Global and Local Variable

Hi Gurus, I was unable to see where I can define local and global variables? I see that help.sap.com documentation but where do I create. All variables that I create, are global because, they are visible to all and they all can use it? Any help would be greatly appreciated.

As far as I know, Variables are re-usable objects that are not dependent upon InfoProvider. When I look at this link
http://help.sap.com/saphelp_nw04/helpdata/en/5c/8db07d555411d189660000e829fbbd/frameset.htm
it talks about Global and Local variable? Is this different than what we use in Query Designer?

Similar Messages

How to change value of instance variable and local variable at run time?

As we can change value at run time using debug mode of Eclipse. I want to do this by using a standalone prgram from where I can change the value of a variable at runtime.
Suppose I have a class, say employee like -
class employee {
public String name;
employee(String name){
this.name = name;
public int showSalary(){
int salary = 10000;
return salary;
public String showName()
return name;
i want to change the value of instance variable "name" and local variable "salary" from a stand alone program?
My standalone program will not use employee class; i mean not creating any instance or extending it. This is being used by any other calss in project.
Can someone tell me how to change these value?
Please help
Regards,
Sujeet Sharma

This is the tutorial You should interest in. According to 'name' field of the class, it's value can be change with reflection. I'm not sure if local variable ('salary') can be changed - rather not.

Is This a Global Versus Local Variable Problem?

I intend to use a variable (myselector) with a text value (e.g. roses, Big Sur, Pacific Grove, night, etc.) for the sort criteria of my photography list. Selection of a tab from a Tabbed Panel will appropriately define the variable and the selected thumbnails will display in the Content Panel.
The variable "myselector" is defined in the head section; a function for each tab of the Tabbed Panel will redefine the variable per the selected tab. Within the function, I am not using "var" to call the variable. Though the variable "myselector" should be global, the changes to its value are discarded when the function closes. This indicates that it is functioning like a local variable in the function. After a bit of reading, I've not found the cause of the global/local discrepancy or a fix for it.
Diagnosis History - I generated a simplified code. Variable "myselector" is defined as "abcd"; function "myfilter" is called by onclick of the text "button" and changes "myselector" to "efgh". At the end of the file, I used "document.write (myselector) to output the "myselector" value. The script follows.
The end value of "myselector" does not change. However, when I add "document.write (myselector)" to the function, then the changed value is displayed.
I ask someone to explain what I am doing incorrectly or, at least, guide me to a solution. I thank you for your assistance.
Scott
<script type="text/javascript">
var myselector="abcd";
function MM_callJS(jsStr) { //v2.0
return eval(jsStr)
</script>
</head>
<body>
<div id=text>
<p onclick="MM_callJS('myfilter();')">Button</p>
<script type="text/javascript">
function myfilter() {myselector="efgh"; }
</script>
<script type="text/javascript">
document.write (myselector);
</script>
</div>

Dear Ben:
I thank youfor your patience. This includes the script using Insert - Syntax Highlighting - Java.
The coding needs a lot of clean up but I want it to work, first.
Scott
<script src="SpryAssets/xpath.js" type="text/javascript"></script>
<script src="SpryAssets/SpryData.js" type="text/javascript"></script>
<script src="SpryAssets/SpryTabbedPanels.js" type="text/javascript"></script>
<script type="text/javascript">
var dsphotodata = new Spry.Data.XMLDataSet("EM_photo.xml", "/gallery");
</script>
<script type = "text/javascript">
function MM_callJS(jsStr) { //v2.0
return eval(jsStr)
</script>
<script type="text/javascript">
var dsphoto = new Spry.Data.XMLDataSet("EM_photo.xml", "/gallery/photos/photo");
dsphoto.filter(subjectfilter);
var myselector;
</script>
<link href="SpryAssets/SpryTabbedPanels.css" rel="stylesheet" type="text/css" />
</head>
<body>
This is a test of Scott's efforts to program his website.
<br />
<br />
<div id="TabbedPanels1" class="TabbedPanels">
<ul class="TabbedPanelsTabGroup">
    <li class="TabbedPanelsTab" tabindex="0" onclick="MM_callJS('{myselector=\'animal\'}; subjectfilter(); dsphoto.filter(subjectfilter); ')">Tab 1</li>
    <li class="TabbedPanelsTab" tabindex="0" onfocus="MM_callJS('myselector=\"pgbeach\" subjectfilter(); dsphoto.filter(subjectfilter); ')">Tab 2</li>
    <li class="TabbedPanelsTab" tabindex="0">Blank</li>
</ul>
<div class="TabbedPanelsContentGroup">
    <div class="TabbedPanelsContent" >Content 1
      <br />
<br />
<script> {document.write (myselector)} </script>
      <br />
      <div spry:region="dsphoto dsphotodata"> <img src="{dsphotodata::thumbnail/@base}{@thumbpath}" width = {@thumbwidth}px height = {@thumbheight}px spry:repeat="dsphoto" onclick="dsphoto.setCurrentRow('{ds_RowID}');" /></div>
    </div>
    <div class="TabbedPanelsContent">Content 2
      <script> {document.write (myselector)} </script>
      <br />
      <div spry:region="dsphoto dsphotodata"> <img src="{dsphotodata::thumbnail/@base}{@thumbpath}" width = {@thumbwidth}px height = {@thumbheight}px spry:repeat="dsphoto" onclick="dsphoto.setCurrentRow('{ds_RowID}');" /></div>
    </div>
    <div class="TabbedPanelsContent">Content 3 <script> {document.write (myselector)} </script><br />
<div spry:region="dsphoto dsphotodata"> <img src="{dsphotodata::thumbnail/@base}{@thumbpath}" width = {@thumbwidth}px height = {@thumbheight}px spry:repeat="dsphoto" onclick="dsphoto.setCurrentRow('{ds_RowID}');" /></div>
</div>
</div>
</div>
<div id="Selected_Photo" spry:detailregion = "dsphoto dsphotodata" >
<img src="Photo-Thumbnails/{@thumbpath}" width = {@thumbwidth}px height = {@thumbheight}px /><br />
<img src="Photo-Email/{@path}" width = {@width}px height = {@height}px />
</div>
<script type="text/javascript">
var subjectfilter = function(dataSet, row, rowNumber, criteria) { if (row["@subject"].search (myselector) != -1) return row; return null; };

</script>

Shall I use global or local variables for my program?

Hello,
1) I am using 2 while loops in parallele. One 50 ms timed and the other one 1000 ms. The 50 ms one gets data from a sensor. I want to display that data every 1000ms in the 1000 ms loop. I have used global variables to do that. Should I better use local variables?
2) This question deals with the VI I have attached
a) Shall I initialise the " Quitter programme " global variable in the main VI aswell ? Or is what I have done enough?
b)
I want the sequence to continue ( finishes the last sequence and goes back to the first one without any delay if possible ) until the user presses Quit. I am concerned about the " wait until " icon of the exterior main while loop ( set to be 250 ms at the moment ). This time, 250 ms, is the time it takes between the end of the last sequence and the beginning of the first sequence? Is that right? Once u start the first sequence, the while loop doesn’t do anything until the end of the last sequence ( my 3 sequences can take several minutes ) ?
Hope I am clear… lol
Don’t hesitate to ask any questions if not clear enough
thanks a lot,
David
Attachments:
Example1.zip ‏28 KB

Bonjour Marc. You will definitely have a race condition because you are writing to the global in a parallel loop. You could click the stop button in the quitter program, then before it is read in the main loop, the lower loop writes a false to it, and your click is lost. Why do you want a separate quitter program? You may have a good reason but it isn't clear here. I would not use globals or locals for this, just put your stop button on the main vi. You already have one, so why do you want another one in another vi? If you must do it this way, eliminate both lower loops. They are not necessary. The global default is set to false, so when you run the vi, it is false. The button mechanical action is set to latch when released, so after clicking it will turn true until the main vi reads it, then it will automatically turn false. So you don't need the lower loops to keep writing false to it. If you just eliminate both lower loops, it will work fine. The only purpose I could see for the quitter vi is to have one button cause several vi's to stop. Instead of doing it this way, put one stop button in your main vi, create a reference (right click - create - reference), and wire this reference into all subvi's that the main calls. The subvi's must be changed to accept the reference and use it. This would be a much better method to close all vi's with one button.
You could also get rid of the sequence structure (it hides code and makes it more difficult to read). Just put all your code side by side. The error in/out wire will ensure that the execution order will be fixed, just like in your first sequence with the open file and write file functions. Just wire the error out of the write vi to the second write vi, and then the error out of the second write vi to the close vi. No sequence structure needed, and all your code is viewable on one screen.
- tbob
Inventor of the WORM Global

Reading digital line and local variable

I am using digital lines in my program to start and stop "Flat Sequence Structures"
like time measurement ( 4 sequence, start and stop time with "Tick Count" )
Is it good behaviour if i use once "Read from Digital Line.vi" and other starts and stops etc. with Local variables?
Or can i just use "Read from Digital Line.vi" many times in my VI? (same line)

Most experienced LV programmers try to avoid both sequence structures and local (and global) variables. The state machine architecture is often preferred. Look at the examples with LV and search for "State machine" on this site.
I would probably use one read line or read port VI in a loop and pass the data to other, independent loops for processing (the timing) via queues.
Lynn

Default initialisation of member variables and local variables

I don't understand why member variables are initialized with default values by Java.
Objects are initialized with "null" and primitives with "0", except boolean, which is initialized with "false".
If these variables are used locally they are not initialized. The compiler requires them to be initialized by the programer, for example "String s = null".
Why? What is the use of that difference?
And why are arrays always initialized with default values, no matter if they are member variables or local variables? For example String[] s = new String[10]; s[0] to s[9] are initialized with "null", no matter if "s" is a local or member variable.
Can someone please explain that strange difference, why it is used? To me it has no sense.

Most of the time I have to initialize a local variable
with "String s = null" in order to use it because
otherwise the compile would complain. This is a cheap
little trick, but I think everyone uses it.
I wouldn't agree with "most of the time". The only cases where it is almost necessary to do that is when the variable should be initialized in a loop or a try-catch statement, and that doesn't happen too often.
If local variables were initiliazed automatically without a warning it would be a Bad Thing: the compiler could tell when there is a possibility that a variable hasn't been assigned to and prevent manymanymany NullPointerExceptions on run time.
And you didn't answer me why this principle is not
used with arrays if it is so useful as you think.
Possibly it is much more difficult to analyse the situation in the case of arrays; what if values are assigned to the elements in an order that depends on run time properties such as values returned from a random number generator.
The more special rules one has to remember, the more
likely one makes errors.I agree, but what is the rule to remember in this case?

Final attributes and local variables - performance ??

Hi all,
I and a colleague have done some performance testing regarding the use of final attributes and final local variables, e.g.
with final:
public class MyClass {
private final int i;
public final void myMethod() {
    final int j = 5;
    // do something with i and j
}vs. non-final:
public class MyClass {
private int i;
public final void myMethod() {
    int j = 5;
    // do something with i and j
}I couldn't find any speed differences in a small test program, but my colleague did so in his application. Who is right ??
Still, I will have do some formal testing next week and I will post the results.
I'd prefer the version using final anyway because I find it better readable, but the issue I am having is whether I'll spend 2-3 days going through the program making everything final or not.

I made some tests with final arguments to a method: I could not find any difference between final and non-final arguments. code is posted below
import java.io.*;
import java.net.*;
import java.rmi.*;
import java.util.*;
import javax.ejb.*;
import javax.naming.*;
import javax.rmi.PortableRemoteObject;
import junit.framework.*;
import junit.extensions.*;
public final class FinalVariablesTest extends TestCase /* from junit */ {
     * Constructors
    public FinalVariablesTest(String name) {
        super(name);
     * helper methods/classes
    protected void setUp() throws Exception {
        super.setUp();
    protected void tearDown() throws Exception {
        super.tearDown();
     * Test Suite
    public static void main(String[] args) {
     junit.textui.TestRunner.run(suite());
    public static Test suite() {
        return new TestSuite(FinalVariablesTest.class);
     * Test Cases
    /** tests the effect of passing an (final or non-final) int parameter
     to a method which uses the variable in a for loop.
     <p>
     Linux System:
     cat /proc/cpuinfo
     processor       : 0
     vendor_id       : GenuineIntel
     cpu family      : 6
     model           : 8
     model name      : Pentium III (Coppermine)
     stepping        : 1
     cpu MHz         : 501.146
     cache size      : 256 KB
     fdiv_bug        : no
     hlt_bug         : no
     sep_bug         : no
     f00f_bug        : no
     coma_bug        : no
     fpu             : yes
     fpu_exception   : yes
     cpuid level     : 2
     wp              : yes
     flags           : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr xmm
     bogomips        : 999.42
     </pre>
     <p>
     Results:
     <pre>
     java version "1.4.0"
     Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-b92)
     Java HotSpot(TM) Client VM (build 1.4.0-b92, mixed mode)
     final     non-final
     498     500
     491     494
     491     493
     491     494
     534     494
     492     494
     491     494
     492     493
     491     494
     495     494
     4966     4944 (Totals)
     </pre>
    public final void testIntParametersToForLoop() {
     final int RUNS = 10;
     final int INNER = 1000000;
     final int OUTER = 10;
     System.out.println("-----------------------");
     System.out.println("testIntParametersToForLoop");
     for(int i=0; i<RUNS; i++) {
         outerFinalIntParametersToForLoop(INNER, OUTER);
         outerNonFinalIntParametersToForLoop(INNER, OUTER);
    private final void outerFinalIntParametersToForLoop(final int INNER,
                                   final int OUTER) {
     // with final var in for loop
     long start0 = System.currentTimeMillis();
     for(int i=0; i<OUTER; i++) {
         innerFinalIntParametersToForLoop(INNER * i);
     long end0 = System.currentTimeMillis();
     System.out.println("      final:       " +
                  ( end0 - start0 ) + " milliseconds");
    private final void outerNonFinalIntParametersToForLoop(final int INNER,
                                      final int OUTER) {
     // with non-final var in for loop
     long start1 = System.currentTimeMillis();
     for(int i=0; i<OUTER; i++) {
         innerNonFinalIntParametersToForLoop(INNER * i);
     long end1 = System.currentTimeMillis();
     System.out.println(" non final: " +
                  ( end1 - start1 ) + "       milliseconds");
    private final void innerFinalIntParametersToForLoop(final int INNER) {
     for(int i=0; i<INNER; i++) {
         int testVar = i * INNER;
    private final void innerNonFinalIntParametersToForLoop(int loops) {
     for(int i=0; i<loops; i++) {
         int testVar = i * loops;

Debugging and Local Variable

Hi All
In MS visual studio i can select a local variable (Promise I will go and wash my mouth out now) and add it to a watch therefore i can see what the value of the variable as I go through the code line for line
how can I view local variable in xcode ?
Regards
Tony

To do something similar in Xcode, select the variable and either choose Run > Variables View > View Variables as Expression or choose Run > Variables View > View Variable in Window. Both options place the local variable in a separate window for you to view.
There's not much difference between the two options if you're viewing one variable, but there is a difference if you're viewing multiple variables. If you view the variable as an expression, Xcode places all the variables you want to view in one Expressions window. If you view the variable in a window, Xcode creates a new window when you choose Run > Variables View > View Variable in Window.

Scope of globle and locale variable of a Package

I have query about scope of variable declared in spec and body of a package. like
create or replace package pk_test as
v_var varchar2(50);
procedure pk_p_test;
end ;
create or replace package body pk_test as
v_var varchar2(50) := 'aaa';
procedure pk_p_test
is
--v_var varchar2(50) := 'bbbb' ;
begin
null;
--dbms_output.put_line(pk_p_test.v_var);
dbms_output.put_line(pk_test.v_var);
dbms_output.put_line(*v_var*);
end;
end;
declare
begin
pk_test.v_var := 'qqqqq';
--dbms_output.put_line(pk_test.v_var);
pk_test.pk_p_test() ;
end ;
package is allowing to declare variable having same name in spec and body.
But its not allowing to access. is it bug or .. can we access that variable using some methods

Ah, I think I can see what you are saying.
Yes, it can be declared in either place, or even declared in both places, but it shouldn't be declared in both.
One is a "public" state variable and the other is a "private" state variable, so when it creates the package state, they are both marked differently within the state and therefore unique, hence it compiles.
The public one can be accessed from outside the package, because it's clear to Oracle which is being referred to...
SQL> create or replace package pk_test as
2 v_var varchar2(50);
3 procedure pk_p_test;
4 end ;
5 /
Package created.
SQL> ed
Wrote file afiedt.buf
1 create or replace package body pk_test as
2    v_var varchar2(50) := 'aaa';
3    procedure pk_p_test is
4    begin
5      null;
6    end;
7* end;
SQL> /
Package body created.
SQL> exec pk_test.v_var := 'aaa';
PL/SQL procedure successfully completed.
SQL> set serverout on
SQL> exec dbms_output.put_line(pk_test.v_var);
aaa
PL/SQL procedure successfully completed.However if you try and access the variable from inside the package, the body is able to reference both the public and private variables, so it doesn't know which one to use. Hence the compilation error previously seen.
It's not a bug, because the packages are being flexible to allow for public and private variables, but what you are experiencing just indicates poor package design and lack of understanding of package state variables.

How to: Transform Activity: Read global/local variable, execute java code

Could anyone please show me how to do that???

could you please elaborate your usecase? yes you can read global variable using getVariableData( ) xpath function and pass them as an argument to the processXSLT ( ) xpath function.
You can read the global or local variables inside java exec using, please refer samples/references/javaexec sample.

What's the difference between global variables and instance variables?

hi im just a biginner,
but what is the difference between these two?
both i declare them above the constructor right.
and both can access by any method in the class but my teacher said
global variables are not permitted in java....
but i don't know what that means....and i got started to confuse these two types,,
im confusing.......
and why my teacher said declaring global variables is not permitted,,,,,,
why.....

instance variables are kindof like Global variables. I'm not surprised you are confused.
The difference is not in how they are declared, but rather in how they are used.
There are two different "styles" of programming
- procedural programming.
- object oriented programming.
Global variables are a term from Procedural programming.
In this style of programming, you have only one class, and one "main" procedure. You only create one instance of the class, and then "run" it.
There is one thread of control, which goes through various methods/procedures to accomplish your task.
In this style of programming instance variables ARE "global" variables. They are accessible to all methods. There is only one instance of the class, and thus only one instance of the variables.
Global variables are "bad" BECAUSE you can change them in any method you like. Even from places that shouldn't have to. Also if you use the same name as a global variable and a local variable, you can cause great trouble. This can lead to very subtle bugs, as the procedures interact in ways you don't expect.
The preferred method in procedural programming is to pass the values as parameters to the methods, and only refer to the parameters, and local variables. This means that you can track exactly what your method is doing, and what it affects. It makes it simpler to understand. If you use global variables in your methods, it becomes harder to understand.
So when are instance variables not global variables?
When you are actually using the class as an Object, rather than just a program to run. If you are creating multiple instances of an object, all with different values for their instance variables, then they are not global variables. For instance you declare a Person object with an attribute "firstname". Your "main" program then creates many instances of the Person object, each with their own "firstname"
I guess at the end of all this, it comes down to definitions.
Certainly you can write procedural code in java. You can treat your instance variables, for all intents and purposes like global variables.
I can only think to show a sort of example
public class Test1
   User[] users;
   public void printUsers(){
     // loop through and print all the users
     // uses a global variable
      for(int i=0; i<users.length; i++){
        users.printUser();
public void printUsers(User[] users){
// preferred method - pass it the info it needs to do the job
for(int i=0; i<users.length; i++){
users[i].printUser();
public Test1(){
User u1 = new User("Tom", 20);
User u2 = new User("Dick", 42);
User u3 = new User("Harry", 69);
users = new User[3];
users[0] = u1;
users[1] = u2;
users[2] = u3;
printUsers();
printUsers(users);
public static void main(String[] args)
new Test1();
class User{
String firstName;
int age;
public User(String name, int age){
this.firstName = name;
this.age = age;
public void printUser(){
// here they are used as instance variables and not global variables
System.out.println(firstName + " Age: " + age);
Shit thats a lot of typing, and I'm not even sure I've explained it any good.
Hope you can make some sense out of this drivel.
Cheers,
evnafets

Local variable's VariableElement not accessible through treepath

Hi,
I'm extending TreePathScanner visitor to localize and handle certain annotations associated with variables of any kind (field, parameters and local variables).
To do so I overrode the visitVariable method that, as far I understand, should be able to obtain the corresponding javax.lang.model's VariableElement for any variable (whatever its kind) based on the current three path, see code bellow.
It does work well with fields and parameter, however with local variables Trees.getElement simply returns a null. All the information is in fact in the code tree VariableTree node and I could retrieve what I needed from it but rather refrain from using com.sun. ... API if not really necessary and of course implement the processing twice.
Perhaps the javax.lang.model.... object tree is not built for elements within a method body? or is this a bug? com.sun.source.util.Trees#getElement javadoc only says that a null is returned if the element is not "available".
Thanks in advance.
import javax.lang.model.element.VariableElement;
import com.sun.source.util.TreePathScanner;
import com.sun.source.util.Trees;
import com.sun.source.tree.VariableTree;
import com.sun.source.util.TreePath;
public class MyVisitor extends TreePathScanner<Object,Trees> {
     @Override
     public Object visitVariable(VariableTree node, Trees trees) {
          TreePath path = getCurrentPath();
          VariableElement ve = (VariableElement) trees.getElement(path);
          if (ve != null) {
                        // The case for parameters and fields.
                        process(ve);
          else { // Funnily getElement return null for local variables
                        process(node);
          return super.visitVariable(node, trees);
}

I had a similar problem where trees.getElement(TreePath) was returning null. In my case it had to do with the fact that symbol resolution wasn't done yet. I was trying to invoke my TreePathScanner after calling javacTask.parse() but I had to switch to after calling javacTask.analyze() otherwise trees.getElement(TreePath) always returned null. My issues was with a TreePath for a method though.

Globle and local Inventory

Hi:
I know there are global inventory and local inventory. the global inventory is pointed by oraInst.loc. Where is local inventory? THX

Please see these MOS docs, it should answer your question.
Global and Local Inventory explained [ID 360079.1]
How to find the location of GLOBAL Inventory and LOCAL inventory on R12.x ? Need Clarifications Oracle Inventory [ID 878717.1]
How to create, update or rebuild the Central Inventory for Applications R12 [ID 742477.1]
Thanks,
Hussein

What is difference between local variable and property node ?

What is difference between local variable and property node ?
" 一天到晚游泳的鱼"
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我的个人网站：LabVIEW——北方客栈 http://www.labview365.com
欢迎加入《LabVIEW编程思想》组——http://decibel.ni.com/content/groups/thinking-in-labview

To make things clear, here are two small examples that show how nasty locals and value properties can be to the naive programmer.
- Open the diagram of the race condition.vi before running it and try to predict what will be the values of the two counters after the third run.
- Use the Compare Locals Properties and Wires.vi to find out how slow locals and value properties can be (times 1000+).
This being demonstrated, I must add that I use globals and value properties quite often, because they are often very convenient
Chilly Charly (aka CC)
E-List Master - Kudos glutton - Press the yellow button on the left...
Attachments:
Race condition.vi ‏9 KB
Compare Locals Properties and Wires.vi ‏18 KB

Performance with globle variable and local var.

hi anyone
i just have one performance question about the globle var and local. is having a globle var that is initialized with 'new' at one place better than having local var that is initialzed with 'new' in several places? for example, i have a access var that is initialzed with DB connection. should i have it as a globle var? or put it in the functions where it is needed, and initialize it with DB connection? in both cases, i need to use new operator.
thanks in advance.

First , don't use the term "global variable". It is misleading and not an official part of the Java nomenclature. I think the term used should be ( and correct me if I'm wrong ) instance variable. In C and C++ globale variables really are global - they can be accessed by any and all classes which include the header file.
OK, having got that out of my system, back to the question. The value is gotten from a database, right? Whether you make it an instance variable or not depends on you design and whether the value in the database is likely to change during the lifetime of the instance.
For example, if this class is a superclass of another, and the cild needs to know the value of the variable, it is often convenient to make it an instance variable so the subclass can access it directly.
But if the value is likely to change, then you may want to have a getter method which returns the current value in the database.
The latter will clearly have more overhead associated with it since you would need to get the value each time, but it is probably safer than having an instance variable.

Global and Local Variable

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