (These utilities have limited or no functionality with Snow Leopard, Lion, or Mountain Lion and should not be installed.)
Defragmentation
OS X automatically defragments files less than 20 MBs in size, so unless you have a disk full of very large files there's little need for defragmenting the hard drive except when trying to install Boot Camp on a fragmented drive. But you don't need to buy third-party software. All you need is a spare external hard drive and Carbon Copy Cloner.
Cheap and Easy Defragmentation
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1. Get an empty external hard drive and clone your internal drive to the
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Clone the internal drive to the external drive
1. Open Carbon Copy Cloner.
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hi
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import java.lang.*;
import java.util.*;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.net.*;
import java.lang.Thread;
import java.applet.Applet;
class Client1
public static void main(String argv[]) throws Exception
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Socket clientSocket=new Socket("192.168.1.2",6789);
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please send me the solution code for my problem...

sorry for inconvenience...
SERVER PROGRAM
*import java.io.*;*
*import java.net.*;*
*public class MyRunnable implements Runnable*
   *public void run() {*
   *go();*
*public void go(){*
*try {*
    *String serversen;*
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*Socket connectionSocket=welcomeSocket.accept();*
*//BufferedReader inFromClient=new BufferedReader(new //InputStreamReader(connectionSocket.getInputStream()));*
*System.out.println("enter the mess to be sent to client");*
*BufferedReader inFromuser=new BufferedReader(new InputStreamReader(System.in));*
*DataOutputStream outToClient=new DataOutputStream(connectionSocket.getOutputStream());*
*//clientsen=inFromClient.readLine();*
*//System.out.println("From Client: "+clientsen);*
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*} catch(IOException ex) {*
*        ex.printStackTrace();*
*class Server1{*
*public static void main(String argv[]) throws Exception*
     *Runnable threadJob=new MyRunnable();*
*Thread myThread=new Thread(threadJob);*
*myThread.start();*
*}*CLIENT PROGRAM
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import java.net.*;
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this is the code which i hav used using thread but i am gwetin error..ts is the error
Exception in thread "main" java.lang.NoSuchMethodError : Main

Related 2 CORE JAVA

HAI..... dis is neeraja...
I hav a question.... I wanna know how to link the HTML page to a frame by clicking on a button or menuItem using CORE JAVA without using servlets,jsp.... If anyone knows the answer plz... reply to dis as soon as possible...
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Grand central dispatch - infancy, not really doing its job, and I don't think apps have to be specifically written for HT, but they do have to not do things that they use to - prevent threads from going to sleep! or be parked.
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Windows 7 seems to be optimized for multi-core thanks to a lot of reworking. Intel wants and knows it isn't possible to hand code, that the hardware has to be smarter, too. But the OS has a job, and right now I don't think it does it properly. Or handle memory.
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One core should be owned by the OS so it is always available for its own work and housekeeping.
The iTunes audio bug last year showed how damaging and not to implement code and how a thread could usurp processing and add a high cpu temperature while basically doing nothing, sort of a denial of service attack on the processor - those 80*C temps people had.
All those new technology features under development and not like OpenCL, GCD and even OpenGL are tested, mature but rather 1.0 foundation for the future. A year ahead of readiness.

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hi sir
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I've made a small application, which starts a thread and just prints out continously some messages to the console.
After that I attached with gdb to the running process as described, and generated a core file.
Unfortunatelly on calling jdsadebugd with the core dump it throws the following exception:
jsadebugd /..../jdk1.5.0_07/bin/java core.18294 DebServ
Attaching to core core.18294 from executable /.../jdk1.5.0_07/bin/java and starting RMI services, please wait...
Error attaching to core file or starting server: sun.jvm.hotspot.debugger.DebuggerException: Can't attach to the core file
at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.attach0(Native Method)
at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.attach(LinuxDebuggerLocal.java:258)
at sun.jvm.hotspot.HotSpotAgent.attachDebugger(HotSpotAgent.java:624)
at sun.jvm.hotspot.HotSpotAgent.setupDebuggerLinux(HotSpotAgent.java:610)
at sun.jvm.hotspot.HotSpotAgent.setupDebugger(HotSpotAgent.java:323)
at sun.jvm.hotspot.HotSpotAgent.go(HotSpotAgent.java:298)
at sun.jvm.hotspot.HotSpotAgent.startServer(HotSpotAgent.java:234)
at sun.jvm.hotspot.DebugServer.run(DebugServer.java:94)
at sun.jvm.hotspot.DebugServer.main(DebugServer.java:29)
at sun.jvm.hotspot.jdi.SADebugServer.main(SADebugServer.java:46)
Even if I try to print the shared objects mapping with jmap it fails with the following message:
jmap /.../jdk1.5.0_07/bin/java core.18294
Attaching to core core.18294 from executable /.../jdk1.5.0_07/bin/java, please wait...
Error attaching to core file: Can't attach to the core file
Does anyone have an idea what goes wrong here?

How to invoke a jsp page from java which does not use Servlets?

Hello,
I am working in Documentum. I am trying to invoke a jsp page from another java page which does not use Servlets.
I tried doing this by just instantiating the java class related to the jsp page from my present java class.In my java class related to the jsp page, I have defined onInit() and onRender() methods.
Now, I am trying to call the jsp page from my present java class by just instantiating the java class related to the jsp page. This throws a java.lang.NullPointerException.
Any comments or suggestions on this.Any help would be appreciated.
Thanks,
Ranjith M.V

RanjithM.V wrote:
Hello,
Thanks for the reply. One important thing I forgot to mention. I am also using xml component.And?
As this is the standard way used for coding in Documentum, I do not want to use Beans.Well, JSP's should, in and of themselves, contain no functional code. It should all be only display.
Without that is it not possible?What did I say? I said,
masijade wrote:
It is possible, but I very, very, very, much doubt, that it would be worth the effort.And, if you don't know how, a forum is not truely going to be able to help you implement it (at least not in less than a few years time, at which point it would be outdated).
>
Appreciate your understanding and help.
Thanks,
Ranjith M.V

I need a timer function to ping the server every 5 secs??using threads.

I need a timer function to ping the server every 5 secs??
using threads...i have to use a thread coz i cant use Timer and Timer Task coz clients r on the JDK1.2 version.I have created a thread which keeps checking th ping msg & any server msg is pings 4 the1st time properly but then it just waits to read the response from server but it doesnt but the server shows that it has send the msgs to client???PLEASE HELP URGENT

Few things are not clear from your post, like, are you using sockets and if you are, how are u reading writing to them (ur sample code would help)...
Anyways if you are, are you doing accept on your socket in a while(true) loop or just once... If you do it only once you will get the first ping message but none afterwards if the other side closes and opens new sockets for every send... What I am suggesting is something like the following:
ss = new ServerSocket(port);
while(true)
     s = ss.accept();
     is = s.getInputStream();
     os = s.getOutputStream();
     reader = new BufferedReader(new InputStreamReader(is));
     writer = new BufferedWriter(new OutputStreamWriter(os));
     String in = reader.readLine();
        // do something with this string
        s.close();
        // put some check here to break out of this infinite loop
}// end of While

Time constrain in Core Java...not using Threads

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