java.time.jdk8

Class Jdk8Methods

java.lang.Object

java.time.jdk8.Jdk8Methods

public final class Jdk8Methods
extends java.lang.Object

A set of utility methods that provide additional functionality for working with dates and times.

The contents of this class replace functionality available in JDK 8.

Specification for implementors

This is a thread-safe utility class. All returned classes are immutable and thread-safe.

Method Summary

Methods

Modifier and Type	Method and Description
static int	compareInts(int a, int b) Compares two ints.
static int	compareLongs(long a, long b) Compares two longs.
static boolean	equals(java.lang.Object a, java.lang.Object b) Compares two objects.
static int	floorDiv(int a, int b) Returns the floor division.
static long	floorDiv(long a, long b) Returns the floor division.
static int	floorMod(int a, int b) Returns the floor modulus.
static int	floorMod(long a, int b) Returns the floor modulus.
static long	floorMod(long a, long b) Returns the floor modulus.
static <T> T	requireNonNull(T value) Ensures that the argument is non-null.
static <T> T	requireNonNull(T value, java.lang.String parameterName) Ensures that the argument is non-null.
static int	safeAdd(int a, int b) Safely adds two int values.
static long	safeAdd(long a, long b) Safely adds two long values.
static int	safeMultiply(int a, int b) Safely multiply one int by another.
static long	safeMultiply(long a, int b) Safely multiply a long by an int.
static long	safeMultiply(long a, long b) Multiply two values throwing an exception if overflow occurs.
static int	safeSubtract(int a, int b) Safely subtracts one int from another.
static long	safeSubtract(long a, long b) Safely subtracts one long from another.
static int	safeToInt(long value) Safely convert a long to an int.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

requireNonNull

public static <T> T requireNonNull(T value)

Ensures that the argument is non-null.

Type Parameters:

T - the value type

Parameters:

value - the value to check

Returns:

the checked non-null value

Throws:

java.lang.NullPointerException - if the value is null

requireNonNull

public static <T> T requireNonNull(T value,
                   java.lang.String parameterName)

Ensures that the argument is non-null.

Type Parameters:

T - the value type

Parameters:

value - the value to check

parameterName - the name of the parameter

Returns:

the checked non-null value

Throws:

java.lang.NullPointerException - if the value is null

equals

public static boolean equals(java.lang.Object a,
             java.lang.Object b)

Compares two objects.

Parameters:

a - the first value

b - the second value

Returns:

the result

compareInts

public static int compareInts(int a,
              int b)

Compares two ints.

Parameters:

a - the first value

b - the second value

Returns:

the result

compareLongs

public static int compareLongs(long a,
               long b)

Compares two longs.

Parameters:

a - the first value

b - the second value

Returns:

the result

safeAdd

public static int safeAdd(int a,
          int b)

Safely adds two int values.

Parameters:

a - the first value

b - the second value

Returns:

the result

Throws:

java.lang.ArithmeticException - if the result overflows an int

safeAdd

public static long safeAdd(long a,
           long b)

Safely adds two long values.

Parameters:

a - the first value

b - the second value

Returns:

the result

Throws:

java.lang.ArithmeticException - if the result overflows a long

safeSubtract

public static int safeSubtract(int a,
               int b)

Safely subtracts one int from another.

Parameters:

a - the first value

b - the second value to subtract from the first

Returns:

the result

Throws:

java.lang.ArithmeticException - if the result overflows an int

safeSubtract

public static long safeSubtract(long a,
                long b)

Safely subtracts one long from another.

Parameters:

a - the first value

b - the second value to subtract from the first

Returns:

the result

Throws:

java.lang.ArithmeticException - if the result overflows a long

safeMultiply

public static int safeMultiply(int a,
               int b)

Safely multiply one int by another.

Parameters:

a - the first value

b - the second value

Returns:

the result

Throws:

java.lang.ArithmeticException - if the result overflows an int

safeMultiply

public static long safeMultiply(long a,
                int b)

Safely multiply a long by an int.

Parameters:

a - the first value

b - the second value

Returns:

the new total

Throws:

java.lang.ArithmeticException - if the result overflows a long

safeMultiply

public static long safeMultiply(long a,
                long b)

Multiply two values throwing an exception if overflow occurs.

Parameters:

a - the first value

b - the second value

Returns:

the new total

Throws:

java.lang.ArithmeticException - if the result overflows a long

safeToInt

public static int safeToInt(long value)

Safely convert a long to an int.

Parameters:

value - the value to convert

Returns:

the int value

Throws:

java.lang.ArithmeticException - if the result overflows an int

floorDiv

public static long floorDiv(long a,
            long b)

Returns the floor division.

This returns 0 for floorDiv(0, 4).
This returns -1 for floorDiv(-1, 4).
This returns -1 for floorDiv(-2, 4).
This returns -1 for floorDiv(-3, 4).
This returns -1 for floorDiv(-4, 4).
This returns -2 for floorDiv(-5, 4).

Parameters:

a - the dividend

b - the divisor

Returns:

the floor division

floorMod

public static long floorMod(long a,
            long b)

Returns the floor modulus.

This returns 0 for floorMod(0, 4).
This returns 1 for floorMod(-1, 4).
This returns 2 for floorMod(-2, 4).
This returns 3 for floorMod(-3, 4).
This returns 0 for floorMod(-4, 4).

Parameters:

a - the dividend

b - the divisor

Returns:

the floor modulus (positive)

floorMod

public static int floorMod(long a,
           int b)

Returns the floor modulus.

This returns 0 for floorMod(0, 4).
This returns 3 for floorMod(-1, 4).
This returns 2 for floorMod(-2, 4).
This returns 1 for floorMod(-3, 4).
This returns 0 for floorMod(-4, 4).
This returns 3 for floorMod(-5, 4).

Parameters:

a - the dividend

b - the divisor

Returns:

the floor modulus (positive)

floorDiv

public static int floorDiv(int a,
           int b)

Returns the floor division.

This returns 1 for floorDiv(3, 3).
This returns 0 for floorDiv(2, 3).
This returns 0 for floorDiv(1, 3).
This returns 0 for floorDiv(0, 3).
This returns -1 for floorDiv(-1, 3).
This returns -1 for floorDiv(-2, 3).
This returns -1 for floorDiv(-3, 3).
This returns -2 for floorDiv(-4, 3).

Parameters:

a - the dividend

b - the divisor

Returns:

the floor division

floorMod

public static int floorMod(int a,
           int b)

Returns the floor modulus.

This returns 0 for floorMod(3, 3).
This returns 2 for floorMod(2, 3).
This returns 1 for floorMod(1, 3).
This returns 0 for floorMod(0, 3).
This returns 2 for floorMod(-1, 3).
This returns 1 for floorMod(-2, 3).
This returns 0 for floorMod(-3, 3).
This returns 2 for floorMod(-4, 3).

Parameters:

a - the dividend

b - the divisor

Returns:

the floor modulus (positive)