Package org.apache.openjpa.util

Class AbstractLRSProxyMap<K,​V>

  • All Implemented Interfaces:
    java.util.function.Predicate, java.util.Map<K,​V>, ChangeTracker, LRSProxy, MapChangeTracker, Proxy
    public abstract class AbstractLRSProxyMap<K,​V>
extends java.lang.Object
implements java.util.Map<K,​V>, LRSProxy, MapChangeTracker, java.util.function.Predicate
    A map proxy designed for maps backed by extremely large result sets in which each call to get(java.lang.Object) or containsKey(java.lang.Object) may perform a database query. Changes to the map are tracked through a ChangeTracker. This map has the following limitations:
    • The size method may return Integer.MAX_VALUE.
    • Null keys and values are not supported.
    Author:
    Abe White

    • Nested Class Summary

      • Nested classes/interfaces inherited from interface java.util.Map

        java.util.Map.Entry<K extends java.lang.Object,​V extends java.lang.Object>

    • Constructor Summary

      Constructors 
      Constructor Description
      AbstractLRSProxyMap​(java.lang.Class<K> keyType, java.lang.Class<V> valueType)  

    • Method Summary

      All Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      void added​(java.lang.Object key, java.lang.Object val)
      Record that the given entry was added to the map.
      void changed​(java.lang.Object key, java.lang.Object orig, java.lang.Object val)
      Record that the given entry was altered.
      void clear()  
      boolean containsKey​(java.lang.Object key)  
      boolean containsValue​(java.lang.Object val)  
      java.lang.Object copy​(java.lang.Object orig)
      Return an unproxied copy of the given instance.
      protected abstract int count()
      Return the number of entries in the map, or Integer.MAX_VALUE.
      java.util.Set<java.util.Map.Entry<K,​V>> entrySet()  
      V get​(java.lang.Object key)  
      java.util.Collection getAdded()
      Return the collection of values that need to be added to the managed container.
      java.util.Collection getChanged()
      Return the set of elements that have changed.
      ChangeTracker getChangeTracker()
      Return the change tracker for this proxy, or null if none.
      int getNextSequence()
      The next element sequence value for this proxy at load time.
      OpenJPAStateManager getOwner()
      Return the owning object.
      int getOwnerField()
      Return the owning field index.
      java.util.Collection getRemoved()
      Return the set of values that need to be removed from the managed container.
      boolean getTrackKeys()
      Whether to track keys or values.
      protected abstract boolean hasKey​(java.lang.Object key)
      Return whether the given key exists in the map.
      protected abstract boolean hasValue​(java.lang.Object value)
      Return whether the given value exists in the map.
      boolean isEmpty()  
      boolean isTracking()
      Return true if this tracker has an up-to-date view of all the changes to the container it is managing.
      protected abstract java.util.Iterator<?> itr()
      Implement this method to return an iterator over the entries in the map.
      protected abstract java.util.Collection<K> keys​(java.lang.Object value)
      Return all keys for the given value.
      java.util.Set<K> keySet()  
      V put​(K key, V value)  
      void putAll​(java.util.Map<? extends K,​? extends V> m)  
      V remove​(java.lang.Object key)  
      void removed​(java.lang.Object key, java.lang.Object val)
      Record that the given entry was removed from the map.
      void setNextSequence​(int seq)
      The maximum element sequence value for this proxy at load time.
      void setOwner​(OpenJPAStateManager sm, int field)
      Reset the state of the proxy, and set the owning instance of the proxy and the name of the field it is assigned to.
      void setTrackKeys​(boolean keys)
      Whether to track keys or values.
      int size()  
      void startTracking()
      Reset the state of the change tracker, and turn change tracking back on if it has been disabled.
      void stopTracking()
      Tell the tracker to stop tracking changes for its container.
      boolean test​(java.lang.Object obj)  
      protected abstract V value​(java.lang.Object key)
      Return the value of the given key.
      java.util.Collection<V> values()  
      protected java.lang.Object writeReplace()  

      • Methods inherited from class java.lang.Object

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

      • Methods inherited from interface java.util.Map

        compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

      • Methods inherited from interface java.util.function.Predicate

        and, negate, or

    • Constructor Detail

      • AbstractLRSProxyMap

        public AbstractLRSProxyMap​(java.lang.Class<K> keyType,
                           java.lang.Class<V> valueType)

    • Method Detail

      • setOwner

        public void setOwner​(OpenJPAStateManager sm,
                     int field)
        Description copied from interface: Proxy
        Reset the state of the proxy, and set the owning instance of the proxy and the name of the field it is assigned to. Set to null to indicate that the proxy is no longer managed.
        Specified by:
        setOwner in interface Proxy

      • getOwnerField

        public int getOwnerField()
        Description copied from interface: Proxy
        Return the owning field index.
        Specified by:
        getOwnerField in interface Proxy

      • getChangeTracker

        public ChangeTracker getChangeTracker()
        Description copied from interface: Proxy
        Return the change tracker for this proxy, or null if none.
        Specified by:
        getChangeTracker in interface Proxy

      • copy

        public java.lang.Object copy​(java.lang.Object orig)
        Description copied from interface: Proxy
        Return an unproxied copy of the given instance. This method is used by proxy managers to create backup values for use in rollback.
        Specified by:
        copy in interface Proxy

      • size

        public int size()
        Specified by:
        size in interface java.util.Map<K,​V>

      • isEmpty

        public boolean isEmpty()
        Specified by:
        isEmpty in interface java.util.Map<K,​V>

      • containsKey

        public boolean containsKey​(java.lang.Object key)
        Specified by:
        containsKey in interface java.util.Map<K,​V>

      • containsValue

        public boolean containsValue​(java.lang.Object val)
        Specified by:
        containsValue in interface java.util.Map<K,​V>

      • get

        public V get​(java.lang.Object key)
        Specified by:
        get in interface java.util.Map<K,​V>

      • put

        public V put​(K key,
             V value)
        Specified by:
        put in interface java.util.Map<K,​V>

      • putAll

        public void putAll​(java.util.Map<? extends K,​? extends V> m)
        Specified by:
        putAll in interface java.util.Map<K,​V>

      • remove

        public V remove​(java.lang.Object key)
        Specified by:
        remove in interface java.util.Map<K,​V>

      • clear

        public void clear()
        Specified by:
        clear in interface java.util.Map<K,​V>

      • keySet

        public java.util.Set<K> keySet()
        Specified by:
        keySet in interface java.util.Map<K,​V>

      • values

        public java.util.Collection<V> values()
        Specified by:
        values in interface java.util.Map<K,​V>

      • entrySet

        public java.util.Set<java.util.Map.Entry<K,​V>> entrySet()
        Specified by:
        entrySet in interface java.util.Map<K,​V>

      • writeReplace

        protected java.lang.Object writeReplace()
                                 throws java.io.ObjectStreamException
        Throws:
        java.io.ObjectStreamException

      • hasKey

        protected abstract boolean hasKey​(java.lang.Object key)
        Return whether the given key exists in the map.

      • hasValue

        protected abstract boolean hasValue​(java.lang.Object value)
        Return whether the given value exists in the map.

      • keys

        protected abstract java.util.Collection<K> keys​(java.lang.Object value)
        Return all keys for the given value.

      • value

        protected abstract V value​(java.lang.Object key)
        Return the value of the given key.

      • itr

        protected abstract java.util.Iterator<?> itr()
        Implement this method to return an iterator over the entries in the map. Each returned object must implement the Map.Entry interface. This method may be invoked multiple times. The iterator does not have to support the Iterator.remove() method, and may implement Closeable.

      • count

        protected abstract int count()
        Return the number of entries in the map, or Integer.MAX_VALUE.

      • test

        public boolean test​(java.lang.Object obj)
        Specified by:
        test in interface java.util.function.Predicate<K>

      • isTracking

        public boolean isTracking()
        Description copied from interface: ChangeTracker
        Return true if this tracker has an up-to-date view of all the changes to the container it is managing.
        Specified by:
        isTracking in interface ChangeTracker

      • startTracking

        public void startTracking()
        Description copied from interface: ChangeTracker
        Reset the state of the change tracker, and turn change tracking back on if it has been disabled.
        Specified by:
        startTracking in interface ChangeTracker

      • stopTracking

        public void stopTracking()
        Description copied from interface: ChangeTracker
        Tell the tracker to stop tracking changes for its container.
        Specified by:
        stopTracking in interface ChangeTracker

      • getTrackKeys

        public boolean getTrackKeys()
        Description copied from interface: MapChangeTracker
        Whether to track keys or values. Defaults to keys. If you set to values, it is assumed there is a 1-1 correlation between keys and values in this map.
        Specified by:
        getTrackKeys in interface MapChangeTracker

      • setTrackKeys

        public void setTrackKeys​(boolean keys)
        Description copied from interface: MapChangeTracker
        Whether to track keys or values. Defaults to keys. If you set to values, it is assumed there is a 1-1 correlation between keys and values in this map.
        Specified by:
        setTrackKeys in interface MapChangeTracker

      • getAdded

        public java.util.Collection getAdded()
        Description copied from interface: ChangeTracker
        Return the collection of values that need to be added to the managed container.
        Specified by:
        getAdded in interface ChangeTracker

      • getRemoved

        public java.util.Collection getRemoved()
        Description copied from interface: ChangeTracker
        Return the set of values that need to be removed from the managed container.
        Specified by:
        getRemoved in interface ChangeTracker

      • getChanged

        public java.util.Collection getChanged()
        Description copied from interface: ChangeTracker
        Return the set of elements that have changed. In maps, this marks a possible change in value for a key. In collections, this marks an element that has been removed and re-added.
        Specified by:
        getChanged in interface ChangeTracker

      • added

        public void added​(java.lang.Object key,
                  java.lang.Object val)
        Description copied from interface: MapChangeTracker
        Record that the given entry was added to the map.
        Specified by:
        added in interface MapChangeTracker

      • removed

        public void removed​(java.lang.Object key,
                    java.lang.Object val)
        Description copied from interface: MapChangeTracker
        Record that the given entry was removed from the map.
        Specified by:
        removed in interface MapChangeTracker

      • changed

        public void changed​(java.lang.Object key,
                    java.lang.Object orig,
                    java.lang.Object val)
        Description copied from interface: MapChangeTracker
        Record that the given entry was altered.
        Specified by:
        changed in interface MapChangeTracker

      • getNextSequence

        public int getNextSequence()
        Description copied from interface: ChangeTracker
        The next element sequence value for this proxy at load time. If the data store keeps this proxy's data in sequence order but allows holes for removed objects, the implementation can set the next sequence at load time, then retrieve it and start from there for added objects at flush time. This value is set back to 0 if the proxy stops tracking changes. For ordered proxies, it is set to the proxy's size when the proxy starts tracking changes again.
        Specified by:
        getNextSequence in interface ChangeTracker

      • setNextSequence

        public void setNextSequence​(int seq)
        Description copied from interface: ChangeTracker
        The maximum element sequence value for this proxy at load time. If the data store keeps this proxy's data in sequence order but allows holes for removed objects, the implementation can set the next sequence at load time, then retrieve it and start from there for added objects at flush time. This value is set back to 0 if the proxy stops tracking changes. For ordered proxies, it is set to the proxy's size when the proxy starts tracking changes again.
        Specified by:
        setNextSequence in interface ChangeTracker