/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE
* or https://OpenDS.dev.java.net/OpenDS.LICENSE.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE. If applicable,
* add the following below this CDDL HEADER, with the fields enclosed
* by brackets "[]" replaced with your own identifying information:
* Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
*
* Copyright 2008 Sun Microsystems, Inc.
*/
package org.opends.server.backends.jeb;
import java.util.List;
import org.opends.server.types.Attribute;
import org.opends.server.types.AttributeType;
import org.opends.server.types.AttributeValue;
import org.opends.server.types.Entry;
import org.opends.server.types.SortKey;
import org.opends.server.types.SortOrder;
/**
* This class defines a data structure that holds a set of attribute values that
* are associated with a sort order for a given entry. Any or all of the
* attribute values may be {@code null} if the entry does not include any values
* for the attribute type targeted by the corresponding sort key.
* <BR><BR>
* This class implements the {@code Comparable} interface and may therefore be
* used to order the elements in components like {@code TreeMap} and
* {@code TreeSet}.
*/
public class SortValues
implements Comparable<SortValues>
{
// The set of sort keys in this sort order.
private AttributeValue[] values;
// The entry ID for the entry associated with this sort values.
private EntryID entryID;
// The sort order for this set of sort values.
private SortOrder sortOrder;
/**
* Creates a new sort values object with the provided information.
*
* @param entryID The entry ID for the entry associated with this set of
* values.
* @param values The attribute values for this sort values.
* @param sortOrder The sort order to use to obtain the necessary values.
*/
public SortValues(EntryID entryID, AttributeValue[] values,
SortOrder sortOrder)
{
this.entryID = entryID;
this.sortOrder = sortOrder;
this.values = values;
}
/**
* Creates a new sort values object with the provided information.
*
* @param entryID The entry ID for the entry associated with this set of
* values.
* @param entry The entry containing the values to extract and use when
* sorting.
* @param sortOrder The sort order to use to obtain the necessary values.
*/
public SortValues(EntryID entryID, Entry entry, SortOrder sortOrder)
{
this.entryID = entryID;
this.sortOrder = sortOrder;
SortKey[] sortKeys = sortOrder.getSortKeys();
values = new AttributeValue[sortKeys.length];
for (int i=0; i < sortKeys.length; i++)
{
SortKey sortKey = sortKeys[i];
AttributeType attrType = sortKey.getAttributeType();
List<Attribute> attrList = entry.getAttribute(attrType);
if (attrList != null)
{
AttributeValue sortValue = null;
// There may be multiple versions of this attribute in the target entry
// (e.g., with different sets of options), and it may also be a
// multivalued attribute. In that case, we need to find the value that
// is the best match for the corresponding sort key (i.e., for sorting
// in ascending order, we want to find the lowest value; for sorting in
// descending order, we want to find the highest value). This is
// handled by the SortKey.compareValues method.
for (Attribute a : attrList)
{
for (AttributeValue v : a)
{
if (sortValue == null)
{
sortValue = v;
}
else if (sortKey.compareValues(v, sortValue) < 0)
{
sortValue = v;
}
}
}
values[i] = sortValue;
}
}
}
/**
* Compares this set of sort values with the provided set of values to
* determine their relative order in a sorted list.
*
* @param sortValues The set of values to compare against this sort values.
* It must also have the same sort order as this set of
* values.
*
* @return A negative value if this sort values object should come before the
* provided values in a sorted list, a positive value if this sort
* values object should come after the provided values in a sorted
* list, or zero if there is no significant difference in their
* relative order.
*/
public int compareTo(SortValues sortValues)
{
SortKey[] sortKeys = sortOrder.getSortKeys();
for (int i=0; i < values.length; i++)
{
int compareValue = sortKeys[i].compareValues(values[i],
sortValues.values[i]);
if (compareValue != 0)
{
return compareValue;
}
}
// If we've gotten here, then we can't tell a difference between the sets of
// sort values, so sort based on entry ID.
long idDifference = (entryID.longValue() - sortValues.entryID.longValue());
if (idDifference < 0)
{
return -1;
}
else if (idDifference > 0)
{
return 1;
}
else
{
return 0;
}
}
/**
* Compares the first element in this set of sort values with the provided
* assertion value to determine whether the assertion value is greater than or
* equal to the initial sort value. This is used during VLV processing to
* find the offset by assertion value.
*
* @param assertionValue The assertion value to compare against the first
* sort value.
*
* @return A negative value if the provided assertion value should come
* before the first sort value, zero if the provided assertion value
* is equal to the first sort value, or a positive value if the
* provided assertion value should come after the first sort value.
*/
public int compareTo(AttributeValue assertionValue)
{
SortKey sortKey = sortOrder.getSortKeys()[0];
return sortKey.compareValues(values[0], assertionValue);
}
/**
* Retrieves a string representation of this sort values object.
*
* @return A string representation of this sort values object.
*/
public String toString()
{
StringBuilder buffer = new StringBuilder();
toString(buffer);
return buffer.toString();
}
/**
* Appends a string representation of this sort values object to the provided
* buffer.
*
* @param buffer The buffer to which the information should be appended.
*/
public void toString(StringBuilder buffer)
{
buffer.append("SortValues(");
SortKey[] sortKeys = sortOrder.getSortKeys();
for (int i=0; i < sortKeys.length; i++)
{
if (i > 0)
{
buffer.append(",");
}
if (sortKeys[i].ascending())
{
buffer.append("+");
}
else
{
buffer.append("-");
}
buffer.append(sortKeys[i].getAttributeType().getNameOrOID());
buffer.append("=");
if (values[i] == null)
{
buffer.append("null");
}
else
{
buffer.append(values[i].getValue().toString());
}
}
buffer.append(", id=");
buffer.append(entryID.toString());
buffer.append(")");
}
/**
* Retrieve the attribute values in this sort values.
*
* @return The array of attribute values for this sort values.
*/
public AttributeValue[] getValues()
{
return values;
}
/**
* Retrieve the entry ID in this sort values.
*
* @return The entry ID for this sort values.
*/
public long getEntryID()
{
return entryID.longValue();
}
}