Package io.servicetalk.concurrent.internal

Class FlowControlUtils

java.lang.Object

io.servicetalk.concurrent.internal.FlowControlUtils

public final class FlowControlUtils
extends Object

A set of utility methods for safe math operations to prevent overflow.

Method Summary

Modifier and Type	Method	Description
static int	addWithOverflowProtection(int x, int y)	Adds two positive ints and returns Integer.MAX_VALUE if overflow occurs.
static long	addWithOverflowProtection(long x, long y)	Adds two positive longs and returns Long.MAX_VALUE if overflow occurs.
static long	addWithOverflowProtectionIfGtEqNegativeOne(long x, long y)	If x is >=-1 this method behaves the same as addWithOverflowProtection(long, long).
static int	addWithOverflowProtectionIfNotNegative(int x, int y)	If x is non-negative this method behaves the same as addWithOverflowProtection(int, int).
static long	addWithOverflowProtectionIfNotNegative(long x, long y)	If x is non-negative this method behaves the same as addWithOverflowProtection(long, long).
static int	addWithOverflowProtectionIfPositive(int x, int y)	If x is positive this method behaves the same as addWithOverflowProtection(int, int).
static long	addWithOverflowProtectionIfPositive(long x, long y)	If x is positive this method behaves the same as addWithOverflowProtection(long, long).
static int	addWithUnderOverflowProtection(int x, int y)	Add two longs and prevent [under|over]flow which is defined as if both x and y have the same sign but the result of x + y has a different sign.
static long	addWithUnderOverflowProtection(long x, long y)	Add two longs and prevent [under|over]flow which is defined as if both x and y have the same sign but the result of x + y has a different sign.

Methods inherited from class java.lang.Object

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

Method Details

addWithOverflowProtectionIfGtEqNegativeOne

public static long addWithOverflowProtectionIfGtEqNegativeOne(long x,
 long y)

If x is >=-1 this method behaves the same as addWithOverflowProtection(long, long). If x is <-1 then x is returned.

Parameters:

x - first value (may be negative).

y - second value (should be positive).

Returns:

The result of x+y or Long.MAX_VALUE if overflow occurs, or x if x<-1.

addWithOverflowProtectionIfNotNegative

public static long addWithOverflowProtectionIfNotNegative(long x,
 long y)

If x is non-negative this method behaves the same as addWithOverflowProtection(long, long). If x is negative then x is returned.

Parameters:

x - first value (may be negative).

y - second value (should be positive).

Returns:

The result of x+y or Long.MAX_VALUE if overflow occurs, or x if x is negative.

addWithOverflowProtectionIfNotNegative

public static int addWithOverflowProtectionIfNotNegative(int x,
 int y)

If x is non-negative this method behaves the same as addWithOverflowProtection(int, int). If x is negative then x is returned.

Parameters:

x - first value (may be negative).

y - second value (should be positive).

Returns:

The result of x+y or Integer.MAX_VALUE if overflow occurs, or x if x is negative.

addWithOverflowProtectionIfPositive

public static int addWithOverflowProtectionIfPositive(int x,
 int y)

If x is positive this method behaves the same as addWithOverflowProtection(int, int). If x is negative or zero then x is returned.

Parameters:

x - first value (may be negative).

y - second value (should be positive).

Returns:

The result of x+y or Integer.MAX_VALUE if overflow occurs, or x if x is negative.

addWithOverflowProtectionIfPositive

public static long addWithOverflowProtectionIfPositive(long x,
 long y)

If x is positive this method behaves the same as addWithOverflowProtection(long, long). If x is negative or zero then x is returned.

Parameters:

x - first value (may be negative).

y - second value (should be positive).

Returns:

The result of x+y or Long.MAX_VALUE if overflow occurs, or x if x is negative.

addWithOverflowProtection

public static long addWithOverflowProtection(long x,
 long y)

Adds two positive longs and returns Long.MAX_VALUE if overflow occurs.

Parameters:

x - first value (should be positive).

y - second value (should be positive).

Returns:

The result of x+y or Long.MAX_VALUE if overflow occurs.

addWithOverflowProtection

public static int addWithOverflowProtection(int x,
 int y)

Adds two positive ints and returns Integer.MAX_VALUE if overflow occurs.

Parameters:

x - first value (should be positive).

y - second value (should be positive).

Returns:

The result of x+y or Integer.MAX_VALUE if overflow occurs.

addWithUnderOverflowProtection

public static long addWithUnderOverflowProtection(long x,
 long y)

Add two longs and prevent [under|over]flow which is defined as if both x and y have the same sign but the result of x + y has a different sign.

Parameters:

x - first value.

y - second value.

Returns:

• x + y if no overflow
• Long.MAX_VALUE if overflow in the positive direction
• Long.MIN_VALUE if otherwise in the negative direction

addWithUnderOverflowProtection

public static int addWithUnderOverflowProtection(int x,
 int y)

Add two longs and prevent [under|over]flow which is defined as if both x and y have the same sign but the result of x + y has a different sign.

Parameters:

x - first value.

y - second value.

Returns:

• x + y if no overflow
• Integer.MAX_VALUE if overflow in the positive direction
• Integer.MIN_VALUE if otherwise in the negative direction