Java Double.compare() is a static method in the Java Double class that compares two Java double values for order. It returns a negative value if the first value is smaller, zero if they are equal, and a positive value if the first value is larger. Introduced in Java 2004 with Java 5, compare() is used for precise comparisons in applications requiring exact ordering of floating-point numbers, such as in sorting or ranking algorithms.

https://docs.oracle.com/javase/8/docs/api/java/lang/Double.html