刚发现的循环的写法。。。感觉这个更有效率，至少看上去如此

for (int i = SIZE; --i != 0;)
 

汗。。。应该是for (int i = SIZE; i-- != 0;)

我原来都是写

for(int i = SIZE; --i >= 0;)

----------------------------------------------------------------------------

int a = x*y;
int b = y*z;
return a*b - a*b*x;

can be rewritten to:
int a,b;
return (a=x*y)*(b=y*z) - b*a*x;

with this code some stack operations are saved. but it produces very unreadable code in as error prone.
----------------------------------------------------------------------------

To look at the bytecode is always a good idea. A Good plugin for eclipse is this one.
http://asm.objectweb.org/eclipse/index.html