Package org.apache.velocity.tools.generic

Class LoopTool.ManagedIterator

  • All Implemented Interfaces:
    java.util.Iterator
    Enclosing class:
    LoopTool
    public class LoopTool.ManagedIterator
extends java.lang.Object
implements java.util.Iterator
    Iterator implementation that wraps a standard Iterator and allows it to be prematurely stopped, skipped ahead, and associated with a name for advanced nested loop control. This also allows a arbitrary LoopTool.ActionConditions to be added in order to have it automatically skip over or stop before certain elements in the iterator.

    • Constructor Detail

      • ManagedIterator

        public ManagedIterator​(java.lang.String name,
                       java.util.Iterator iterator,
                       LoopTool owner)

    • Method Detail

      • getName

        public java.lang.String getName()
        Returns:
        the name of this instance.

      • isFirst

        public boolean isFirst()
        Returns:
        true if either 0 or 1 elements have been returned by next().

      • isLast

        public boolean isLast()
        Returns:
        true if the last element returned by next() is the last element available in the iterator being managed which satisfies any/all LoopTool.ActionConditions set for this instance. Otherwise, returns false.

      • getFirst

        public boolean getFirst()
        Returns:
        the result of isFirst(). Exists to allow $loop.this.first syntax.

      • getLast

        public boolean getLast()
        Returns:
        the result of isLast(). Exists to allow $loop.this.last syntax.

      • hasNext

        public boolean hasNext()
        Specified by:
        hasNext in interface java.util.Iterator
        Returns:
        true if there are more elements in the iterator being managed by this instance which satisfy all the LoopTool.ActionConditions set for this instance. Returns false if there are no more valid elements available.

      • getHasNext

        public boolean getHasNext()
        Returns:
        the result of hasNext(). Exists to allow $loop.this.hasNext syntax.

      • isSyncedWith

        public boolean isSyncedWith​(java.lang.String name)
        Parameters:
        name - syn'ed iterator name
        Returns:
        true if this ManagedIterator has a sync'ed iterator with the specified name.

      • get

        public java.lang.Object get​(java.lang.String name)
        Parameters:
        name - iterator name
        Returns:
        the parallel value from the specified sync'ed iterator. If no sync'ed iterator exists with that name or that iterator is finished, this will return null.

      • getCount

        public int getCount()
        Returns:
        the number of elements returned by next() so far.

      • getIndex

        public int getIndex()
        Returns:
        the 0-based index of the current item.

      • next

        public java.lang.Object next()
        Specified by:
        next in interface java.util.Iterator
        Returns:
        the next element that meets the set LoopTool.ActionConditions (if any) in the iterator being managed. If there are none left, then this will throw a NoSuchElementException.

      • remove

        public void remove()
        This operation is unsupported.
        Specified by:
        remove in interface java.util.Iterator

      • stop

        public void stop()
        Stops this iterator from doing any further iteration.

      • exclude

        public LoopTool.ManagedIterator exclude​(java.lang.Object compare)
        Directs this instance to completely exclude any elements equal to the specified Object.
        Parameters:
        compare - value to exclude
        Returns:
        This same LoopTool.ManagedIterator instance

      • stop

        public LoopTool.ManagedIterator stop​(java.lang.Object compare)
        Directs this instance to stop iterating immediately prior to any element equal to the specified Object.
        Parameters:
        compare - value to stop at
        Returns:
        This same LoopTool.ManagedIterator instance

      • sync

        public LoopTool.ManagedIterator sync​(java.lang.Object iterable)

        Adds another iterator to be kept in sync with the one being managed by this instance. The values of the parallel iterator can be retrieved from the LoopTool under the name s"synced" (e.g. $loop.synced or $loop.get('synced')) and are automatically updated for each iteration by this instance.

        NOTE: if you are sync'ing multiple iterators with the same managed iterator, you must use sync(Object,String) or else your the later iterators will simply replace the earlier ones under the default 'synced' key.

        Parameters:
        iterable - Iterator to synchronize with
        Returns:
        This same LoopTool.ManagedIterator instance
        See Also:
        LoopTool.SyncedIterator, get(String)

      • sync

        public LoopTool.ManagedIterator sync​(java.lang.Object iterable,
                                     java.lang.String name)
        Adds another iterator to be kept in sync with the one being managed by this instance. The values of the parallel iterator can be retrieved from the LoopTool under the name specified here (e.g. $loop.name or $loop.get('name')) and are automatically updated for each iteration by this instance.
        Parameters:
        iterable - iterator to synchronize with
        name - loop name
        Returns:
        This same LoopTool.ManagedIterator instance
        See Also:
        LoopTool.SyncedIterator, get(String)

      • getLastSyncedValues

        public java.util.Map<java.lang.String,​java.lang.Object> getLastSyncedValues()
        Returns:
        last sync'ed values

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object