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shankaranand jha

Joined: Apr 03, 2007
Posts: 1
Dear everyone
Some one told me that in java there is 5 way of object creation. If anyone have idea about this then pls gives me detail.

Shankaranand jha
Chandra Bhatt
Ranch Hand

Joined: Feb 28, 2007
Posts: 1710
Hi Jha,

Some one told me that in java there is 5 way of object creation.

There are two ways an instance of a class can be created

1- Using new operator
ClassName obj = new ClassName();
try {
}catch(Exception e) {

I would also like to know remaining three ways to create objects in java from that Anonymous guy

Thanks and Regards,

Burkhard Hassel
Ranch Hand

Joined: Aug 25, 2006
Posts: 1274
String s = "Howdy!"

Keith Lynn
Ranch Hand

Joined: Feb 07, 2005
Posts: 2398
This is from the Java Language Specification.

A new class instance is explicitly created when evaluation of a class instance creation expression (�15.9) causes a class to be instantiated.
A new class instance may be implicitly created in the following situations:

Loading of a class or interface that contains a String literal (�3.10.5) may create a new String object to represent that literal. (This might not occur if the same String has previously been interned (�3.10.5).)
Execution of an operation that causes boxing conversion (�5.1.7). Boxing conversion may create a new object of a wrapper class associated with one of the primitive types.
Execution of a string concatenation operator (�15.18.1) that is not part of a constant expression sometimes creates a new String object to represent the result. String concatenation operators may also create temporary wrapper objects for a value of a primitive type.

Creation of New Class Instances
Henrique Ordine
Ranch Hand

Joined: Sep 03, 2004
Posts: 127
If your class has a constructor which takes, for example, a String as a parameter, you could also try:

Constructor cons = YourClass.class.getConstructor(new Class[]{String.class});
YourClass obj = (YourClass) cons.newInstance(new Object[]{"Howdy!"});

J2EE Architect/Developer
I agree. Here's the link:
subject: object
It's not a secret anymore!