rpuch commented on code in PR #814: URL: https://github.com/apache/ignite-3/pull/814#discussion_r881629261
########## modules/page-memory/src/main/java/org/apache/ignite/internal/pagememory/datapage/ReadPageMemoryRowValue.java: ########## @@ -0,0 +1,141 @@ +/* + * 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.ignite.internal.pagememory.datapage; + +import java.util.Objects; +import org.apache.ignite.internal.pagememory.Storable; +import org.apache.ignite.internal.pagememory.io.DataPagePayload; +import org.apache.ignite.internal.pagememory.util.PageUtils; +import org.jetbrains.annotations.Nullable; + +/** + * Reads full data row value (as byte array) from page memory. Supports fragmented values occupying more than one slot. + * + * <p>This works for the cases when the following conditions are satisfied: + * 1. Row data starts with a fixed-length header, which is followed by the 'value'; the 'value' ends the row data + * 2. Row data header contains 'value' size as an int at a fixed offset known beforehand + * 3. The beginning of the header, including the 'value' size, is always stored in the first slot (i.e. + * {@link Storable#headerSize()} is enough to include 'value' size + */ +public abstract class ReadPageMemoryRowValue implements PageMemoryTraversal<Void> { + /** + * First it's {@code true} (this means that we traverse first slots of versions of the Version Chain using NextLink); + * then it's {@code false} (when we found the version we need and we read its value). + */ + private boolean readingFirstSlot = true; + + private int valueSize; + /** + * Used to collect all the bytes of the target version value. + */ + private byte @Nullable [] allValueBytes; + /** + * Number of bytes written to {@link #allValueBytes}. + */ + private int transferredBytes = 0; + + { + reset(); + } + + @Override + public long consumePagePayload(long link, long pageAddr, DataPagePayload payload, Void ignoredArg) { + if (readingFirstSlot) { + readingFirstSlot = false; + return readFullyOrStartReadingFragmented(pageAddr, payload); + } else { + // we are continuing reading a fragmented row + return readNextFragment(pageAddr, payload); + } + } + + private long readFullyOrStartReadingFragmented(long pageAddr, DataPagePayload payload) { + valueSize = readValueSize(pageAddr, payload); + + if (!payload.hasMoreFragments()) { + return readFully(pageAddr, payload); + } else { + allValueBytes = new byte[valueSize]; + transferredBytes = 0; + + readValueFragmentToArray(pageAddr, payload); Review Comment: Thanks, I fixed this. The tests will be added in https://issues.apache.org/jira/browse/IGNITE-17009 -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
