Having Global Variable In Java Associated To A Process?
Aug 22, 2014Is there a way to have global variable in Java associated to a process ?
I'm coming from PL/SQL world, I'm looking for something like package variables.
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Why Global Var Initialized With Static Method And Not By Other Static Global Var Declared After Its Usage
Jul 27, 2013Take this:
class test
{
static int i=j;
static int j=10;
.....
this will give illegal forward reference ....
but this will compile successfully ..
class test
{
static int i=test1();
static test1()
{
return 20;
}
}
.....
plz assume we have main method in both cases ..
java would be loading all static members first and would be assigning default values .. and then will be running all the initializers from to bottom ..Why second case is a compile success and not first .. as in second also test1 method is declared after its usage ..
Process Of Calling Methods - Adjusting Variable Without Having It Passed Through Parameters
Feb 3, 2014eg: "Sourdough".toUpperCase();
I guess this is actually a 2-part question:
- How does this work? (nothing seems to be passed through the parameter, so how is it that the value or variable is manipulated in this fashion?)
- How would I create a method that does something similar? (ie. adjusting a variable without having it passed through the parameters)
Java Servlet :: Set Global Error Page For Every Exception Occurred At Server Side
Aug 16, 2013I am very much new to jsp and servlet. I want to set global error page for every exception occured at server side. I am trying with following code , but something is going wrong and I am not able to c error page.
package com.web;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
[Code] ....
How To Process / Parse XML Data In Java
Jul 28, 2014I'm just starting out with learning how to process/parse XML data in Java, following online code/tutorials. I am currently only printing out "catalog."
XML File that I'm trying to read: URL...
import java.io.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
[code]...
Process To Use Java SE API In Netbeans While Creating GUI?
Mar 3, 2014I would like to use java se api names like, undo, redo, stylededitorkit, htmleditorkit in editorpane swing. So, I don't understand how to use these apis.
View Replies View RelatedHow To Kill System Process From Java Code
Sep 7, 2014I need to kill or remove windows system process like cmd.exe from java code. Like removing it from end process in task mgr. I tried below code but its not removed. Is there a better way we can do this.
killing a system process from java code will create any issues?
public static void main(String[] args) throws Exception { String[] cmd = { "cmd.exe" };
Process p = Runtime.getRuntime().exec(cmd); p.destroy(); }
JSP :: Using Global And Common Function And Constants?
Jun 29, 2014How to use common functions and constants in one jsp page which are used in another jsp page on page load time?
View Replies View RelatedUser Event - Global Object Declaration
Mar 10, 2015I have an application that uses an object that is declared globally for the class. Within a method that is triggered by a user event, it creates a new object and assigns it to this global object declaration. My question is, when the object is overwritten multiple times by the user selecting the button that calls this method, will the older instances be garbage collected or is there still a reference to them? Is there any downfall to this logic and if so what would be a solution.
View Replies View RelatedJava Runtime Get Result Output From Prompt / Large File - Process Will Hang
Aug 13, 2014I am using java process to start a system command in windows
Runtime r = Runtime.getRuntime();
Process pr = r.exec(cmdString);
I want to get the prompt out put from cmdString = "cmd /c type fileSmallSize"->>>> It is ok the have the content of the file when file is small.
However, for a large file java process will hang and no Exception occurred, what is the problem?
The easiest testing you can try on the logging.properties file in java.
public static String executeCmdAndReturnPromptResult(String cmdString)
throws Exception {
LOGGER.entering(CLASSNAME,
"Entering executeCmdAndReturnPromptResult()", cmdString);
String cmd = cmdString;
[Code] ....
It seemed to me that the bufferSize is limited so that I can only have it less than a default one, how to increase it?
My question now is how to increase the size of buffer in order to read a larger InputStream ?
BufferedInputStream() default size is
private static int defaultCharBufferSize = 8192;
private static int defaultExpectedLineLength = 80;
How to make it larger and working? I tried to increase the defaultCharBufferSize to 500000000 but it did not work!
Heap Dump Generated With Read-write Permissions For Java Process Owner
Apr 14, 2014I have a question regarding the permissions set for generated heap dumps.
I have some Jetty servers running on Linux (Java 6 64 bit / Java 7 64 bit) with the following Java arguments:
-XX:+HeapDumpOnOutOfMemoryError
-XX:HeapDumpPath=/opt/apps/heapdump
When there is a out-of-memory exception a heap dump is automatically generated by the JVM. But it seems that the heap dump permisions are set to read-write for owner only (600).
When I create files then they have by default read-write for owner and group/all read access (644).
$ ls -l
total 795432
-rw------- 1 bamboop bamboo 811322265 Apr 14 09:18 java_pid337.hprof
-rw-r--r-- 1 bamboop bamboo 6 Apr 14 12:57 test
Here the umask set for the server running the Java processes
$ umask
0022
Process 10000 XML Files / Verify And Insert Data Into Database - Java Heap Memory Error
Oct 12, 2013I need to process 10000 xml files and verify and insert the data into database. I am loading all the files in the file object and iterating one by one. I am getting the memory issue. How to handle this?
View Replies View RelatedSwing/AWT/SWT :: Update Progress Of A Process In Progress Bar - Java GUI
Nov 29, 2014In my Java SWT application, I have few methods, that take longer time to complete. These methods has to be initiate and run as response to button click. There I want to implement progress bar to show the progress/status of long run method. Long run methods are Java Processes, in which it executes some command line functionality. (ex: run ls method in Linux).
Process p = Runtime.getRuntime.exec(command)
In progress bar status is set using setSelection method which takes int as argument. How to indicate the progress of process in progress bar, because I don't have int value to pass into setSelection method of progressbar.
Java Path Variable
Mar 2, 2014I have BlueJ installed on my computer and it does the job of compiling the java source code written in it. If I want to write and compile source code outside of BlueJ do I still need to download the Java SDK and set the PATH variable, even though I am apparently able to do it in BlueJ?
View Replies View RelatedHow To Communicate Two Process
Aug 5, 2014I didn't ask you to do my home work . tell me how to communicate two java program using named piped concept.
View Replies View RelatedValue Of Variable In Java - Android Studio
Jun 4, 2014I have an integer variable called 'selectedname' which is declared as shown below.
public class MainActivity extends Activity implements View.onclickListener, AdapterView.OnItemClickListener {
int selectedname;
So when the app starts an Alert Dialog with two buttons asks the user if they want to tell the first or the last name. The two buttons are 'first' and 'last'.
The problem I'm facing is that in the code the value of selectedname is suppose to change depending on the users choice as shown below.
public void displayWelcome() {
//*other code comes here but it works fine*
AlertDialog.Builder choice = new AlertDialog.Builder(this);
choice.setTitle("Yo!");
choice.setMessage("First name or last");
choice.setPositiveButton("First", new DialogInterface.onclickListener() {
public void onclick(DialogInterface dialog, int whichButton) {
selectedname = 1;
[Code] .....
Difference In Variable Assignment Between Constructor And Variable Section
May 21, 2014Given the case I have an object which is assigned only once. What is the difference in doing:
public class MyClass {
private MyObj obj = new MyObj("Hello world");
private MyClass(){}
//...
}
and
public class MyClass {
private MyObj obj;
private MyClass(){
obj = new MyObj("Hello world");
}
//...
}
Is there a difference in performance or usability? (Given also the case there are no static calls expected) ....
Are Terms Local Variable And Member Variable Comparable
Oct 27, 2014The term "Local variable" is related to scope. That is a local variable is one which is defined in a certain block of code, and its scope is confined inside that block of code.And a "Member variable" is simple an instance variable.
I read in a discussion forum that when local variables are declared (example code below), their name reservation takes place in memory but they are not automatically initialized to anything. On the other hand, when member variables are declared, they are automatically initialized to null by default.
Java Code: public void myFunction () {
int [] myInt; // A local, member variable (because "static" keyword is not there) declared
} mh_sh_highlight_all('java');
So it seems that they are comparing local variables and member variables. While I think a member variable can also be be local in a block of code, isn't it?
Application Build Process
Mar 15, 2014I need a summary of the steps involve in building java application.I have my source code, already compiled but I don't know the next step to make it run on a particular device. I know of emulator but I need more information.
View Replies View RelatedJAX-WS - Process ID Of Web Service Request
Aug 22, 2014I am using JAX-WS to develop web services.
I would like to know how i can find the process ID associated to a request.
Java - How To Make Static Variable Name To Be Dynamic
Apr 16, 2015Suppose I have a class child
public class child{
public static int age = 1;
}
And I am using class child static variable age in class school
public class school{
int var_age;
public school(){ //school constructor
var_age = child.age;
}
}
Value in age of child class could be any of these below depending on some logic:
public static int age = 1;
public static int age = 2;
How could i achieve this where should i apply that logic? Also it is mandatory for class school code to remain same.
JSP :: How To Access Variable Of Java File Into Page
Jul 4, 2014I want to access variable of java file into jsp Page. So I tried to do this but it does not work.
Problem : when I am trying to access "getName" method of java class into jsp file it displaying error, i already imported "Ajaxmethod.java" file in to "success.jsp" I want to access "getName" method in to jsp file without creating object of class.
Ajaxmethod.java
package a.b;
public class Ajaxmethod implements Action{
public String name;
public String getName() {
return name;
}
[Code]...
Pass Variable In Java From One Class / Jframe To Another
Apr 3, 2015Right so I have my ItemsPage Jframe Class and I'm trying to pass my TotalPrice variable to my CashPay so I can calculate the change. CashPrice runs and works but when I try run ItemsPage it does nothing I don't even get errors. I tried to remove that small section of trying to pass the variable to CashPay and it worked perfectly so I 100% know that's the problem. This section "public ItemsPage() { Pounds = ""; //super();
Scanner sc = new Scanner(System.in);
CashPay sendTotalPrice = new CashPay();
//System.out.println("Enter your amount");
TotalPrice = sc.nextDouble();
sendTotalPrice.printTotalPrice(TotalPrice);
"
Here is complete code for both classes, I'm using GUI builder.
import java.awt.BorderLayout;
import java.awt.Checkbox;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
[code].....
Can Add Variable To Windows PATH From Java Code?
Jan 17, 2015Can I add a variable to Windows PATH from java code?
View Replies View RelatedRead And Process File Using Thread?
Nov 4, 2014I created a main class called X and two Y and Z classes.
Y and Z implements Runnable classes.
class X contains a static array A that can be accessed in Y and Z.
The Run () method of the class Y reads an input file and populates the vector A.
The Run () method of the Z class uses data stored into the vector A to process some data.
The objective of using threads in this problem is: as the vector A is filled in the Run () method of class Y, the Run () method of the class Z will processing the received values in the vector A.
to do this I did the following calls in the main method of class X:
ObjectY y = new Y ();
Thready thread = new Thread (objectY);
threadY.start ();
ObjectZ new Z = Z ();
Threadz thread = new Thread (objectZ);
threadZ.start ();
is that correct? I'm getting the expected results, but dont know if the code is parallelized in fact.
How To Add Shipping Address During CheckOut Process
Apr 21, 2014I'm Fresher and i'm new in ATG nd right now working on checkout module.Here I'm trying to take shipping information of user so it is fetching in the shipping information JSP bt when i'm trying to submit that JSP den it's not going to either in SuccessURL or in ErrorURL it's remaining in current JSP.
I'm doing any customization's i'm jst using al Out Of Box Components nd my code is almost same as Out Of Box Code and it is not giving any error also.
I'm attaching my JSP's
Attached File(s)
shipping_jsp.txt (4.17K)
Number of downloads: 293
shippingAddress_jsp.txt (1.9K)
Number of downloads: 135
shippingSingle_jsp.txt (70bytes)
Number of downloads: 19
shippingSingleForm_jsp.txt (2.05K)
Number of downloads: 102