How to create an object of a class?

plz read the question carefully ..
how to create the object of a class by giving the class name as an String
suppose i have a java file name:" java1.java ".
so now how to create an object of this class "java1"by passing a string "java1"..

kajbj wrote:
rajeev-usendi wrote:
thanks but still i have problem..
i have created the object but now i m unable to do anything with that created object..
i have coded like this..
Object o= Class.forName("java1").new Instance();
after this i m unable to do anything with the object 'o'..So why did you create the instance? You can also get all methods using reflection, but that is probably not what you want to do. You should instead let the class implement an interface and cast the created object into that interface ans call the methods that you want to call.
KajI agree with Kaj. If you need to use a class that's unavailable at compile time, you should create an appropriate interface by which to refer to the class and then you create instances reflectively and access them normally via their interface (which is called reflective instantiation with interface access)

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How to create an object of inner class

hi i don't know how to create an object of an inner class..
i got something like
class Abc{
private class Abcd {
like this and i want to create an object of Abcd so that i can use some of method
there..
i think i should create the outter class object first right? but not sure
the syntax.. i tried something like
Abc.Abcd justTry = new Abc.Abcd()
something like this..but not work..
help me plz. ...

If the nested class (that's not technically an inner
class you have there) is not static, then you can't
refer to it with OuterClassName.InnerClassName any
more than you can refer to any other member--method
or variable--with ClassName.staticMember.
You need an instance.
It's been a while since I've created an instance of a
non-static nested class from outside that clsas, but
I think it's something like this: Outer outer = new Outer();
outer.Inner inner = new outer.Inner();
Actually, I think it is this:
Outer outer = new Outer();
outer.Inner inner = outer.new Inner();Can't test it now though, gotta go to Taco John's for TACO TUESDAY!!!!
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How to create multiple objects within a class

I have a item.lvclass which has an item.ctl (contains a cluster of class private data). I need to add another object (item2.ctl) within that same class so that I can reuse the code for that class.
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Well... right now... I've cornered myself going down this path: http://forums.ni.com/t5/LabVIEW-Idea-Exchange/LVOOP-Interfaces/idc-p/1314637#M8918
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Okay. I will try to describe the situation differently...
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both have similar properties, but also have different properties:
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How can create the object ? Via class.forName

Hi,
i want to create the object via class.forname?........
i have tryed like this Class obj=Class.forName("sample.Employee");
but it gives error like this......
java.lang.InstantiationException: sample.Employee
     at java.lang.Class.newInstance0(Class.java:291)
     at java.lang.Class.newInstance(Class.java:259)
     at sample.ArrayListTest.main(ArrayListTest.java:22)

The line
Class obj=Class.forName("sample.Employee");does NOT create a new object of class
sample.Employee. It only loads the class and creates
the Class object. You have to call newInstance() to
create a new instance of the class:
Object obj =
Class.forName("sample.Employee").newInstance();I guess you already did something like that, because
forName() itself doesn't throw an
InstantiationException.
For this to work, class sample.Employee must be in
the classpath and it must have a public constructor
that takes no arguments.this is my full code it dosn't work i don,t know
public class ArrayListTest {
public ArrayListTest() { }
public static void main(String[] args) {
ArrayList employees = new ArrayList();
// create some employees
/* Employee employee_1 = new Employee("John", 2000);
Employee employee_2 = new Employee("Carl", 3000);
Employee employee_3 = new Employee("Ron", 4000);*/
/*instead of this Employee employee_1 i want to create the new obeject by using*/
try{
Object obj = Class.forName("sample.Employee").newInstance();
catch(Exception e)
e.printStackTrace();
// add them to your list
//employees.add(employee_1);
//employees.add(employee_2);
//employees.add(employee_3);
// display only the names your list
for(int j = 0; j < employees.size(); j++) {
Employee temp = (Employee)employees.get(j);
System.out.println("nr. "+(j+1)+": "+temp.getName()+"\nnr. "+(j+1)+": "+temp.getSalary());
// invoke the toString()-method from Employee
for(int j = 0; j < employees.size(); j++) {
Employee temp = (Employee)employees.get(j);
System.out.println(temp.toString());
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again the same error occur................

How to create an object of a class contained in a .jar?

My application must use an API that is stored in a jar file. For example, in my Api.jar I have classes named Api, MyClass2, MyClass3, which have their methods declared public static.
I don't know from where to start realy. This is what I did:
I set the CLASSPATH to where my jar is. In my project properties, I added the jar as the first required library.
If in the java class where I am calling a Api.method1() I import my class with 'import MyClass1;', I get the error: "Error #: 361 : class required, but identifier found at line 20, column 1". Of course, if I don't import it, I get another error: "Class Api not found"
Is this problem caused by the fact that my jar's name is the same with one of the classes zipped in it?
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Do your classes have a state their package?
Don't forget your Jar files manifest must also state its package. This is my problem - I am using a third party .jar file, which contains 3 classes not included in any package (practically they are only zipped into a .jar). I don't know how to access them...

How to create an object class programmatically?

Guys,
I need your help. If possible with a simple example of how to do it.
I need to create an aplication that read an specification of a repository type from a file and then creates it inside my BEA Repository. The problem are few:
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I looked at documentation of ObjectClassOps but havent figured out how to do it.
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ObjectClass oc = new ObjectClass(repId, "myType", null, pds);
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How to create an object within the same class???

hi im just a newbie
i v been always creating an object from the main class..
but how to create an object inside the same class??
i got main and students class
the main got an array
Students[] stu = new Students[]
and i got
stu[i] = new Students(id,name);
i++;
but i wanna do these things inside the Students class..
i tried ..but i got errors.....
how to do this
.

javaexpert, :)
I really have no idea what you are trying to do since you say you've always been creating an object from the main class, yet you always want to create an object inside the same class.
I'll assume that you have an object in the main class that you are trying to access from the Students class.
If you are trying to access objects that are contained within the main class FROM the Students class, then know that there are two ways of doing so, one being static, and the other dynamic (look up definitions if unclear):
1.) make the objects in the main class both static and public and access the the objects using a convention similiar to: Main.object; It's important to note that Main is the name of your main class, and object is a static object. There are better ways of doing this by using gettter/setter methods, but I'll omit that tutorial.
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I don't mean to be condecending, but you should really brush up on your programming skills before posting to this forum. This is a fundamenetal concept that you will encounter time and time again.

How to create an object of our own class by using Class.forName()??

how to create an object of our own class by using Class.forName()??
plzz anser my qustion soon..

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class B
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public class ItWorksNow {
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How to create an object for this Question...

i want to create an object to Factorial.java, but the class is in String object... how can i do that
please help me with code how to create an object
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thank u

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Hi guys,
Am struck creating a HR object with subty = 99.
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Google for java reflection tutorial for more details.
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HOW TO CREATE AUTHORISATION OBJECT IN ABAP PLEASE HELP

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Check the following link
http://www.sap-img.com/bc042.htm
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Salmple at How to Create Dynamical Object for RTTC

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you can help me?.

Hello Martinez,
I have attached a sample for structure types. With the Where-Used-List on the Create() Method of the various RTTC classes one may find more samples. If you meant with object on OO Type then it is to mention that this is not possible yet.
Regards
Klaus
PROGRAM sample.
DATA: sdescr1 TYPE REF TO cl_abap_structdescr,
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      tdescr2 TYPE REF TO cl_abap_tabledescr,
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tdescr2 = cl_abap_tabledescr=>create( sdescr2 ).
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wa-sprsl = 'D'. wa-arbgb = 'ZZ'. wa-msgnr = '123'. wa-text = 'fourth text'. INSERT wa INTO TABLE <tab1>.
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How to create a object for IPageItemControlData?

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I guess the closest in today's functionality will be IHierarchy.
Dirk

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Hi lrosenth,
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How to create an object of a class?

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