What are java object fields initialized with?

From suns java tutorial

It’s not always necessary to assign a
value when a field is declared. Fields
that are declared but not initialized
will be set to a reasonable default by
the compiler. Generally speaking, this
default will be zero or null,
depending on the data type. Relying on
such default values, however, is
generally considered bad programming
style.

The following chart summarizes the
default values for the above data
types.

Data Type   Default Value (for fields)
byte                    0 
short                   0   
int                     0 
long                    0L 
float                   0.0f 
double                  0.0d 
char                    '\u0000' 
boolean                 false
String (or any object)  null

Local variables are slightly
different; the compiler never assigns
a default value to an uninitialized
local variable. If you cannot
initialize your local variable where
it is declared, make sure to assign it
a value before you attempt to use it.
Accessing an uninitialized local
variable will result in a compile-time
error.

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