Writing Scripts in Nashorn - Scripting in Java: Integrating with Groovy and JavaScript - page 147

the Date object, respectively. It contains a getDay() method that returns the day of the
week (0 for Sunday and 6 for Saturday). There are corresponding setter methods such
as setHours() , setDate() , and so on to set the date and time components. There are
another set of getters and setters that work with UTC date and time; their names are
based on the pattern getUTCXxx and setUTCXxx such as getUTCYear() , getUTCHours() ,
setUTCYears() , setUTCHours() , and so on. The getTime() and setTime() methods work
with milliseconds elapsed since midnight January 1970. The Date object contains several
methods named such as toXxxString() to convert the date in a specific string format.
For example, the toDateString() returns a human-readable string format of the date
portion whereas toTimeString() works the same way but on the time portion.
The Date.parse(str) static method parses the specified str considering it as a
date and time in the YYYY-MM-DDTHH:mm:ss.sssZ format and returns the number of
milliseconds elapsed since midnight January 1, 1970 UTC and the parsed date and time.

The Math Object
The Math object contains properties that are mathematical constants and functions.
Table 4-14 lists the properties of the Math object with their descriptions. The properties of
the Math object are self-explanatory; I will not discuss any examples of using them.

Table 4-14. The List of Properties and Methods of the Math Object
Property/Method Description

Math.E The Number value for e, the base of the natural logarithms, which

is approximately 2.7182818284590452354

Math.LN10 The Number value for the natural logarithm of 10, which is

approximately 2.302585092994046

Math.LN2 The Number value for the natural logarithm of 2, which is

approximately 0.6931471805599453

Math.LOG2E

The Number value for the base-2 logarithm of e, which is
approximately 1.4426950408889634

Math.LOG10E The Number value for the base-10 logarithm of e which is

approximately 0.4342944819032518

Math.PI The Number value for p, the ratio of the circumference of a circle

to its diameter, which is approximately 3.1415926535897932

Math.SQRT1_2 The Number value for the square root of 0.50 which is

approximately 0.7071067811865476

Math.SQRT2 The Number value for the square root of 2, which is approximately

1.4142135623730951

Math.abs(x) Returns the absolute value of x. For example, both Math.abs(2)

and Math.abs(-2) return 2

( continued )