Main methods
I have created two graphical programs using swing components. Now I have created a third and was hoping that the user could pick which program they wanted to run in this third program I made. The problem I am having is showing my first two programs. These first two programs have frames that are set up in the main method, but I can't call this method from an instance of my class can I? How can I start my applications through an instance of themselves or through another program.
I can't call this method from an instance of my class can I?Sure:
my.package.Foo.main(new String[] { "param1", "param2"});Edited by: dcminter on 25-Jun-2008 20:16
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I tried setting up a clean environment (server, EAR, web project), but haven't been able to re-solve the problem I had with the original project yet. If I could get a starting point to look for how to solve this type of error it would be greatly appreciated!I checked my JDK compliance (1.4) and the installed JREs (Standard VM; WebSphere v5.1 EE JRE; C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51_stub\java\jre)
I did notice that it was using the JRE System LIbrary [WebSphere v5.1 JRE] and I changed it to the WebSphere v5.1 EE JRE like I think it should have been...
and the web server startup begins with:
*** Starting the server ***
************ Start Display Current Environment ************
WebSphere Platform 5.1 [BASE 5.1.0.3 cf30412.02] [JDK 1.4.1 b0344.02] running with process name localhost\localhost\server1 and process id 2692
Host Operating System is Windows XP, version 5.1
Java version = J2RE 1.4.1 IBM Windows 32 build cn1411-20031011 (JIT enabled: jitc), Java Compiler = jitc, Java VM name = Classic VM
was.install.root = C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51
user.install.root = C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51
Java Home = C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51\java\jre
ws.ext.dirs = C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51/java/lib;C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51/classes;C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51/classes;C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51/lib;C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51/lib/ext;C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51/web/help;C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51/deploytool/itp/plugins/com.ibm.etools.ejbdeploy/runtime;C:/Program Files/IBM/SQLLIB/java/db2java.zip;C:/Program Files/IBM/WebSphere Studio/Application Developer/v5.1.2/wstools/eclipse/plugins/com.ibm.etools.webservice_5.1.2/runtime/worf.jar
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************* End Display Current Environment ************* -
Bouncing Ball without Main Method
Hi. I needed to reserch on the Internet sample code for a blue bouncing ball which I did below. However, I try coding a main class to start the GUI applet and it's not working. How can I create the appropriate class that would contain the main method to start this particular application which the author did not provide? The actual applet works great and matches the objective of my research (http://www.terrence.com/java/ball.html). The DefaultCloseOperation issues an error so that's why is shown as remarks // below. Then the code in the Ball.java class issues some warning about components being deprecated as shown below. Thank you for your comments and suggestions.
Compiling 2 source files to C:\Documents and Settings\Fausto Rivera\My Documents\NetBeansProjects\Rivera_F_IT271_0803B_01_PH3_DB\build\classes
C:\Documents and Settings\Fausto Rivera\My Documents\NetBeansProjects\Rivera_F_IT271_0803B_01_PH3_DB\src\Ball.java:32: warning: [deprecation] size() in java.awt.Component has been deprecated
size = this.size();
C:\Documents and Settings\Fausto Rivera\My Documents\NetBeansProjects\Rivera_F_IT271_0803B_01_PH3_DB\src\Ball.java:93: warning: [deprecation] mouseDown(java.awt.Event,int,int) in java.awt.Component has been deprecated
public boolean mouseDown(Event e, int x, int y) {
2 warnings
import javax.swing.*;
public class BallMain {
* @param args the command line arguments
public static void main(String[] args) {
Ball ball = new Ball();
//ball.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
ball.setSize( 500, 175 ); // set frame size
ball.setVisible( true ); // display frame
import java.awt.*;*
*import java.applet.*;
import java.util.Vector;
// Java Bouncing Ball
// Terrence Ma
// Modified from Java Examples in a Nutshell
public class Ball extends Applet implements Runnable {
int x = 150, y = 100, r=50; // Position and radius of the circle
int dx = 8, dy = 5; // Trajectory of circle
Dimension size; // The size of the applet
Image buffer; // The off-screen image for double-buffering
Graphics bufferGraphics; // A Graphics object for the buffer
Thread animator; // Thread that performs the animation
boolean please_stop; // A flag asking animation thread to stop
/** Set up an off-screen Image for double-buffering */
public void init() {
size = this.size();
buffer = this.createImage(size.width, size.height);
bufferGraphics = buffer.getGraphics();
/** Draw the circle at its current position, using double-buffering */
public void paint(Graphics g) {
// Draw into the off-screen buffer.
// Note, we could do even better clipping by setting the clip rectangle
// of bufferGraphics to be the same as that of g.
// In Java 1.1: bufferGraphics.setClip(g.getClip());
bufferGraphics.setColor(Color.white);
bufferGraphics.fillRect(0, 0, size.width, size.height); // clear the buffer
bufferGraphics.setColor(Color.blue);
bufferGraphics.fillOval(x-r, y-r, r*2, r*2); // draw the circle
// Then copy the off-screen buffer onto the screen
g.drawImage(buffer, 0, 0, this);
/** Don't clear the screen; just call paint() immediately
* It is important to override this method like this for double-buffering */
public void update(Graphics g) { paint(g); }
/** The body of the animation thread */
public void run() {
while(!please_stop) {
// Bounce the circle if we've hit an edge.
if ((x - r + dx < 0) || (x + r + dx > size.width)) dx = -dx;
if ((y - r + dy < 0) || (y + r + dy > size.height)) dy = -dy;
// Move the circle.
x += dx; y += dy;
// Ask the browser to call our paint() method to redraw the circle
// at its new position. Tell repaint what portion of the applet needs
// be redrawn: the rectangle containing the old circle and the
// the rectangle containing the new circle. These two redraw requests
// will be merged into a single call to paint()
repaint(x-r-dx, y-r-dy, 2*r, 2*r); // repaint old position of circle
repaint(x-r, y-r, 2*r, 2*r); // repaint new position of circle
// Now pause 50 milliseconds before drawing the circle again.
try { Thread.sleep(50); } catch (InterruptedException e) { ; }
animator = null;
/** Start the animation thread */
public void start() {
if (animator == null) {
please_stop = false;
animator = new Thread(this);
animator.start();
/** Stop the animation thread */
public void stop() { please_stop = true; }
/** Allow the user to start and stop the animation by clicking */
public boolean mouseDown(Event e, int x, int y) {
if (animator != null) please_stop = true; // if running request a stop
else start(); // otherwise start it.
return true;
}FRiveraJr wrote:
I believe that I stated that this not my code and it was code that I researched.and why the hll should this matter at all? If you want help here from volunteers, your code or not, don't you think that you should take the effort to format it properly? -
Object life in main method after frame created
hi
i'm having a slight problem with the life of an object i'm creating in the main method of my application.
i have a JDesktopPane that is initialised in the main class's main method and constructor. within the main method i also add the first internal frame to the desktop.
after the user completes the details of the first frame, another is called (from this first frame) and the first frame is disposed.
the problem is that although all subsequent internal frames added to the desktop outside the main class, they are garbage collected with no problems (i'm using a profiler), however the first frame and the frame created from that first frame are never collected due to the reference maintained in the main class. i've tried adding the creation of these frames outside the main class but given that these methods are called from main the reference is still maintained.
is there any way to create those first 2 frames without the reference being maintained in the main class such that they become elegible for garbage collection? do i have it all wrong perhaps and my approach is bad?? any help would be greatly appreciated.
thanks heaps.
Takishi
thanks for your reply.
i tried that and it didn't work. the instance of that first internal frame is still there.
i really am at a loss with this one.
any other suggestions would be greatly appreciated.
Takis -
Need help - how to run this particular method in the main method?
Hi all,
I have a problem with methods that involves objects such as:
public static Animal get(String choice) { ... } How do we return the "Animal" type object? I understand codes that return an int or a String but when it comes to objects, I'm totally lost.
For example this code:
import java.util.Scanner;
interface Animal {
void soundOff();
class Elephant implements Animal {
public void soundOff() {
System.out.println("Trumpet");
class Lion implements Animal {
public void soundOff() {
System.out.println("Roar");
class TestAnimal {
public static void main(String[] args) {
TestAnimal ta = new TestAnimal();
ta.get(); // error
// doing Animal a = new Animal() is horrible... :(
public static Animal get(String choice) {
Scanner myScanner = new Scanner(System.in);
choice = myScanner.nextLine();
if (choice.equalsIgnoreCase("meat eater")) {
return new Lion();
} else {
return new Elephant();
}Out of desperation, I tried "Animal a = new Animal() ", and it was disastrous because an interface cannot be instantiated. :-S And I have no idea what else to put in my main method to get the code running. Need some help please.
Thank you.Hi paulcw,
Thank you. I've modified my code but it still doesn't print "roar" or "trumpet". When it returns a Lion or an Elephant, wouldn't the soundOff() method get printed too?
refactored:
import java.util.Scanner;
interface Animal {
void soundOff();
class Elephant implements Animal {
public void soundOff() {
System.out.println("Trumpet");
class Lion implements Animal {
public void soundOff() {
System.out.println("Roar");
class TestAnimal {
public static void main(String[] args) {
Animal a = get();
public static Animal get() {
Scanner myScanner = new Scanner(System.in);
System.out.println("Meat eater or not?");
String choice = myScanner.nextLine();
if (choice.equalsIgnoreCase("meat eater")) {
return new Lion();
} else {
return new Elephant();
}The soundOff() method should override the soundOff(); method in the interface, right? So I'm thinking, it should print either "roar" or "trumpet" but it doesn't. hmm.. -
How can i call a main method from a different class???
Plzz help...
i have 2 classes.., T1 and T2.. Tt2 is a class with a main method....i want to call the main method in T2......fromT1..is it possibl..plz helpT2.main(args);
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How to add a code TestIfElse(10) to the Main method of the Program.cs class?
How to add a code TestIfElse(10) to the Main method of the Program.cs class?
Here is my code and I have copied from the Wiley book for Microsoft certification page 14,
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ifelse_Statement
class Program
static void Main(string[] args);
TestIfElse(10);
public static void TestIfElse(int n);
if(n < 10)
Console.WriteLine("n is less than 10");
else if(n < 20)
Console.WriteLine("n is less than 20");
else if(n < 30)
Console. WriteLine("n is greater than or equal to 30");
Here is the error list I am getting,
Error 1 Method must have a return type C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\switch_Statement\Program.cs
12 13
switch_Statement
Error 2
Type expected C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\switch_Statement\Program.cs
12 24
switch_Statement
Error 3
Method must have a return type C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
12 9
ifelse_Statement
Error 4
Type expected C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
12 20
ifelse_Statement
Error 5
Invalid token 'if' in class, struct, or interface member declaration
C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
16 9
ifelse_Statement
Error 6
Invalid token '10' in class, struct, or interface member declaration
C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
16 16
ifelse_Statement
Error 7
Type expected C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
16 16
ifelse_Statement
Error 8
Invalid token '(' in class, struct, or interface member declaration
C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
18 35
ifelse_Statement
Error 9
A namespace cannot directly contain members such as fields or methods
C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
20 10
ifelse_Statement
Error 10
Type or namespace definition, or end-of-file expected
C:\Users\PVS\documents\visual studio 2013\Projects\Lesson01\ifelse_Statement\Program.cs
30 1
ifelse_Statement
Error 11
The type or namespace name 'n' could not be found (are you missing a using directive or an assembly reference?)
c:\users\pvs\documents\visual studio 2013\projects\lesson01\ifelse_statement\program.cs
16 12
ifelse_Statement
Error 12
'System.Console.WriteLine(string, params object[])' is a 'method' but is used like a 'type'
c:\users\pvs\documents\visual studio 2013\projects\lesson01\ifelse_statement\program.cs
18 26
ifelse_Statementstatic void Main(string[] args){
TestIfElse(10);
public static void TestIfElse(int n)
if (n < 10)
Console.WriteLine("n is less than 10");
else if (n < 20)
Console.WriteLine("n is less than 20");
else if (n < 30)
Console.WriteLine("n is greater than or equal to 30");
Fouad Roumieh -
Class extending a Frame with main method in it - how do I use the methods?
Howdy.
Having a problem.. I want my "main" class, ie. the class with the main method in it to extend a Frame class.. because the main method is static, I can't use Frame's methods.
What's a trick to get around this ? I am making a deliberate design decision to extend the Frame class, because I thought it was.. well.. better. I could always just create a Frame object and utilise it.. but from little things I've read and seen it's better to extend it.
When I use Forte to make a Frame program it sets up a constructor/etc. for the main class and then it does something akin to this (the class is called MazeGenerator) :
public static void main(String args[]) {
new MazeGenerator().show();
What does "new MazeGenerator().show();" do when it's not being associated to an object handle ??
Ta.
- Scutt.Create an instance of the frame in main then the constructor can control it. Or you could add an init method or something:
class MyFrame extends Frame {
public static void main (String [] args) {
MyFrame frame = new MyFrame();
frame.init();
You don't necessarily have to have a reference to an Object in order to create one. All the work can be done in the constructor (something I'm not really fond of however) -
Calling main method in another class using command line arguements
Hi
My program need to use 4 strings command line arguments
entered in Project properties/Run/Application Parameters
java programming for beginners // arguments
The program needs to call main in the second class 4 times using argument 1 the first call, argument 2 the second call on so on.
So the output wil be
java
programming
for
beginners
import java.lang.*;
public class First extends Second{
public static void main(String[] args) {
for(int i = 0; i < args.length; i++){
Second.main(args); // Error I think
import java.lang.*;
public class Second {
public static void main(String[] args){
System.out.println(args[0]);
"First.java": Error #: 300 : method main(java.lang.String) not found in class Second at line 6, column 15
I am only a beginner with little knowledge of java so can the code be as basic as possibleYour style looks quite bad for starters..... Hows
this://import java.lang.*; /* NOT NEEDED */
public class First extends Second{
public First(String s) {
super(s);
public static void main(String[] args) {
for(int i = 0; i < args.length; i++){
new First(s);
public class Second {
public Second(String s)
System.out.println(s);
NOT NEEDED:
public static void main(String[] args){
System.out.println(args[0]);
}My question to you: Do you understand why my code
works? (does it do what you want?)I think since this is some kind of lesson, the OP have to implement some way to use the main method of the Second class as it is, that is, with String[] args. I think this lesson is interesting exactly because of this requirenment. But, anyway, I don�t know, that is just my assumption... -
Does not contain a static 'Main' method suitable for an entry point_
Hello
I want to to do a project with Entiity Framework . I add a project to my solution for my domain class and it's name is 'LinkModel.DomainClasses'. when I prees F5 there is an error like bellow.
Could You help me to solve this? thanks alot
..\Documents\Training\LinkCodeFirstLast\LinkCodeFirst\LinkCodeFirst\LinkModel.DomainClasses\obj\Debug\LinkModel.DomainClasses.exe'
does not contain a static 'Main' method suitable for an entry pointHi bkshn,
This error is caused by the missing "Main" method in your project. it is the entry point of your project.
If you want to create a EF project, you could follow the way in the aricle below.
https://msdn.microsoft.com/en-us/data/ee712907#codefirst
The Main method is like below.
class Program
static void Main(string[] args)
using (var db = new BloggingContext())
// Create and save a new Blog
Console.Write("Enter a name for a new Blog: ");
var name = Console.ReadLine();
var blog = new Blog { Name = name };
db.Blogs.Add(blog);
db.SaveChanges();
// Display all Blogs from the database
var query = from b in db.Blogs
orderby b.Name
select b;
Console.WriteLine("All blogs in the database:");
foreach (var item in query)
Console.WriteLine(item.Name);
Console.WriteLine("Press any key to exit...");
Console.ReadKey();
And you could start to learn the EF from the following MSDN blogs.
https://msdn.microsoft.com/en-us/data/ee712907
If you have any other concern regarding this issue, please feel free to let me know.
Best regards,
Youjun Tang
We are trying to better understand customer views on social support experience, so your participation in this interview project would be greatly appreciated if you have time. Thanks for helping make community forums a great place.
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HERE to participate the survey. -
Projectname.exe' does not contain a static 'Main' method suitable for an entry point .
Hi,
I'm developing a blog reader for windows 8 store app. It was perfectly worked before. But because of some miss behave my coding i get below error. No other errors there.
Error 1 Program 'c:\Users\.........\Desktop\Blog_Reader\Blog_Reader\obj\Release\intermediatexaml\Blog_Reader.exe' does not contain a static 'Main' method suitable for an entry point C:\Users\..........\Desktop\Blog_Reader\Blog_Reader\CSC
Blog_Reader
Please help me to figure this.
Thank You!Go to your App.Xaml and R-Click Go to Properties
Check whether the Build Action is ApplicationDefinition
If not change it to ApplicationDefinition. Clean the code (solution ) and Deploy..
Chears.... -
Hi,
I'm developed a blog reader for windows 8 store app. It was perfectly worked before. But suddenly it started to miss behave and I got an
error. No other errors were there other than that.
Error
Program c:\Users\.........\Desktop\Blog_Reader\Blog_Reader\obj\Release\intermediatexaml\Blog_Reader.exe' does not contain a static 'Main'
method suitable for an entry point.
C:\Users\..........\Desktop\Blog_Reader\Blog_Reader\CSC Blog_Reader
But I found the solution while I fixing it.
Solution for that is like below.
Go to your App.Xaml and Right-Click thenGo to Properties
Check whether the Build Action is
ApplicationDefinition
If not change it to ApplicationDefinition.
Clean the code (solution) and Deploy
Now the error is fiexed.Hi Robana,
Good sharing on the Technet.
This will definitely benefit other who may encounter the same issue as yours.
Thanks for your sharing again.
Kate Li
TechNet Community Support -
Running a java application without a main method
class MainMethodNot
static
System.out.println("This java program have run without the run method");
System.exit(0);
}The reason this works is that static initialization blocks get executed as soon as the class is loaded, even before the main method is called. During run time JVM will search for the main method after exiting from this block. If it does not find the main method, it throws an exception. To avoid the exception System.exit(0); statement is used which terminates the program at the end of the static block itself.
got it from http://www.java-tips.org/This has been published many times on this forum. What is your question?
-
Does main method have to be static? Is there a way to go around it?
I am trying to write a class that will recursively walk through directory listing of a given ftp adress and store it in a text file in this format:
<path> , DIR // if directory
<path> , file // if file
Since I am not yet experienced to do my own socket programming(tried and did not work out) I used Secure iNet Factory's library. And since I will be running multiple instances of this class I concluded that my fields and methods should not be static. Here is the class I wrote:
import com.jscape.inet.ftp.Ftp;
import com.jscape.inet.ftp.FtpException;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.net.URL;
import java.util.Enumeration;
import java.util.logging.Level;
import java.util.logging.Logger;
public class test {
private String path = "/";
private String name;
private String adres;
// create new Ftp instance and connect.
public test(String Name, String Adres) throws IOException {
name = Name;
adres = Adres;
System.out.println("Test class: " + name);
try {
Ftp ftp = new Ftp(adres,"anonymous","anonymous");
ftp.connect();
Enumeration e = ftp.getDirListing();
iterate(path, ftp);
ftp.disconnect();
catch (FtpException ex) {
Logger.getLogger(test.class.getName()).log(Level.SEVERE, null, ex);
void iterate(String aStartingDir, Ftp ftp) throws FtpException, IOException {
//Set the path.
path = path + aStartingDir + "/";
// Change directory.
ftp.setDir(aStartingDir);
// Iterate through directory list.
Enumeration e = ftp.getDirListing();
while(e.hasMoreElements()){
Object f = e.nextElement();
// Recursive call if item is directory.
if(f.toString().startsWith("drwxrwxrwx") &&
// Ignore "." and ".."
!f.toString().substring(55).trim().equalsIgnoreCase(".") &&
!f.toString().substring(55).trim().equalsIgnoreCase("..")) {
// Write to index file.
URL dirUrl = FtpCheck.class.getResource("./index/"); // get the directory.
URL fileUrl = new URL(dirUrl, name + ".txt"); // construct the file path.
String filePath = fileUrl.getPath().replaceAll("%20", " "); // fix spaces.
BufferedWriter file = new BufferedWriter(new FileWriter(filePath,true));
file.write((path + f.toString().substring(55).trim()).substring(3)
+ ",DIR\n");
file.close();
iterate(f.toString().substring(55).trim(),ftp);
// Skip entries "." and ".."
else if (f.toString().substring(55).trim().equalsIgnoreCase(".") ||
f.toString().substring(55).trim().equalsIgnoreCase("..")) {
continue;
// Add files to the index.
else {
URL dirUrl = FtpCheck.class.getResource("./index/"); // get the directory.
URL fileUrl = new URL(dirUrl, "index.txt"); // construct the file path.
String filePath = fileUrl.getPath().replaceAll("%20", " "); // fix spaces.
BufferedWriter file = new BufferedWriter(new FileWriter(filePath,true));
file.write((path + f.toString().substring(55).trim()).substring(3)
+ ",file\n");
file.close();
// End of listing reached, go one directory up.
ftp.setDirUp();
// And remove the last directory name from path.
path = path.substring(0,path.lastIndexOf("/"));
path = path.substring(0,path.lastIndexOf("/")) + "/";
}which compiles fine.
Here is the class that invokes it:
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.MalformedURLException;
import java.util.logging.Level;
import java.util.logging.Logger;
* @author Sentinel
public class NewClass {
public NewClass() {
public static void main(String args[]) throws MalformedURLException, FileNotFoundException, IOException {
index t = new index("El Naga","elnaga.sytes.net");
t.start();
index t1 = new index("Afacan","afacan.myftp.org");
t1.start();
public class index extends Thread {
String name;
String adres;
public index(String Name,String Adres) {
name = Name;
adres = Adres;
@Override
public void run() {
try {
test checker = new test(name,adres);
catch (IOException ex) {
Logger.getLogger(NewClass.class.getName()).log(Level.SEVERE, null, ex);
}when I hit run build fails:
init:
deps-jar:
Compiling 1 source file to C:\Documents and Settings\Sentinel\My Documents\NetBeansProjects\ftpCheck\build\classes
C:\Documents and Settings\Sentinel\My Documents\NetBeansProjects\ftpCheck\src\NewClass.java:19: non-static variable this cannot be referenced from a static context
index t = new index("El Naga","elnaga.sytes.net");
^
C:\Documents and Settings\Sentinel\My Documents\NetBeansProjects\ftpCheck\src\NewClass.java:20: non-static variable this cannot be referenced from a static context
index t1 = new index("Afacan","afacan.myftp.org");
^
2 errors
BUILD FAILED (total time: 0 seconds)I (now)know that main method has to be static. I'm stuck and in need of help to overcome this obstacle. Is there a way to do this?a stab in the dark, but what if you make index a non-internal class. make it a stand-alone class in it's own file. Either that or make it a static inner class (almost the same thing).
Your problem is that an inner class needs an instance of the outer class to start on, and you're not doing this. Another solution would be to do this kludge:
index t = new NewClass().new index("El Naga","elnaga.sytes.net"); // I think this is how to call itBut again better is to make index a stand-alone class.
Edited by: Encephalopathic on Oct 28, 2008 8:06 AM -
When is the inteface variable in an EJB mains method initiated?
hI,
the code bellow is part of a simple EE 6 example from Yuri Vasilievs book Beginning Database-Driven...
Can somone tell me when the variable customerSession bellow will be initiated in the CustomerSessionClient class bellow.
When I run theCustomerSessionClient (main methode) in my netbeans environment the customerSession is allways null?
Bellow first the inteface class and then the CustomerSessionClient class
package ejbjpa.client;
import javax.ejb.Remote;
* @author xxx
@Remote
public interface CustomerSession {
public String getCustomerAddress(Integer customer_no);
import ejbjpa.ejb.CustomerSession;
import javax.ejb.EJB;
* @author xxx
public class CustomerSessionClient {
@EJB
private static CustomerSession customerSession;
public static void main(String[] args){
System.out.println("Billing address of the customer whose id is: "+customerSession.getCustomerAddress(1));
Brg
Javanalle
Edited by: 873848 on Jul 20, 2011 8:56 PMCan somone tell me when the variable customerSession below will be initiated in the CustomerSessionClient class below.It will never be initialized.
When I run theCustomerSessionClient (main method) in my netbeans environment the customerSession is always null?I agree.
That's just a command-line client. It doesn't execute in an EJB container, so the @EJB annotation never takes effect. -
How to increase the Java Heap Space for a main method
Hello all,
after a given number of calculations inside a class with main-method, I get an OutOfMemoryError (Java Heap Size).
So I'm just trying to increase the Heap Size Creator uses, but it won't work.
After reading a lot of posts and online-articles, I tried the following:
1) I changed the -Xms and -Xmx options (to 512m) both in
$CREATOR/SunAppServer8/domains/creator/config/domain.xml and
$CREATOR/etc/creator.conf (this file also points to the Creator built-in JDK)
2) additionally I tried to start Creator from the console with the respective option:
./creator -J-Xmx512m
The memory toolbar shows the right value, but when I use
System.out.println("JVM maximum memory:\t"+Runtime.getRuntime().maxMemory()/1024+" KB\n");it always says 64 MB, no matter which option I chose in the config-files.
So how can I increase this value?
Regards,
Felix
Message was edited by:
Felice
Message was edited by:
FeliceThank you very much,
this was an important hint. Additionally I had to create a new "Java Class Library" project with a copy of the needed files (those that are not dependent on the Application Server). Then I could use the option you mentioned.
Unfortunately, when I try to run the file with
java -jar FILENAME.jarit won't work, because the archive is not complete: MANIFEST.MF lacks the main-class and all involved libraries.
I managed to add the main-class attribute manually, but adding all library references seems to be very error-prone.
So does anyone know if I did something wrong or if this is a bug of Creator?
Regards,
Felix
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