c++ - Memory reservation for java objects -

i know when declaring object instances in c++ so:

object object 

the object constructor called , memory provided object, find when in java object instance doesn't have value until:

object = new object() 

is written. want know when memory provided object. thought both construction , new keyword allocated memory object object = new object() seems redundant. read on oracle's site declaration "reserves" memory , new "allocates" memory, know difference between two.

you need differentiate between space required variable , space required object. bear in mind value of variable reference - pointer in c++. if have:

object x = null; 

then variable x takes enough space reference (usually 4 or 8 bytes). if have:

x = new object(); 

that creates object - value of x reference newly created object. x takes same amount of space before, there's space required object (basically fields, reference type of object, , data synchronization , house-keeping).