Package org.geotools.data

Class Diff

Object
Diff
Direct Known Subclasses:
WFSDiff
public class Diff extends Object
Captures changes made to a FeatureStore prior to being committed.

This is used to simulate the functionality of a database including transaction independence.

Author:
Jody Garnett

  • Field Details

    • nextFID

      public int nextFID
      counter used to genreate the "next" new feature id

    • NULL

      public static final SimpleFeature NULL
      A NullObject used to represent the absence of a SimpleFeature.

      This class is used by TransactionStateDiff as a placeholder to represent features that have been removed. The concept is generally useful and may wish to be taken out as a separate class (used for example to represent deleted rows in a shapefile).

  • Constructor Details

    • Diff

      public Diff()
      Create an empty Diff

    • Diff

      public Diff(Diff other)
      Diff copy.

  • Method Details

    • isEmpty

      public boolean isEmpty()
      Check if modifiedFeatures and addedFeatures are empty.
      Returns:
      true if Diff is empty

    • clear

      public void clear()
      Clear diff - called during rollback.

    • modify

      public void modify(String fid, SimpleFeature f)
      Record a modification to the indicated fid
      Parameters:
      f - replacement feature; null to indicate remove

    • add

      public void add(String fid, SimpleFeature f)

    • addToSpatialIndex

      protected void addToSpatialIndex(SimpleFeature f)

    • remove

      public void remove(String fid)

    • queryIndex

      public List<SimpleFeature> queryIndex(Envelope env)

    • getAddedOrder

      public List<String> getAddedOrder()
      Unmodifieable list indicating the order features were added

    • getModified

      public Map<String,SimpleFeature> getModified()
      Unmodifiable view of modified features. It is imperative that the user manually synchronize on the map when iterating over any of its collection views: 
        Set s = diff.modified2.keySet();  // Needn't be in synchronized block
      ...
  synchronized(diff) {  // Synchronizing on diff, not diff.modified2 or s!
      Iterator i = s.iterator(); // Must be in synchronized block
      while (i.hasNext())
          foo(i.next());
  }
      Failure to follow this advice may result in non-deterministic behavior.

      The returned map will be serializable if the specified map is serializable.

      Returns:
      Map of modified features, null user to represent a removed feature

    • getAdded

      public Map<String,SimpleFeature> getAdded()
      Unmodifiable view of added features. It is imperative that the user manually synchronize on the map when iterating over any of its collection views: 
        Set s = diff.added.keySet();  // Needn't be in synchronized block
      ...
  synchronized(diff) {  // Synchronizing on m, not diff.added or s!
      Iterator i = s.iterator(); // Must be in synchronized block
      while (i.hasNext())
          foo(i.next());
  }
      Failure to follow this advice may result in non-deterministic behavior.

      The returned map will be serializable if the specified map is serializable.

      Returns:
      Map of added features

    • copySTRtreeFrom

      protected Quadtree copySTRtreeFrom(Diff diff)