Package com.unboundid.ldap.sdk

Class EntrySorter

java.lang.Object
com.unboundid.ldap.sdk.EntrySorter
All Implemented Interfaces:
Serializable, Comparator<Entry>
@ThreadSafety(level=COMPLETELY_THREADSAFE) public final class EntrySorter extends Object implements Comparator<Entry>, Serializable
This class provides a mechanism for client-side entry sorting. Sorting may be based on attributes contained in the entry, and may also be based on the hierarchical location of the entry in the DIT. The sorting may be applied to any collection of entries, including the entries included in a SearchResult object.

This class provides a client-side alternative to the use of the ServerSideSortRequestControl. Client-side sorting is most appropriate for small result sets, as it requires all entries to be held in memory at the same time. It is a good alternative to server-side sorting when the overhead of sorting should be distributed across client systems rather than on the server, and in cases in which the target directory server does not support the use of the server-side sort request control.

For best results, a Schema object may be used to provide an indication as to which matching rules should be used to perform the ordering. If no Schema object is provided, then all ordering will be performed using case-ignore string matching.

Example

The following example may be used to obtain a sorted set of search result entries, ordered first by sn and then by givenName, without consideration for hierarchy: 
 SearchResult searchResult = connection.search("dc=example,dc=com",
      SearchScope.SUB, Filter.createEqualityFilter("sn", "Smith"));

 EntrySorter entrySorter = new EntrySorter(false,
      new SortKey("sn"), new SortKey("givenName"));
 SortedSet<Entry> sortedEntries =
     entrySorter.sort(searchResult.getSearchEntries());
See Also:

  • Constructor Details

    • EntrySorter

      public EntrySorter()
      Creates a new entry sorter that will sort entries based only on hierarchy. Superior entries (that is, entries closer to the root of the DIT) will be ordered before subordinate entries. Entries below the same parent will be sorted lexicographically based on their normalized DNs.

    • EntrySorter

      public EntrySorter(boolean sortByHierarchy, @NotNull SortKey... sortKeys)
      Creates a new entry sorter with the provided information.
      Parameters:
      sortByHierarchy - Indicates whether entries should be sorted hierarchically, such that superior entries will be ordered before subordinate entries.
      sortKeys - A list of sort keys that define the order in which attributes should be compared. It may be empty (but never null) if sorting should be done only based on hierarchy.

    • EntrySorter

      public EntrySorter(boolean sortByHierarchy, @Nullable Schema schema, @NotNull SortKey... sortKeys)
      Creates a new entry sorter with the provided information.
      Parameters:
      sortByHierarchy - Indicates whether entries should be sorted hierarchically, such that superior entries will be ordered before subordinate entries.
      schema - The schema to use to make the determination. It may be null if no schema is available.
      sortKeys - A list of sort keys that define the order in which attributes should be compared. It may be empty (but never null) if sorting should be done only based on hierarchy.

    • EntrySorter

      public EntrySorter(boolean sortByHierarchy, @Nullable List<SortKey> sortKeys)
      Creates a new entry sorter with the provided information.
      Parameters:
      sortByHierarchy - Indicates whether entries should be sorted hierarchically, such that superior entries will be ordered before subordinate entries.
      sortKeys - A list of sort keys that define the order in which attributes should be compared. It may be empty or null if sorting should be done only based on hierarchy.

    • EntrySorter

      public EntrySorter(boolean sortByHierarchy, @Nullable Schema schema, @Nullable List<SortKey> sortKeys)
      Creates a new entry sorter with the provided information.
      Parameters:
      sortByHierarchy - Indicates whether entries should be sorted hierarchically, such that superior entries will be ordered before subordinate entries.
      schema - The schema to use to make the determination. It may be null if no schema is available.
      sortKeys - A list of sort keys that define the order in which attributes should be compared. It may be empty or null if sorting should be done only based on hierarchy.

  • Method Details

    • sort

      @NotNull public SortedSet<Entry> sort(@NotNull Collection<? extends Entry> entries)
      Sorts the provided collection of entries according to the criteria defined in this entry sorter.
      Parameters:
      entries - The collection of entries to be sorted.
      Returns:
      A sorted set, ordered in accordance with this entry sorter.

    • compare

      public int compare(@NotNull Entry e1, @NotNull Entry e2)
      Compares the provided entries to determine the order in which they should be placed in a sorted list.
      Specified by:
      compare in interface Comparator<Entry>
      Parameters:
      e1 - The first entry to be compared.
      e2 - The second entry to be compared.
      Returns:
      A negative value if the first entry should be ordered before the second, a positive value if the first entry should be ordered after the second, or zero if the entries should have an equivalent order.

    • hashCode

      public int hashCode()
      Retrieves a hash code for this entry sorter.
      Overrides:
      hashCode in class Object
      Returns:
      A hash code for this entry sorter.

    • equals

      public boolean equals(@Nullable Object o)
      Indicates whether the provided object is equal to this entry sorter.
      Specified by:
      equals in interface Comparator<Entry>
      Overrides:
      equals in class Object
      Parameters:
      o - The object for which to make the determination.
      Returns:
      true if the provided object is equal to this entry sorter, or false if not.

    • toString

      @NotNull public String toString()
      Retrieves a string representation of this entry sorter.
      Overrides:
      toString in class Object
      Returns:
      A string representation of this entry sorter.

    • toString

      public void toString(@NotNull StringBuilder buffer)
      Appends a string representation of this entry sorter to the provided buffer.
      Parameters:
      buffer - The buffer to which the string representation should be appended.