Package io.reactivex.rxjava3.internal.util

Class BackpressureHelper

  • public final class BackpressureHelper
extends java.lang.Object
    Utility class to help with backpressure-related operations such as request aggregation.

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      private BackpressureHelper()
      Utility class.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static long add​(@NonNull java.util.concurrent.atomic.AtomicLong requested, long n)
      Atomically adds the positive value n to the requested value in the AtomicLong and caps the result at Long.MAX_VALUE and returns the previous value.
      static long addCancel​(@NonNull java.util.concurrent.atomic.AtomicLong requested, long n)
      Atomically adds the positive value n to the requested value in the AtomicLong and caps the result at Long.MAX_VALUE and returns the previous value and considers Long.MIN_VALUE as a cancel indication (no addition then).
      static long addCap​(long a, long b)
      Adds two long values and caps the sum at Long.MAX_VALUE.
      static long multiplyCap​(long a, long b)
      Multiplies two long values and caps the product at Long.MAX_VALUE.
      static long produced​(@NonNull java.util.concurrent.atomic.AtomicLong requested, long n)
      Atomically subtract the given number (positive, not validated) from the target field unless it contains Long.MAX_VALUE.
      static long producedCancel​(@NonNull java.util.concurrent.atomic.AtomicLong requested, long n)
      Atomically subtract the given number (positive, not validated) from the target field if it doesn't contain Long.MIN_VALUE (indicating some cancelled state) or Long.MAX_VALUE (unbounded mode).

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • BackpressureHelper

        private BackpressureHelper()
        Utility class.

    • Method Detail

      • addCap

        public static long addCap​(long a,
                          long b)
        Adds two long values and caps the sum at Long.MAX_VALUE.
        Parameters:
        a - the first value
        b - the second value
        Returns:
        the sum capped at Long.MAX_VALUE

      • multiplyCap

        public static long multiplyCap​(long a,
                               long b)
        Multiplies two long values and caps the product at Long.MAX_VALUE.
        Parameters:
        a - the first value
        b - the second value
        Returns:
        the product capped at Long.MAX_VALUE

      • add

        public static long add​(@NonNull
                       @NonNull java.util.concurrent.atomic.AtomicLong requested,
                       long n)
        Atomically adds the positive value n to the requested value in the AtomicLong and caps the result at Long.MAX_VALUE and returns the previous value.
        Parameters:
        requested - the AtomicLong holding the current requested value
        n - the value to add, must be positive (not verified)
        Returns:
        the original value before the add

      • addCancel

        public static long addCancel​(@NonNull
                             @NonNull java.util.concurrent.atomic.AtomicLong requested,
                             long n)
        Atomically adds the positive value n to the requested value in the AtomicLong and caps the result at Long.MAX_VALUE and returns the previous value and considers Long.MIN_VALUE as a cancel indication (no addition then).
        Parameters:
        requested - the AtomicLong holding the current requested value
        n - the value to add, must be positive (not verified)
        Returns:
        the original value before the add

      • produced

        public static long produced​(@NonNull
                            @NonNull java.util.concurrent.atomic.AtomicLong requested,
                            long n)
        Atomically subtract the given number (positive, not validated) from the target field unless it contains Long.MAX_VALUE.
        Parameters:
        requested - the target field holding the current requested amount
        n - the produced element count, positive (not validated)
        Returns:
        the new amount

      • producedCancel

        public static long producedCancel​(@NonNull
                                  @NonNull java.util.concurrent.atomic.AtomicLong requested,
                                  long n)
        Atomically subtract the given number (positive, not validated) from the target field if it doesn't contain Long.MIN_VALUE (indicating some cancelled state) or Long.MAX_VALUE (unbounded mode).
        Parameters:
        requested - the target field holding the current requested amount
        n - the produced element count, positive (not validated)
        Returns:
        the new amount