001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 * 019 */ 020package org.apache.directory.server.xdbm.search.impl; 021 022 023import org.apache.directory.api.ldap.model.exception.LdapException; 024import org.apache.directory.api.ldap.model.filter.BranchNode; 025import org.apache.directory.api.ldap.model.filter.ExprNode; 026import org.apache.directory.server.core.api.partition.PartitionTxn; 027import org.apache.directory.server.xdbm.search.Optimizer; 028 029 030/** 031 * A do nothing optimizer which labels all nodes with <code> 032 * BigInteger.valueOf( Integer.MAX_VALUE ) </code>, instead of actually 033 * taking scan counts. 034 * 035 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 036 */ 037public class NoOpOptimizer implements Optimizer 038{ 039 /** the maximum size for a count Integer.MAX_VALUE as a BigInteger */ 040 private static final Long MAX = Long.MAX_VALUE; 041 042 043 public Long annotate( PartitionTxn partitionTxn, ExprNode node ) throws LdapException 044 { 045 if ( node.isLeaf() ) 046 { 047 node.set( DefaultOptimizer.COUNT_ANNOTATION, MAX ); 048 return MAX; 049 } 050 051 BranchNode bnode = ( BranchNode ) node; 052 053 if ( bnode.getChildren().isEmpty() ) 054 { 055 bnode.set( DefaultOptimizer.COUNT_ANNOTATION, MAX ); 056 return MAX; 057 } 058 059 final int limit = bnode.getChildren().size(); 060 for ( int ii = 0; ii < limit; ii++ ) 061 { 062 ExprNode child = bnode.getChildren().get( ii ); 063 if ( child.isLeaf() ) 064 { 065 child.set( DefaultOptimizer.COUNT_ANNOTATION, MAX ); 066 } 067 else 068 { 069 annotate( partitionTxn, child ); 070 } 071 } 072 073 bnode.set( DefaultOptimizer.COUNT_ANNOTATION, MAX ); 074 return MAX; 075 } 076}