Class LoopTool.ManagedIterator

java.lang.Object
org.apache.velocity.tools.generic.LoopTool.ManagedIterator
All Implemented Interfaces:
Iterator
Enclosing class:
LoopTool
public class LoopTool.ManagedIterator extends Object implements 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.
Version:
$Id: LoopTool.java 590893 2007-11-01 04:40:21Z nbubna $
Author:
Nathan Bubna

  • Constructor Details

  • Method Details

    • getName

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

    • get

      public Object get(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 Object next()
      Specified by:
      next in interface 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 Iterator

    • stop

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

    • exclude

      public LoopTool.ManagedIterator exclude(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(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

    • condition

      public LoopTool.ManagedIterator condition(LoopTool.ActionCondition condition)
      Adds a new LoopTool.ActionCondition for this instance to check against the elements in the iterator being managed.
      Parameters:
      condition - condition
      Returns:
      This same LoopTool.ManagedIterator instance

    • sync

      public LoopTool.ManagedIterator sync(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:

    • sync

      public LoopTool.ManagedIterator sync(Object iterable, 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:

    • getLastSyncedValues

      public Map<String,Object> getLastSyncedValues()
      Returns:
      last sync'ed values

    • toString

      public String toString()
      Overrides:
      toString in class Object