DN2ID.java revision f0a048d41a13eca4cba405da9403c2469ca3d1ea
/*
* 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 legal-notices/CDDLv1_0.txt
* or http://forgerock.org/license/CDDLv1.0.html.
* 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 legal-notices/CDDLv1_0.txt.
* 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 2006-2010 Sun Microsystems, Inc.
* Portions Copyright 2014-2015 ForgeRock AS
*/
package org.opends.server.backends.pluggable;
import static org.opends.server.backends.pluggable.DnKeyFormat.*;
import static org.opends.server.backends.pluggable.CursorTransformer.*;
import org.forgerock.opendj.ldap.ByteSequence;
import org.forgerock.opendj.ldap.ByteString;
import org.forgerock.opendj.ldap.ByteStringBuilder;
import org.forgerock.util.promise.Function;
import org.opends.server.backends.pluggable.spi.Cursor;
import org.opends.server.backends.pluggable.spi.ReadableTransaction;
import org.opends.server.backends.pluggable.spi.SequentialCursor;
import org.opends.server.backends.pluggable.spi.StorageRuntimeException;
import org.opends.server.backends.pluggable.spi.TreeName;
import org.opends.server.backends.pluggable.spi.WriteableTransaction;
import org.opends.server.types.DN;
import org.opends.server.types.DirectoryException;
/**
* This class represents the DN database, or dn2id, which has one record
* for each entry. The key is the normalized entry DN and the value
* is the entry ID.
*/
class DN2ID extends AbstractDatabaseContainer
{
private static final Function<ByteString, Void, DirectoryException> TO_VOID_KEY =
new Function<ByteString, Void, DirectoryException>()
{
@Override
public Void apply(ByteString value) throws DirectoryException
{
return null;
}
};
private static final CursorTransformer.ValueTransformer<ByteString, ByteString, EntryID, Exception> TO_ENTRY_ID =
new CursorTransformer.ValueTransformer<ByteString, ByteString, EntryID, Exception>()
{
@Override
public EntryID transform(ByteString key, ByteString value) throws Exception
{
return new EntryID(value);
}
};
private final DN baseDN;
/**
* Create a DN2ID instance for the DN database in a given entryContainer.
*
* @param treeName The name of the DN database.
* @param baseDN The base DN of the database.
* @throws StorageRuntimeException If an error occurs in the database.
*/
DN2ID(TreeName treeName, DN baseDN) throws StorageRuntimeException
{
super(treeName);
this.baseDN = baseDN;
}
/**
* Adds a new record into the DN database replacing any existing record having the same DN.
* @param txn a non null database transaction
* @param dn The entry DN, which is the key to the record.
* @param id The entry ID, which is the value of the record.
* @throws StorageRuntimeException If an error occurred while attempting to insert
* the new record.
*/
void put(final WriteableTransaction txn, DN dn, final EntryID id) throws StorageRuntimeException
{
txn.put(getName(), dnToKey(dn), id.toByteString());
}
private ByteString dnToKey(DN dn) {
return dnToDNKey(dn, baseDN.size());
}
/**
* Remove a record from the DN database.
* @param txn a non null database transaction
* @param dn The entry DN, which is the key to the record.
* @return true if the record was removed, false if it was not removed.
* @throws StorageRuntimeException If an error occurred while attempting to remove
* the record.
*/
boolean remove(WriteableTransaction txn, DN dn) throws StorageRuntimeException
{
return txn.delete(getName(), dnToKey(dn));
}
/**
* Fetch the entry ID for a given DN.
* @param txn a non null database transaction
* @param dn The DN for which the entry ID is desired.
* @return The entry ID, or null if the given DN is not in the DN database.
* @throws StorageRuntimeException If an error occurs in the database.
*/
EntryID get(ReadableTransaction txn, DN dn) throws StorageRuntimeException
{
final ByteString value = txn.read(getName(), dnToKey(dn));
return value != null ? new EntryID(value) : null;
}
Cursor<Void, EntryID> openCursor(ReadableTransaction txn, DN dn)
{
return transformKeysAndValues(openCursor0(txn, dn), TO_VOID_KEY, TO_ENTRY_ID);
}
private Cursor<ByteString, ByteString> openCursor0(ReadableTransaction txn, DN dn) {
final Cursor<ByteString, ByteString> cursor = txn.openCursor(getName());
cursor.positionToKey(dnToKey(dn));
return cursor;
}
SequentialCursor<Void, EntryID> openChildrenCursor(ReadableTransaction txn, DN dn)
{
return new ChildrenCursor(openCursor0(txn, dn));
}
SequentialCursor<Void, EntryID> openSubordinatesCursor(ReadableTransaction txn, DN dn) {
return new SubtreeCursor(openCursor0(txn, dn));
}
/**
* Check if two DN have a parent-child relationship.
*
* @param parent
* The potential parent
* @param child
* The potential child of parent
* @return true if child is a direct children of parent, false otherwise.
*/
static boolean isChild(ByteSequence parent, ByteSequence child)
{
if (!child.startsWith(parent))
{
return false;
}
// Immediate children should only have one RDN separator past the parent length
for (int i = child.length(); i >= parent.length(); i--)
{
if (child.byteAt(i) == DN.NORMALIZED_RDN_SEPARATOR && i != parent.length())
{
return false;
}
}
return true;
}
/**
* Decorator overriding the next() behavior to iterate through children of the entry pointed by the given cursor at
* creation.
*/
private static final class ChildrenCursor extends SequentialCursorForwarding {
private final ByteStringBuilder builder;
private final ByteString parentDN;
private boolean cursorOnParent;
ChildrenCursor(Cursor<ByteString, ByteString> delegate)
{
super(delegate);
builder = new ByteStringBuilder(128);
parentDN = delegate.isDefined() ? delegate.getKey() : null;
cursorOnParent = true;
}
@Override
public boolean next()
{
if (cursorOnParent) {
/** Go to the first children */
delegate.next();
cursorOnParent = false;
} else {
/** Go to the next sibling */
delegate.positionToKeyOrNext(nextSibling());
}
return isDefined() && delegate.getKey().startsWith(parentDN);
}
private ByteStringBuilder nextSibling()
{
return builder.clear().append(delegate.getKey()).append((byte) 0x1);
}
}
/**
* Decorator overriding the next() behavior to iterate through subordinates of the entry pointed by the given cursor
* at creation.
*/
private static final class SubtreeCursor extends SequentialCursorForwarding {
private final ByteString baseDN;
SubtreeCursor(Cursor<ByteString, ByteString> delegate)
{
super(delegate);
baseDN = delegate.isDefined() ? delegate.getKey() : null;
}
@Override
public boolean next()
{
return delegate.next() && delegate.getKey().startsWith(baseDN);
}
}
/**
* Decorator allowing to partially overrides methods of a given cursor while keeping the default behavior for other
* methods.
*/
private static class SequentialCursorForwarding implements SequentialCursor<Void, EntryID> {
final Cursor<ByteString, ByteString> delegate;
SequentialCursorForwarding(Cursor<ByteString, ByteString> delegate) {
this.delegate = delegate;
}
@Override
public boolean isDefined()
{
return delegate.isDefined();
}
@Override
public boolean next()
{
return delegate.next();
}
@Override
public Void getKey()
{
return null;
}
@Override
public EntryID getValue()
{
return new EntryID(delegate.getValue());
}
@Override
public void close()
{
delegate.close();
}
}
}