| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.vxquery.xmlparser; |
| |
| public class TreeNodeIdProvider implements ITreeNodeIdProvider { |
| |
| private final short partitionDataSource; |
| private final short dataSouceScanId; |
| private final byte dataSourceBits; |
| private short currentId; |
| |
| public TreeNodeIdProvider(short partitionDataSource, short dataSouceScanId, short totalDataSources) { |
| this.partitionDataSource = partitionDataSource; |
| this.dataSouceScanId = dataSouceScanId; |
| this.dataSourceBits = getBitsNeeded(totalDataSources); |
| currentId = 0; |
| } |
| |
| public TreeNodeIdProvider(short partition) { |
| this.partitionDataSource = partition; |
| dataSouceScanId = 0; |
| dataSourceBits = 0; |
| currentId = 0; |
| } |
| |
| public int getId() { |
| int p = partitionDataSource; |
| int dssi = dataSouceScanId; |
| return (p << 16) | (dssi << (16 - dataSourceBits)) | currentId++; |
| } |
| |
| private byte getBitsNeeded(int number) { |
| byte count = 0; |
| while (number > 0) { |
| count++; |
| number = number >> 1; |
| } |
| return count; |
| } |
| } |