Java Glossary : wrapper

Java definitions: 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

You are here : home : Java Glossary : W words : wrapper.

wrapper: Java won't let you change a caller's variable. However it will let you change the fields inside a caller's object passed to you as a parameter. To get around the limitation that you can't change the caller's variables, (or return multiple values), you create a dummy class. You can then have the caller pass you an object of that dummy class and you fiddle its fields. Alternatively you create such an object, fill in its fields and return it to the caller. That dummy class is called a wrapper. The term is also used for an immutable Integer -- a wrapper around an int to turn it into an object. Wrappers are sometimes called holders.
Wrapper has a totally different meaning. If you create a facade or decorator class, that just calls methods from other classes without doing any work itself, that class is called a wrapper.
call by reference ¤ decorator ¤ design patterns ¤ facade ¤ immutable ¤ int vs Integer ¤ mutable

home	Canadian Mind Products
	mindprod.com IP:[24.87.56.253]
	Your IP:[80.134.30.163]
	You are visitor number 1496.
	Please send errors, omissions and suggestions
	to improve this page to Roedy Green.
	You can get a fresh copy of this page from:	or possibly from your local J: drive mirror:
	http://mindprod.com/jgloss/wrapper.html	J:\mindprod\jgloss\wrapper.html