Package org.apache.curator.framework.recipes.atomic

Interface DistributedAtomicNumber<T>

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      AtomicValue<T> add​(T delta)
      Add delta to the current value and return the new value information.
      AtomicValue<T> compareAndSet​(T expectedValue, T newValue)
      Atomically sets the value to the given updated value if the current value == the expected value.
      AtomicValue<T> decrement()
      Subtract 1 from the current value and return the new value information.
      void forceSet​(T newValue)
      Forcibly sets the value of the counter without any guarantees of atomicity.
      AtomicValue<T> get()
      Returns the current value of the counter.
      AtomicValue<T> increment()
      Add 1 to the current value and return the new value information.
      boolean initialize​(T value)
      Atomic values are initially set to the equivalent of NULL in a database.
      AtomicValue<T> subtract​(T delta)
      Subtract delta from the current value and return the new value information.
      AtomicValue<T> trySet​(T newValue)
      Attempt to atomically set the value to the given value.

    • Method Detail

      • get

        AtomicValue<T> get()
            throws java.lang.Exception
        Returns the current value of the counter. NOTE: if the value has never been set, 0 is returned.
        Returns:
        value info
        Throws:
        java.lang.Exception - ZooKeeper errors

      • compareAndSet

        AtomicValue<T> compareAndSet​(T expectedValue,
                             T newValue)
                      throws java.lang.Exception
        Atomically sets the value to the given updated value if the current value == the expected value. Remember to always check AtomicValue.succeeded().
        Parameters:
        expectedValue - the expected value
        newValue - the new value for the counter
        Returns:
        value info
        Throws:
        java.lang.Exception - ZooKeeper errors

      • trySet

        AtomicValue<T> trySet​(T newValue)
               throws java.lang.Exception
        Attempt to atomically set the value to the given value. Remember to always check AtomicValue.succeeded().
        Parameters:
        newValue - the value to set
        Returns:
        value info
        Throws:
        java.lang.Exception - ZooKeeper errors

      • initialize

        boolean initialize​(T value)
            throws java.lang.Exception
        Atomic values are initially set to the equivalent of NULL in a database. Use this method to initialize the value. The value will be set if and only iff the node does not exist.
        Parameters:
        value - the initial value to set
        Returns:
        true if the value was set, false if the node already existed
        Throws:
        java.lang.Exception - ZooKeeper errors

      • forceSet

        void forceSet​(T newValue)
       throws java.lang.Exception
        Forcibly sets the value of the counter without any guarantees of atomicity.
        Parameters:
        newValue - the new value
        Throws:
        java.lang.Exception - ZooKeeper errors

      • increment

        AtomicValue<T> increment()
                  throws java.lang.Exception
        Add 1 to the current value and return the new value information. Remember to always check AtomicValue.succeeded().
        Returns:
        value info
        Throws:
        java.lang.Exception - ZooKeeper errors

      • decrement

        AtomicValue<T> decrement()
                  throws java.lang.Exception
        Subtract 1 from the current value and return the new value information. Remember to always check AtomicValue.succeeded().
        Returns:
        value info
        Throws:
        java.lang.Exception - ZooKeeper errors

      • add

        AtomicValue<T> add​(T delta)
            throws java.lang.Exception
        Add delta to the current value and return the new value information. Remember to always check AtomicValue.succeeded().
        Parameters:
        delta - amount to add
        Returns:
        value info
        Throws:
        java.lang.Exception - ZooKeeper errors

      • subtract

        AtomicValue<T> subtract​(T delta)
                 throws java.lang.Exception
        Subtract delta from the current value and return the new value information. Remember to always check AtomicValue.succeeded().
        Parameters:
        delta - amount to subtract
        Returns:
        value info
        Throws:
        java.lang.Exception - ZooKeeper errors