| /* |
| * 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.jackrabbit.oak.segment; |
| |
| import java.util.Iterator; |
| |
| import com.google.common.collect.AbstractIterator; |
| |
| import org.jetbrains.annotations.NotNull; |
| |
| /** |
| * An immutable record table. It is initialized at construction time and can |
| * never be changed afterwards. |
| * <p> |
| * This implementation is trivially thread-safe. |
| */ |
| class ImmutableRecordNumbers implements RecordNumbers { |
| |
| @NotNull |
| private final int[] offsets; |
| |
| @NotNull |
| private final byte[] type; |
| |
| /** |
| * Create a new instance based on arrays for the offsets and types. |
| * <p> |
| * <em>Note:</em> for performance reasons these arrays are directly referenced |
| * by this class and must not anymore be modified from other places. |
| * |
| * @param offsets Offsets per position. -1 if not mapped. |
| * @param type Types per position. Not defined if not mapped. |
| */ |
| public ImmutableRecordNumbers(@NotNull int[] offsets, @NotNull byte[] type) { |
| this.offsets = offsets; |
| this.type = type; |
| } |
| |
| |
| @Override |
| public int getOffset(int recordNumber) { |
| if (recordNumber < offsets.length) { |
| return offsets[recordNumber]; |
| } else { |
| return -1; |
| } |
| } |
| |
| @NotNull |
| @Override |
| public Iterator<Entry> iterator() { |
| return new AbstractIterator<Entry>() { |
| private int pos = -1; |
| @Override |
| protected Entry computeNext() { |
| while (++pos < offsets.length && offsets[pos] < 0) { } |
| if (pos < offsets.length) { |
| return new Entry() { |
| @Override |
| public int getRecordNumber() { |
| return pos; |
| } |
| |
| @Override |
| public int getOffset() { |
| return offsets[pos]; |
| } |
| |
| @Override |
| public RecordType getType() { |
| return RecordType.values()[type[pos]]; |
| } |
| }; |
| } else { |
| return endOfData(); |
| } |
| } |
| }; |
| } |
| |
| } |