File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
The moose likes Programmer Certification (SCJP/OCPJP) and the fly likes String inNutShell Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Certification » Programmer Certification (SCJP/OCPJP)
Bookmark "String inNutShell" Watch "String inNutShell" New topic

String inNutShell

Amit Prakash Singh
Ranch Hand

Joined: May 11, 2006
Posts: 38
hi jerry...
here is how Strings works:

whenever you apply any method on string objects, compiler automatically generates a new copy of orgional string objects, performs operation on new one and then returns the modiifed string objects. old one is not touched. so its up to you if you want to assign the reutrned object a reference or not.


String s = "XYZ"; //1. a object created

s.concat("ABC"); //now a fresh copy of XYZ created and "ABC" to it and the
//reference to XYZABC returned, but it get lost
//as you are not assiging reference to it.
System.out.println(s); // its "XYZ"

now lets see if you write:

System.out.println(s.concat("ABC")); //it will print XYZABC but the s=XYZ

if you write:
s = s.concat("ABC"); //then s=XYZABC

Amit Prakash Singh<br /> <br />SCJP 1.4 93% <br />SCWCD1.5 85%
subject: String inNutShell
jQuery in Action, 3rd edition