| /* |
| * 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.iotdb.db.schemaengine.schemaregion.mtree.impl.pbtree.schemafile; |
| |
| import org.apache.iotdb.commons.exception.MetadataException; |
| import org.apache.iotdb.commons.utils.TestOnly; |
| import org.apache.iotdb.db.exception.metadata.schemafile.SegmentNotFoundException; |
| import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils; |
| |
| import java.io.IOException; |
| import java.io.OutputStream; |
| import java.nio.ByteBuffer; |
| import java.nio.channels.FileChannel; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import java.util.concurrent.locks.ReadWriteLock; |
| import java.util.concurrent.locks.ReentrantReadWriteLock; |
| |
| public interface ISchemaPage { |
| /** |
| * <b>Page Header Structure: (23 bytes used, 9 bytes reserved)</b> |
| * |
| * <ul> |
| * <li>1 byte: page type indicator |
| * <li>1 int (4 bytes): pageIndex, a non-negative number |
| * <li>1 short (2 bytes): spareOffset, bound of the variable length part in a slotted structure |
| * <li>1 short (2 bytes): spareSize, space left to use |
| * <li>1 short (2 bytes): memberNum, amount of the member whose type depends on implementation |
| * <li>1 long (8 bytes): firstLeaf, points to first segmented page, only in {@link InternalPage} |
| * <li>1 int (4 bytes): subIndexPage, points to sub-index, only in {@link InternalPage} |
| * </ul> |
| * |
| * <p>While header of a page is partly fixed, the body is dependent on implementation. |
| */ |
| static SchemaPage loadSchemaPage(ByteBuffer buffer) throws MetadataException { |
| buffer.clear(); |
| byte pageType = ReadWriteIOUtils.readByte(buffer); |
| |
| switch (pageType) { |
| case SchemaFileConfig.SEGMENTED_PAGE: |
| return new SegmentedPage(buffer); |
| case SchemaFileConfig.INTERNAL_PAGE: |
| return new InternalPage(buffer); |
| case SchemaFileConfig.ALIAS_PAGE: |
| return new AliasIndexPage(buffer); |
| default: |
| throw new MetadataException( |
| "ByteBuffer is corrupted or set to a wrong position to load as a SchemaPage."); |
| } |
| } |
| |
| /** InternalPage should be initiated with a pointer which points to the minimal child of it. */ |
| static SchemaPage initInternalPage( |
| ByteBuffer buffer, int pageIndex, int ptr, AtomicInteger ai, ReadWriteLock rwl) { |
| buffer.clear(); |
| |
| buffer.position(SchemaFileConfig.PAGE_HEADER_SIZE); |
| ReadWriteIOUtils.write( |
| ((SchemaFileConfig.PAGE_INDEX_MASK & ptr) << SchemaFileConfig.COMP_POINTER_OFFSET_DIGIT), |
| buffer); |
| |
| buffer.position(0); |
| ReadWriteIOUtils.write(SchemaFileConfig.INTERNAL_PAGE, buffer); |
| ReadWriteIOUtils.write(pageIndex, buffer); |
| ReadWriteIOUtils.write((short) buffer.capacity(), buffer); |
| ReadWriteIOUtils.write( |
| (short) |
| (buffer.capacity() |
| - SchemaFileConfig.PAGE_HEADER_SIZE |
| - InternalPage.COMPOUND_POINT_LENGTH), |
| buffer); |
| ReadWriteIOUtils.write((short) 1, buffer); |
| ReadWriteIOUtils.write(-1L, buffer); |
| ReadWriteIOUtils.write(-1, buffer); |
| |
| return new InternalPage(buffer, ai, rwl); |
| } |
| |
| static SchemaPage initInternalPage(ByteBuffer buffer, int pageIndex, int ptr) { |
| return initInternalPage( |
| buffer, pageIndex, ptr, new AtomicInteger(), new ReentrantReadWriteLock()); |
| } |
| |
| static ISegmentedPage initSegmentedPage( |
| ByteBuffer buffer, int pageIndex, AtomicInteger ai, ReadWriteLock rwl) { |
| buffer.clear(); |
| ReadWriteIOUtils.write(SchemaFileConfig.SEGMENTED_PAGE, buffer); |
| ReadWriteIOUtils.write(pageIndex, buffer); |
| ReadWriteIOUtils.write(SchemaFileConfig.PAGE_HEADER_SIZE, buffer); |
| ReadWriteIOUtils.write((short) (buffer.capacity() - SchemaFileConfig.PAGE_HEADER_SIZE), buffer); |
| ReadWriteIOUtils.write((short) 0, buffer); |
| ReadWriteIOUtils.write(-1L, buffer); |
| return new SegmentedPage(buffer, ai, rwl); |
| } |
| |
| static ISegmentedPage initSegmentedPage(ByteBuffer buffer, int pageIndex) { |
| return ISchemaPage.initSegmentedPage( |
| buffer, pageIndex, new AtomicInteger(), new ReentrantReadWriteLock()); |
| } |
| |
| static SchemaPage initAliasIndexPage(ByteBuffer buffer, int pageIndex) { |
| buffer.clear(); |
| ReadWriteIOUtils.write(SchemaFileConfig.ALIAS_PAGE, buffer); |
| ReadWriteIOUtils.write(pageIndex, buffer); |
| ReadWriteIOUtils.write((short) buffer.capacity(), buffer); |
| ReadWriteIOUtils.write((short) (buffer.capacity() - SchemaFileConfig.PAGE_HEADER_SIZE), buffer); |
| ReadWriteIOUtils.write((short) 0, buffer); |
| ReadWriteIOUtils.write(-1L, buffer); |
| return new AliasIndexPage(buffer); |
| } |
| |
| AtomicInteger getRefCnt(); |
| |
| int incrementAndGetRefCnt(); |
| |
| int decrementAndGetRefCnt(); |
| |
| ReadWriteLock getLock(); |
| |
| void syncPageBuffer(); |
| |
| void flushPageToChannel(FileChannel channel) throws IOException; |
| |
| boolean isDirtyPage(); |
| |
| void setDirtyFlag(); |
| |
| void flushPageToStream(OutputStream stream) throws IOException; |
| |
| String inspect() throws SegmentNotFoundException; |
| |
| int getPageIndex(); |
| |
| void setPageIndex(int pid); |
| |
| int getSubIndex(); |
| |
| void setSubIndex(int pid); |
| |
| ISegment<Integer, Integer> getAsInternalPage(); |
| |
| ISegment<String, String> getAsAliasIndexPage(); |
| |
| ISegmentedPage getAsSegmentedPage(); |
| |
| ByteBuffer getEntireSegmentSlice() throws MetadataException; |
| |
| @TestOnly |
| WrappedSegment getSegmentOnTest(short idx) throws SegmentNotFoundException; |
| |
| @TestOnly |
| void getPageBuffer(ByteBuffer dstBuffer); |
| } |