Can any body please tell me what code is used for clear screen in java? For example in c++ "system("CLS"); " is used just like this what code is used in java for clear screen? Please help. Thanks!
I'm trying to convert an old Delphi program I wrote into Java to compile and run on my Android phone. I'm running the Android 2.1 operating system but am using version 1.6 of the SDK.
I have a routine in Delphi where I set the colour of pixels on a canvas individually along the lines of:
image1.canvas.pixels[x, y] := GetMyTColor(x, y);
Is there a Java equivalent to the property on the Canvas:
property Pixels[X, Y: Integer]: TColor
Currently, I have an Java Standalone Swing Application.
Now, when user clicks on the button in the Swing Application, I would like to launch another Java Application (Say : calculator.jar)
May I know what is the portable way to do so? So that it will work in multiple OS?
hey guys
I had made one application in java-swing,
Now what i am getting problem is,
i want to minimize my jframe when it is deactivate and then to maximize i want to activate that window.
So for maximize, i want to activate any jframe using java code.
So how to activate and deactivate any jframe, so that i can do something on window listeners?
thanks in advance.
Switching from JVM 1.4 to 1.5 has performance benefits as per release notes.
http://java.sun.com/j2se/1.5.0/docs/relnotes/features.html#performance
We have Java 1.4 compiled classes which are run on 1.5 JVM, will these classes suffer in performance because they were compiled using 1.4 ?
test.java:
import javax.media;
Which directories are javax.media searched from?
I suppose those in CLASSPATH specified by javac -cp will of course be searched.
But will it also search in the directory where test.java locates?
And are there any other possible places that will be searched?
SEVERE: IOException while loading persisted sessions: java.io.WriteAbortedException: writi
ng aborted; java.io.NotSerializableException:
That means this object cannot be persisted on hard disk.
Does it imply that it's not safe to keep in Session objects that do not implement "Serializable"?
I haven't heard that there are limitations on saving non-serializable objects in Session object.
It simply means that Tomcat will always keep them in memory, right?
SEVERE: IOException while loading persisted sessions: java.io.WriteAbortedException: writi
ng aborted; java.io.NotSerializableException:
That means this object cannot be persisted on hard disk.
Does it imply that it's not safe to keep in Session objects that do not implement "Serializable"?
I haven't heard that there are limitations on saving non-serializable objects in Session object.
It simply means that Tomcat will always keep them in memory, right?
I understand that the jvm is itself an application that turns the bytecode of the java executable into native machine code, but when using native threads I have some questions that I just cannot seem to answer.
Does every thread create their own
instance of the jvm to handle their
particular execution?
If not then does the jvm have to have some way to schedule which thread it will handle next, if so wouldn't this render the multi-threaded nature of java useless since only one thread can be ran at a time?
I want to a Java ME application that transfers any SMS received to a PC using bluetooth. The PC can then direct the Java ME application via bluetooth to send a response SMS. Is there library available for this architecture or I have to design it myself?
Is this approach correct or a better one exists? I want to use bluetooth as then I will not have dependency on the cable.
A friend of mine came to me with this strange behavior which i can't explain, any insight view would be appreciated.
Im running VS 2005 (C# 2.0), the following code show the behavior
int rr = "test".IndexOf("");
Console.WriteLine(rr.ToString());
the above code, print "0" which clearly show it should have return -1
This also happen in Java where the following Class show the behavior:
public class Test{
public static void main(String[] args){
System.out.println("Result->"+("test".indexOf("")));
}
}
Im running Java 1.6.0_17
The rich text editor must be implemented in Java, provide Swing support, and preferably be open source.
I'm looking to integrate it into an existing Java/Swing application.
Thanks.
I am building an application based on GXT (Java). Now the problem is that I have to connect the application to a LDAP server. Can you tell me how to connect a LDAP server from our java application and what API I will have to use for that?
I have a file directory which could look like either
C:\projects\lab3\test\test.java
or
C:\projects\assignment3\test\test.java
But the "lab3" or "assignment3" can appear anywhere in the directory, it is not a set directory
What i want is to check to see if the directory either contains "lab" or "assignment" and get the number that follows. In this case "3"
This is what i have so far
if(directory.toLowerCase().contains("lab")){
} else if (directory.toLowerCase().contains("assignment")){
}
but i do not know how to check for the char straight after the word?
I'm working on a small application in Java that takes a directory structure and renames the files according to a certain format, after parsing the original name.
What is the best Java class / methodology to use in order to facilitate these file operations?
Edit: the question is only regarding the file operations part, I got the "getting the formatted name" down :)
Hello,
I'm looking for a library that could perform "easy" pattern matching, a kind of pattern that can be exposed via GUI to users.
It should define a simple matching syntax like * matches any char and alike.
In other words, I want to do glob (globbing) like sun's implemented logic http://openjdk.java.net/projects/nio/javadoc/java/nio/file/PathMatcher.html but without relation to the file system.
Ideas?
So I have to send a java project to someone outside our company who has no experience with java and they need to compile it. Is there an easy way to do it on the windows command line that does not require writing out lists of the files?
Personally I think javac should be smart enough to handle
javac *
when in the folder just under the root of the package hierarchy. Is there anything in this ballpark?
Does anyone know of any node.js style webserver framework for java?
I realized that having nonblocking callback behavior while handling a web request will require deep support at the webserver level. I am interested in node.js, but when I have a web server that ends up persisting data, I would like to take advantage of the static type system that Java offers. However, I want the scalability of non-blocking io.
Hi..........
I am creating a notepad application in Java.I have created the text area also the menus .I have a menu called "EDIT" and under that I have "UPPERCASE"..If i select a particular text and click on "UPPERCASE" ,I want the string to be converted into uppercase.
Can anyone tell me how to implement this in Java.
(im new to java)
from my searches for Serialization in Java most of the examples document writing to a file or reading from one.
my question is lets say i have a serializable class AppMessage.
I would like to transmit it as byte[] over sockets to another machine where it is rebuilt from bytes received.
how could i achieve this please?
thanks for your insight in advance.
Does anyone know a Library which provides a Thread.sleep() for Java which has an error not higher than 1-2 Millisecond?
I tried a mixture of Sleep, error measurement and BusyWait but I don't get this reliable on different windows machines.
It can be a native implementation if the implementation is available for Linux and MacOS too.
EDIT
The link Nick provided ( http://blogs.sun.com/dholmes/entry/inside_the_hotspot_vm_clocks ) is a really good resource to understand the issues all kinds of timers/sleeps/clocks java has.
I had installed jdk-6u18-windows-i586 on my machine. Later on I uninstalled it and installed jdk 1.5.0_13 instead.
Now when I do javac -version I get
jdk 1.5.0_13
But when I do java -version I get
java version "1.6.0_19"
How do I fix this?
I've never seen a good list of free Java libraries.
What are some of your can't-live-without Java libraries?
Note: to keep this poll as useful as possible, please remember:
Post only one library per answer
We don't want duplicate answers, so before posting check if the library has been mentioned already
When adding a new library, provide a short summary of what it does / why you think it's useful
Just wondering if anybody has run Scala app or web-app on Java Real-Time system?
I assume because scala is bytecode compatible with regular JVM, then it should not take much effort to run it on a Real Time JVM such as Sun Java Real-Time System ?