Default Member variable values in java

There are several kinds of variables:

• Member variables in a class—these are called fields.
• Variables in a method or block of code—these are called local variables.
• Variables in method declarations—these are called parameters.

Automatic Initialization :

• Field variables (class members) are automatically initialized to default values
• Local variables (method or constructor variables) are not automatically initialized
• Arrays, whether field or local variables, are automatically initialized to the default values of their declared type

Refer : http://www.janeg.ca/scjp/lang/defaults.html