Java 右侧小于等于的语句

Question

Here's a line from a large Java program which compiles without errors. I'm unable to understand how the <= operator is being used on the right side of assignment statement:

converged = measure.distance(centroid.getLengthSquared(), centroid, getCenter()) <= convergenceDelta;

Is this some obscure Java feature?

Answer 1

No, it's not.

As you will see converged will be of boolean type.

It will be exactly the same as saying

boolean foo = 2 <= 3;

So, probably in your code measure.distance(centroid.getLengthSquared(), centroid, getCenter()) returns a number which is then compared using the relational <= operator with convergenceDelta;. The result will be true or false , a boolean value which will be saved at converged .

Answer 2

Not at all. <= and the other relational operators return boolean values. If converged is a boolean variable, you can assign that value to it.

Answer 3

It is setting converged to the truth statement of the distance being less than or equal to the value on the variable convergenceDelta.

Answer 4

<= is a binary operator like any other. The value of it is true if LHS <= RHS, and false if not.

So in this case, if the distance is less than the convergence delta it's considered to have converged.