EXECUTION

Creation of New Class Instances

12.5

3. This constructor does not begin with an explicit constructor invocation of

another constructor in the same class (using

this

). If this constructor is for a

class other than

Object

, then this constructor will begin with a explicit or

implicit invocation of a superclass constructor (using

super

). Evaluate the

arguments and process that superclass constructor invocation recursively

using these same five steps. If that constructor invocation completes abruptly,

then this procedure completes abruptly for the same reason. Otherwise, con 

tinue with step 4.

4. Execute the instance variable initializers for this class, assigning their values

to the corresponding instance variables, in the left to right order in which they

appear textually in the source code for the class. If execution of any of these

initializers results in an exception, then no further initializers are processed

and this procedure completes abruptly with that same exception. Otherwise,

continue with step 5. (In some early Java implementations, the compiler

incorrectly omitted the code to initialize a field if the field initializer expres 

sion was a constant expression whose value was equal to the default initializa 

tion value for its type.)

5. Execute the rest of the body of this constructor. If that execution completes

abruptly, then this procedure completes abruptly for the same reason. Other 

wise, this procedure completes normally.

In the example:

class Point {

int x, y;

Point() { x = 1; y = 1; }

}

class ColoredPoint extends Point {

int color = 0xFF00FF;

}

class Test {

public static void main(String[] args) {

ColoredPoint cp = new ColoredPoint();

System.out.println(cp.color);

}

}

a new instance of

ColoredPoint

 is created. First, space is allocated for the new

ColoredPoint

, to hold the fields

x

,

y

, and

color

. All these fields are then initial 

ized to their default values (in this case,

0

 for each field). Next, the

ColoredPoint

constructor with no arguments is first invoked. Since

ColoredPoint

 declares no

constructors, a default constructor of the form:

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