15.11.4

Runtime Evaluation of Method Invocation

EXPRESSIONS

So, for example, in:

class Test {

public static void main(String[] args) {

String s = "one";

if (s.startsWith(s = "two"))

System.out.println("oops");

}

}

the occurrence of

s

 before  

.startsWith

  is evaluated first, before the argument

expression

s="two"

. Therefore, a reference to the string

"one"

 is remembered as

the target reference before the local variable s is changed to refer to the string

"two"

. As a result, the

startsWith

 method ( 20.12.20) is invoked for target

object

"one"

 with argument

"two"

, so the result of the invocation is

false

, as the

string

"one"

 does not start with

"two"

. It follows that the test program does not

print  

oops

 .

15.11.4.9

Example: Overriding

In the example:

class Point {

final int EDGE = 20;

int x, y;

void move(int dx, int dy) {

x += dx; y += dy;

if (Math.abs(x) >= EDGE || Math.abs(y) >= EDGE)

clear();

}

void clear() {

System.out.println("\tPoint clear");

x = 0; y = 0;

}

}

class ColoredPoint extends Point {

int color;

void clear() {

System.out.println("\tColoredPoint clear");

super.clear();

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