Calling parent method from within child object

Hello,
A quick question! Is it possible to call a method in a parent object from within a child object.By child object I mean an object that was instantiated within the parent object.
Thanks.

A quick question! Is it possible to call a method in a
parent object from within a child object.By child
object I mean an object that was instantiated within
the parent object.Since you are using ambiguous terminology, it would be much better if you provided a small sample of your code to avoid confusion. I am guessing that you are actually talking about an inner class when you say child class.
If that is correct, then you can do something like this:
class Parent {
void foo() {}
void bar() {}
class Child {
    void foo() {}
    void test() {
      bar(); // No conflicts, just call the Parent method
      Parent.this.foo(); // Use explicit qualification to avoid conflicts.

Similar Messages

Calling a method from a UICommand Object

How do I call an action method from a UICommand object?
I create a HtmlCommandLink in my backing bean, and I think I should be setting the action, but with what? The method takes a MethodBinding but I can't find much detail on how to get that. I just want to call a method like linkAction1_action() in the example below, but you cannot pass a method.
public class Page1 extends AbstractPageBean {
private HtmlPanelGroup panel = new HtmlPanelGroup();
public HtmlPanelGroup getPanel() {
    return panel;
public void setPanel(HtmlPanelGroup panel) {
    this.panel = panel;
public Page1() {
    HtmlCommandLink link = new HtmlCommandLink();
    link.setAction(/* what do I put here */);
    this.panel.getChildren().add(link);
public String linkAction1_action() {
    return "GoBack";
}

OK. A couple days later and I am able to answer my
own question. Anyway, I will lay it out there for
anyone interested. This worked for me...
public class Page1 extends AbstractPageBean {
private HtmlPanelGroup panel = new HtmlPanelGroup();
public HtmlPanelGroup getPanel() {
return panel;
public void setPanel(HtmlPanelGroup panel) {
this.panel = panel;
public Page1() {
HtmlCommandLink link = new HtmlCommandLink();
link.setAction(
FacesContext.getCurrentInstance()
.getApplication()
.createMethodBinding("#{Page1.linkAction1_action}",
new Class[0]));
this.panel.getChildren().add(link);
public String linkAction1_action() {
return "GoBack";
Since you're setting the action from within the Page1 object, why don't you create a method binding manually? This will be much more performant that using the application to create and EL-based binding.
Try:
link.setAction(new MethodBinding()
      public Object invoke(FacesContext facesContext, Object[] objects) throws EvaluationException, MethodNotFoundException
        return linkAction1_action();
      public Class getType(FacesContext facesContext) throws MethodNotFoundException
        return String.class;
});Note that you also avoid any naming convention - you do not require your Page1 object to be configured as a managed bean "Page1".

EJB 3.1 @Asynchronous and calling other methods from within

Hey all,
I am helping a friend set up a test framework, and I've turned him on to using JEE6 for the task. I am decently familiar with entity beans, session beans, and such. One of the new features is @Asynchronous, allowing a method to be ran on a separate thread. The test framework generally needs to spawn potentially 1000's of threads to simulate multiple users at once. Originally I was doing this using the Executor classes, but I've since learned that for some reason, spawning your own threads within a JEE container is "not allowed" or bad to do. I honestly don't quite know why this is.. from what I've read the main concern is that the container maintains threads and your own threads could mess up the container somehow. I can only guess that this might be possible if your threads use the container services in some way.. but if anyone could enlighten me on the details as to why this is bad, that would be great.
None the less, EJB 3.1 adds the async capability and I am now looking to use this. From my servlet I use @EJB to access the session bean, and call an async method. My servlet returns right away as it should. From the async method I do some work and using an entity bean store results, so I don't need to return a Future object. In fact, my ejb then makes an HttpClient call to another servlet to notify it that the result is ready.
My main question though, is if it's ok to call other methods from the async method that are not declared @Asynchronous. I presume it is ok, as the @Asynchronous just enables the container to spawn a thread to execute that method in. But I can't dig up any limitations on the code within an async method.. whether or not it has restrictions on the container services, is there anything wrong with using HttpClient to make a request from the method.. and making calls to helper methods within the bean that are not async.
Thanks.

851827 wrote:
Hey all,.. from what I've read the main concern is that the container maintains threads and your own threads could mess up the container somehow. I can only guess that this might be possible if your threads use the container services in some way.. but if anyone could enlighten me on the details as to why this is bad, that would be great.
Yes since the EE spec delegated thread management to conatiners, the container might assume that some info is available in the thread context that you may not have made available to your threads.
Also threading is a technical implementation detail and the drive with the EE spec is that you should concentrate on business requirements and let the container do the plumbing part.
If you were managing your own threads spawned from EJBs, you'd have to be managing your EJBs' lifecycle as well. This would just add to more plumbing code by the developer and typically requires writting platform specific routines which the containers already do anyway.
>
None the less, EJB 3.1 adds the async capability and I am now looking to use this. From my servlet I use @EJB to access the session bean, and call an async method. My servlet returns right away as it should. From the async method I do some work and using an entity bean store results, so I don't need to return a Future object. In fact, my ejb then makes an HttpClient call to another servlet to notify it that the result is ready.
My main question though, is if it's ok to call other methods from the async method that are not declared @Asynchronous. I presume it is ok, as the @Asynchronous just enables the container to spawn a thread to execute that method in. But I can't dig up any limitations on the code within an async method.. whether or not it has restrictions on the container services, is there anything wrong with using HttpClient to make a request from the method.. and making calls to helper methods within the bean that are not async.
Thanks.If you want to be asynchronous without caring about a return value then just use MDBs.
The async methods have no restrictions on container services and there is nothing wrong with calling other non async methods. Once the async method is reached those annotations don't matter anyway (unless if you call thhose methods from a new reference of the EJB that you look up) as they only make sense in a client context.
Why do you need to make the call to the servlet from the EJB? Makes it difficult to know who is the client here. Better use the Future objects and let the initial caller delegate to the other client components as needed.

No access to method from within the same class

Hey there.
First I have to excuse my English for I'm german and just learning...
Ok, my problem is as follows. I have a class called JDBC_Wrapper it includes the method sendQuery(String query). When I call this method from within another class (where 'wrapper' is my instance of JDBC_Wrapper) it works fine. For example:
wrapper.sendQuery("SELECT * FROM myDataBase");
But then I have written a method called getNumRows() into my JDBC_Wrapper class.
This method should send a query through sendQuery(Strin query) but when calling getNumRows() it says: "java.sql.SQLException: [FileMaker][ODBC FileMaker Pro driver][FileMaker Pro]Unbekannter Fehler." (Unbekannter Fehler -> Unknown Exception). What could that be?
I'm using jdk2 sdk 1.4.2 with BlueJ. My database is Filemaker Pro 6. The ODBC/JDBC connector works fine.
BerndZack

This is within my JDBC_Wrapper class:
public ResultSet sendQuery(String query)
        if(connected)
            try
                Statement s = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
                ResultSet rs = s.executeQuery(query);
                return rs;
            catch(Exception e)
                System.out.println(e);
        else
            //System.out.println("There is no connection to the datasource!");
        return null;
public int getNumRows()
        try
            ResultSet r;
            r = this.sendQuery("SELECT COUNT(*) FROM " + table_name); // At this line the error occurs
            r.next();
            return (int)r.getInt(1);
        catch(Exception e)
            System.out.println(e.getMessage());
            return -1;
}When I call sendQuery() from within another class it works, but calling getNumRows()
throws an exception.

How to call methods from within run()

Seems like this must be a common question, but I cannot for the life of me, find the appropriate topic. So apologies ahead of time if this is a repeat.
I have code like the following:
public class MainClass implements Runnable {
public static void main(String args[]) {
Thread t = new Thread(new MainClass());
t.start();
public void run() {
if (condition)
doSomethingIntensive();
else
doSomethingElseIntensive();
System.out.println("I want this to print ONLY AFTER the method call finishes, but I'm printed before either 'Intensive' method call completes.");
private void doSomethingIntensive() {
System.out.println("I'm never printed because run() ends before execution gets here.");
return;
private void doSomethingElseIntensive() {
System.out.println("I'm never printed because run() ends before execution gets here.");
return;
}Question: how do you call methods from within run() and still have it be sequential execution? It seems that a method call within run() creates a new thread just for the method. BUT, this isn't true, because the Thread.currentThread().getName() names are the same instead run() and the "intensive" methods. So, it's not like I can pause one until the method completes because they're the same thread! (I've tried this.)
So, moral of the story, is there no breaking down a thread's execution into methods? Does all your thread code have to be within the run() method, even if it's 1000 lines? Seems like this wouldn't be the case, but can't get it to work otherwise.
Thanks all!!!

I (think I) understand the basics.. what I'm confused
about is whether the methods are synced on the class
type or a class instance?The short answer is; the instance for non-static methods, and the class for static methods, although it would be more accurate to say against the instance of the Class for static methods.
The locking associated with the "sychronized" keyword is all based around an entity called a "monitor". Whenever a thread wants to enter a synchronized method or block, if it doesn't already "own" the monitor, it will try to take it. If the monitor is owned by another thread, then the current thread will block until the other thread releases the monitor. Once the synchronized block is complete, the monitor is released by the thread that owns it.
So your question boils down to; where does this monitor come from? Every instance of every Object has a monitor associated with it, and any synchronized method or synchonized block is going to take the monitor associated with the instance. The following:
synchronized void myMethod() {...is equivalent to:
void myMethod() {
    synchronized(this) {
...Keep in mind, though, that every Class has an instance too. You can call "this.getClass()" to get that instance, or you can get the instance for a specific class, say String, with "String.class". Whenever you declare a static method as synchronized, or put a synchronized block inside a static method, the monitor taken will be the one associated with the instance of the class in which the method was declared. In other words this:
public class Foo {
    synchronized static void myMethod() {...is equivalent to:
public class Foo{
    static void myMethod() {
      synchronized(Foo.class) {...The problem here is that the instance of the Foo class is being locked. If we declare a subclass of Foo, and then declare a synchronized static method in the subclass, it will lock on the subclass and not on Foo. This is OK, but you have to be aware of it. If you try to declare a static resource of some sort inside Foo, it's best to make it private instead of protected, because subclasses can't really lock on the parent class (well, at least, not without doing something ugly like "synchronized(Foo.class)", which isn't terribly maintainable).
Doing something like "synchronized(this.getClass())" is a really bad idea. Each subclass is going to take a different monitor, so you can have as many threads in your synchronized block as you have subclasses, and I can't think of a time I'd want that.
There's also another, equivalent aproach you can take, if this makes more sense to you:
static final Object lock = new Object();
void myMethod() {
    synchronized(lock) {
      // Stuff in here is synchronized against the lock's monitor
}This will take the monitor of the instance referenced by "lock". Since lock is a static variable, only one thread at a time will be able to get into myMethod(), even if the threads are calling into different instances.

Calling a Function in the Parent Window from the Child Window

QUESTION: How do I call a function resident in the parent
window from a child window?
BACKGROUND
I have a JavaScript function resident in the parent window
that reformats information obtained from the Date object and writes
the result to the parent window using the document.write( ) method.
I would like to call this function from the child window and have
it write to the child window instead. Is this possible? If not,
must I rewrite the entire function and nest it in the below code?
If so, what is the proper form of nesting?
CODE: The code that creates and fills the child window is
provided below. The highlighted area indicates where I would like
to enter the information from the function resident in the parent
window. I have tried every imaginable permutation of code that I
can imagine and nearly destroyed my parent document in the process.
I am very happy that I had a back-up copy!
function openCitationWindow() {
ciDow = window.open("", "", "width=450, height=175, top=300,
left=300");
ciDow.document.write("A proper way to cite a passage of text
on this page: Stegemann, R. A. 2000.
<cite>Imagine: Bridging a Historical Gap</cite>. " +
document.title + ". [<a href='" + location.href + "'
target='_blank'>online book</a>] <" + location.href
+ "> (");
MISSING CODE;
ciDow.document.write("). <input
type='button' value='Close Window' onclick='window.close()'>");
ciDow.focus();

Never mind - I was doing something very stupid and wasn't
calling the function as a method of a movie clip. I was simply
calling checkTarget(event) rather than
event.currentTarget.checkTarget(event); which seems to work.

How to call a set method from within a constructor

Hello,
I want to be able to call a set method from within a Scanner, to be used as the argument to pass to the Scanner (from a source file). Here's what i tried:
private void openFiles()
        input = new Scanner( setSource );
    and here is the set method:
public String setSource( String in )
        source = in;
        return source;
    }obviously there will be more code in this method but i'm trying to tackle one problem at a time. Thanks in advance..

The "String in" declaration says: "Nobody may ever invoke setSource() without specifying a certain String. The content of the String is known at run-time only."
In no place in your code you say the compiler: "I want the 'in' variable (actually, parameter) of method setSource() to contain the first arg which is passed to the application".
This is exactly the same mechanism allowing you to write "new Scanner" with something inside the two parentheses.

Is it possible to call a function in a parent component from a child component in Flex 3?

This is probably a very basic question but have been wondering this for a while.
I need to call a function located in a parent component and make the call from its child component in Flex 3. Is there a way to access functions in a parent component from the child component? I know I can dispatch an event in the child and add a listener in the parent to call the function, but just wanted to know if could also directly call a parent function from a child (similar to how you can call a function in the main mxml file using Application.application). Thanks

There are no performance issues, but it is ok if you are using the child component in only one class. Suppose if you want to use the same component as a child to some bunch of parents then i would do like the following
public interface IParentImplementation{
     function callParentMethod();
and the parent class should implement this 'IParentImplementation'
usually like the following line
public class parentClass extends Canvas implements IParentImplementation{
          public function callParentMethod():void{
     //code
in the child you should do something like this.
(this.parent as IParentImplementation).callParentMethod();
Here using the Interfaces, we re decoupling the parent and the child
If this post answers your question or helps, please mark it as such.

How do you call a method from another class without extending as a parent?

How do you call a method from another class without extending it as a parent? Is this possible?

Why don't you just create an instance of the class?
Car c = new Car();
c.drive("fast");The drive method is in the car class, but as long as the method is public, you can use it anywhere.
Is that what you were asking or am I totally misunderstanding your question?
Jen

Calling methods from the Business Object BUS2032

Hi all,
Is it possible to call methods from the Business Object BUS2032.
If so, how can it be done??
Regards,

Hi Marv,
you sure can. Here is an extract from the SAP Help. I found it at http://help.sap.com/saphelp_46c/helpdata/en/c5/e4ad71453d11d189430000e829fbbd/frameset.htm
Programmed Method Call
Call (fictitious) method Print of object type VBAK (sales document). The method receives the parameters Paperformat and Printertype as input.
* Call method Print of object type VBAK
* Data declarations
DATA: VBAK_REF TYPE SWC_OBJECT.
SWC_CONTAINER CONTAINER.
* Create object reference to sales document
SWC_CREATE_OBJECT VBAK_REF 'VBAK' <KeySalesDoc>
* Fill input parameters
SWC_CREATE_CONTAINER CONTAINER.
SWC_SET_ELEMENT CONTAINER 'Paperformat' 'A4'.
SWC_SET_ELEMENT CONTAINER 'Printertype' 'Lineprinter'.
* Call Print method
SWC_CALL_METHOD VBAK_REF 'Print' CONTAINER.
* Error handling
IF SY-SUBRC NE 0.
ENDIF.
Cheers
Graham

LVOOP "call parent method" doesn't work when used in sibling VI

It seems to me that the "call parent method" doesn't work properly according to the description given in the LabVIEW help.
I have two basic OOP functions I am doing examples for. I can get one to work easily and the other one is impossible.
Background
There are 3 basic situations in which you could use the "call parent method"
You are calling the parent VI (or method) of a child VI from within the child VI
You are calling the parent VI (or method) of a child VI from within a sibling VI
You are calling the parent VI (or method) of a child VI from a different class/object.
From the LabVIEW help system for "call parent method":
Calls the nearest ancestor implementation of a class method. You can use the Call Parent Method node only on the block diagram of a member VI that belongs to a class that inherits member VIs from an ancestor class. The child member VI must be a dynamic dispatching member VI and have the same name as the ancestor member VI
From my reading of that it means situation 3 is not supported but 1 & 2 should be.
Unfortunately only Situation 1 works in LabVIEW 2012.
Here is what I want
And this is what I actually get
What this means is that I can perform a classic "Extend Method" where a child VI will use the parent's implementation to augment it's functions BUT I cannot perform a "Revert Method" where I call the parent method's implementation rather than the one that belongs to the object.
If you want a picture
Any time I try and make operation2 the VI with the "call parent method" it shows up for about 1/2 sec and then turns into operation.
So there are only 3 possibilities I can see
Bug
Neither situation 2 or 3 are intended to work (see above) and the help is misleading
I just don't know what I am doing (and I am willing to accept this if someone can explain it to me)
The downside is that if situation 2 above doesn't work it does make the "call parent node" much less usefull AND it's usage/application just doesn't make sense. You cannot just drop the "call parent node" on a diagram, it only works if you have an existing VI and you perform a replace. If you can only perform situation 1 (see above) then you should just drop the "call parent node" and it picks up the correct VI as there is only 1 option. Basically if situation 2 is not intended to work then the way you apply "call parent method" doesn't make sense.
Attachements:
For the really keen I have included 2 zip files
One is the "Revert Method labVIEW project" which is of course not working properly because it wants to "call parent method" on operation not operation2
The other zip file is all pictures with a PIN for both "Revert Method" and "Extend Method" so you can see the subtle but important differences and pictrures of the relavant block diagrams including what NI suggested to me as the original fix for this problem but wasn't (they were suggesting I implement Extend Method).
If you are wondering where I got the names, concepts and PIN diagrams from see:
Elemental Design Patterns
By: Jason McColm Smith
Publisher: Addison-Wesley Professional
Pub. Date: March 28, 2012
Print ISBN-10: 0-321-71192-0
Print ISBN-13: 978-0-321-71192-2
Web ISBN-10: 0-321-71255-2
Web ISBN-13: 978-0-321-71255-4
All the best
David
Attachments:
Call parent node fault.zip ‏356 KB
Call parent node fault.zip ‏356 KB

Hi tst,
Thankyou for your reply. Can you have a look at my comments below on the points you make.
1) Have to disagree on that one. The help is unfortunately not clear. The part you quote in your reply only indicates that the VI you are applying "Call Parent Node" to must be dynamic dispatch. There is nowhere in the help it actually states that the call parent node applies to the VI of the block diagram it is placed into. Basically case 2 in my example fulfills all that the help file requires of it. The dynamic dispatch VI's operation are part of a class that inherits from a given ancestor. Operation 2 for Reverted behaviour is a child VI that is dynamic dispatch and has the same name as the ancestor VI (operation2). The help is missing one important piece of information and should be corrected.
2) True it does work this way. I was trying to build case 2 and had not yet built my ancestor DD for operation so the function dropped but wasn't associated with any VI. I was able to do this via a replace (obviously once the ancestor Vi was built) so this one is just bad operator
3) Keep in mind this is an example not my end goal. I have a child implementation because this is a case where I am trying to do a "reverse override" if you like.
3a) The point of the example is to override an objects method (operation2) with it's parent's method NOT it's own. The reason there is a child implementation with specific code is to prove that the parent method is called not the one that relates to the object (child's VI). If I start having to put case structures into the child VI I make the child VI have to determine which code to execute. The point of Revert method is to take this function out of the method that is doing the work. (Single Use Principal and encapsulation)
3b) The VI I am calling is a Dynamic Dispatch VI. That means if I drop the superclass's VI onto the child's block diagram it will become the child's implementation. Basically I can't use Dynamic Dispatch in this case at all. It would have to be static. That then means I have to put in additional logic unless there is some way to force a VI to use a particular version of a DD VI (which I can't seem to find).
Additional Background
One of the uses for "Revert Method" is in versioning.
I have a parent Version1 implementation of something and a child Version2. The child uses Version2 BUT if it fails the error trapping performs a call to Version1.
LabVIEW has the possibility of handling the scenario but only if both Case 1 and Case 2 work. It would actually be more useful if all 3 cases worked.
The advantage of the call parent method moving one up the tree means I don't have the track what my current object is and choose from a possible list, if, for example the hierarchy is maybe 5 levels deep. (so V4 calls V3 with a simple application of "call parent method" rather than doing additional plumbing with case structures that require care and feeding). Basically the sort of thing OOP is meant to help reduce. Anything that doesn't allow case 2 or 3 means you have to work around the limitation from a software design perspective.
If at the end of the day Case 2 and case 3 don't and won't ever work then the help file entry needs to be fixed.
All the best
David

Calling a method in an owning object

I have an application that involves an object (B) that is a member (not a sub-class) of another object (A). Within the owned object (B) I want to call up a method from the owning object A. E.g I would like to do something like this:
class A
object B; // B is a member of A
methodX( )
class B
owner.methodX( ); // invoke the methodX that is a member of object A.
Is this possible and how can i do it?

No, there is no implicit reference to an "owning" object. Think about the following code:
class Parent {
Child child
Parent(Child child) { this.child = child; }
void doSomething() {}
class Child {
class Test {
public static void main(String[] args) {
   Child child = new Child();
   Parent p1 = new Parent(child);
   Parent p2 = new Parent(child);
}So the two instances of Parent both have a reference to the same instance of Child. Which one is the "owner"?
You'll have to explicitly give your "child" object a reference to the "owner" object in order to call methods on it

Calling a method from a super class

Hello, I'm trying to write a program that will call a method from a super class. This program is the test program, so should i include extends in the class declaration? Also, what code is needed for the call? Just to make things clear the program includes three different types of object classes and one abstract superclass and the test program which is what im having problems with. I try to use the test program to calculate somthing for each of them using the abstract method in the superclass, but its overridden for each of the three object classes. Now to call this function what syntax should I include? the function returns a double. Thanks.

Well, this sort of depends on how the methods are overridden.
public class SuperFoo {
public void foo() {
     //do something;
public void bar(){
     //do something
public class SubFoo extends SuperFoo {
   public void foo() {
      //do something different that overrides foo()
   public void baz() {
      bar(); //calls superclass method
      foo(); //calls method in this (sub) class
      super.foo(); //calls method in superclass
}However, if you have a superclass with an abstract method, then all the subclasses implement that same method with a relevant implementation. Since the parent method is abstract, you can't make a call to it (it contains no implementation, right?).

Calling Java Methods from Stored Procedures

Can I call Java Methods from Oracle Stored Procedures? I have a Java framework that logs events and would like to reuse it for logging events that occur in stored procedures.
null

You need to publish java class methods to plsql.
Attached below is some information.
Although both PL/SQL modules and Java classes are stored in the database
and are managed by many of the same mechanisms, each of them resides in
its own namespace. Therefore, Java methods are not accessible from SQL
and PL/SQL by default. In order to expose Java methods to the SQL and
PL/SQL engines, first publish that Java method to the SQL namespace using
a 'Call Spec'.
Note: A 'Call Spec' does not create an additional layer of
execution so there is no performance penalty incurred.
A 'Call Spec' is simply a syntactical mechanism used to
make a method known in the SQL namespace.
The SQL name established by the 'Call Spec' can be top-level or packaged.
The syntax differs only slightly and is consistent with that used for
PL/SQL procedures and packages. For more information on the exact
syntax, see the references listed in 'Related Topics'.
In general, a top-level procedure 'Call Spec' takes the form:
CREATE OR REPLACE PROCEDURE procname ( pname mode ptype, ... )
AS LANGUAGE JAVA NAME 'javaname ( javatype, ... )';
Where: procname is the SQL name you wish to publish
pname is the name for a parameter to procname
mode is the parameter mode (i.e. IN, OUT, IN OUT)
ptype is a valid SQL type (e.g. NUMBER, CHAR, etc.)
javaname is the fully qualified name of the Java method
javatype is a Java type for the corresponding parameter
Likewise, a top-level function 'Call Spec' takes the form:
CREATE OR REPLACE FUNCTION fname ( pname mode ptype, ... ) RETURN rtype
AS LANGUAGE JAVA NAME 'javaname ( javatype, ... ) return javatype';
Where: fname is the SQL name you wish to publish
rtype is the SQL return type of the function
Note: Within the NAME clause, everything within quotes is case
sensitive. For example, if the keyword 'return' is in all
CAPS, this Call Spec will not compile.
Other optional parts of this syntax have been omitted here for simplicity.
Additional examples in subsequent sections illustrate some of these options.
eg
CREATE PROCEDURE MyProc (rowcnt IN NUMBER, numrows OUT NUMBER)
AS LANGUAGE JAVA NAME 'MyClass.MyMethod(int, int[])';
There are several important things to note here:
1.) The 'Call Spec' for a JSP must be created in the same schema as the
corresponding Java class that implements that method.
2.) IN parameters are passed by value. This is the only parameter mode
available in Java. OUT parameters, therefore, must be passed as single
element arrays in order to emulate pass by reference.
3.) Parameter names do not need to match, but the number and types of
the parameters must match (with just one exception - see item 5 below).
Oracle 8i supports conversions between an assortment of SQL and Java.
See the references listed in 'Related Topics' for additional information.
4.) Primitive types (e.g. int, float, etc.) are not required to be fully
qualified with any package name. However, standard Java object types
(e.g. String, Integer, etc.) as well as any user defined object types
(e.g. like those generated by JPublisher) must be prefixed with a
corresponding package name (e.g. java.lang) if applicable.
5.) The 'main' method which takes a single String[] parameter can be
mapped to any PL/SQL procedure or function which takes some number
of VARCHAR2 or CHAR type IN parameters. For example, the java method:
public static void main ( String[] args ) { ... }
can be mapped to each of the following:
PROCEDURE MyProc2 ( arg1 IN CHAR ) ...
PROCEDURE MyProc3 ( arg1 IN CHAR, arg2 IN VARCHAR2 ) ...
PROCEDURE MyProc4 ( arg1 IN VARCHAR2, arg2 IN VARCHAR2 ) ...
and so forth. Parameters map to the corresponding element of the String
array (e.g. arg1 -> args[0], arg2 -> args[1], etc.).
null

Calling a method from another class... that requires variables?

I'm calling a method from another class to change the date (its a date object) in another class.
I keep getting the error 'setDate(int,int,int) in Date cannot be applied to ()'
My code is:
public int changeDate()
cycleDate.setDate();
}I'm guessing I need to pass 3 parameters (day, month, year), but I'm not sure how! I have tried, but then I get errors such as ')' expected?
Any ideas! :D

f1d wrote:
I'm calling a method from another class to change the date (its a date object) in another class.
I keep getting the error 'setDate(int,int,int) in Date cannot be applied to ()'
My code is:
public int changeDate()
cycleDate.setDate();
}I'm guessing I need to pass 3 parameters (day, month, year), seems that way from the error you posted
but I'm not sure how!
setDate(16, 6, 2008);
I have tried, but then I get errors such as ')' expected?
Any ideas! :Dyou need to post your code if you're getting specific errors like that.
but typically ')' expected means just that, you have too many or not enough parenthesis (or in the wrong place, etc.)
i.e. syntax error

Calling parent method from within child object

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