程序包 com.alibaba.nacos.common.utils

类 Observable

  • public class Observable
extends java.lang.Object
    Observable utils.
    作者:
    liaochuntao

    • 构造器概要

      构造器 
      构造器 说明
      Observable()  

    • 方法概要

      所有方法 实例方法 具体方法 
      修饰符和类型 方法 说明
      void addObserver​(Observer o)
      Adds an observer to the set of observers for this object, provided that it is not the same as some observer already in the set.
      protected void clearChanged()
      Indicates that this object has no longer changed, or that it has already notified all of its observers of its most recent change, so that the hasChanged method will now return false.
      int countObservers()
      Returns the number of observers of this Observable object.
      void deleteObserver​(Observer o)
      Deletes an observer from the set of observers of this object.
      void deleteObservers()
      Clears the observer list so that this object no longer has any observers.
      boolean hasChanged()
      Tests if this object has changed.
      void notifyObservers()
      If this object has changed, as indicated by the hasChanged method, then notify all of its observers and then call the clearChanged method to indicate that this object has no longer changed.
      protected void setChanged()
      Marks this Observable object as having been changed; the hasChanged method will now return true.

      • 从类继承的方法 java.lang.Object

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

    • 字段详细资料

      • changed

        private transient boolean changed

      • obs

        private transient java.util.Set<Observer> obs

      • observerCnt

        private volatile int observerCnt

    • 构造器详细资料

      • Observable

        public Observable()

    • 方法详细资料

      • addObserver

        public void addObserver​(Observer o)
        Adds an observer to the set of observers for this object, provided that it is not the same as some observer already in the set. The order in which notifications will be delivered to multiple observers is not specified. See the class comment.
        参数:
        o - an observer to be added.
        抛出:
        java.lang.NullPointerException - if the parameter o is null.

      • deleteObserver

        public void deleteObserver​(Observer o)
        Deletes an observer from the set of observers of this object. Passing null to this method will have no effect.
        参数:
        o - the observer to be deleted.

      • notifyObservers

        public void notifyObservers()
        If this object has changed, as indicated by the hasChanged method, then notify all of its observers and then call the clearChanged method to indicate that this object has no longer changed.

        Each observer has its update method called with one argument: this observable object.

      • deleteObservers

        public void deleteObservers()
        Clears the observer list so that this object no longer has any observers.

      • setChanged

        protected void setChanged()
        Marks this Observable object as having been changed; the hasChanged method will now return true.

      • clearChanged

        protected void clearChanged()
        Indicates that this object has no longer changed, or that it has already notified all of its observers of its most recent change, so that the hasChanged method will now return false. This method is called automatically by the notifyObservers methods.
        另请参阅:
        Observable.notifyObservers(), Observable.notifyObservers(java.lang.Object)

      • hasChanged

        public boolean hasChanged()
        Tests if this object has changed.
        返回:
        true if and only if the setChanged method has been called more recently than the clearChanged method on this object; false otherwise.

      • countObservers

        public int countObservers()
        Returns the number of observers of this Observable object.
        返回:
        the number of observers of this object.