swamirishi commented on code in PR #5619: URL: https://github.com/apache/ozone/pull/5619#discussion_r1399628457
########## hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/ListIterator.java: ########## @@ -0,0 +1,355 @@ +/* + * 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 + * <p> + * http://www.apache.org/licenses/LICENSE-2.0 + * <p> + * 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.hadoop.ozone.om; + +import org.apache.commons.lang3.StringUtils; +import org.apache.hadoop.hdds.utils.db.CopyObject; +import org.apache.hadoop.hdds.utils.db.Table; +import org.apache.hadoop.hdds.utils.db.TableIterator; +import org.apache.hadoop.hdds.utils.db.cache.CacheKey; +import org.apache.hadoop.hdds.utils.db.cache.CacheValue; +import org.apache.hadoop.ozone.om.helpers.BucketLayout; + +import java.io.Closeable; +import java.io.IOException; +import java.util.ArrayList; +import java.util.Comparator; +import java.util.Iterator; +import java.util.Map; +import java.util.NoSuchElementException; +import java.util.PriorityQueue; +import java.util.TreeMap; + +import static org.apache.hadoop.ozone.om.lock.OzoneManagerLock.Resource.BUCKET_LOCK; + +/** + * Common class to do listing of resources after merging + * rocksDB table cache & actual table. + */ +public class ListIterator { + + /** + * Interface for iteration of Heap Entries. + */ + public interface ClosableIterator extends Iterator<HeapEntry>, Closeable { + + } + + /** + * Entry to be added to the heap. + */ + public static class HeapEntry implements Comparable<HeapEntry> { + private final int entryInteratorId; + private final String tableName; + private final String key; + private final Object value; + + HeapEntry(int entryInteratorId, String tableName, String key, + Object value) { + this.entryInteratorId = entryInteratorId; + this.tableName = tableName; + this.key = key; + this.value = value; + } + + public String getKey() { + return this.key; + } + + private int getEntryInteratorId() { + return this.entryInteratorId; + } + + public String getTableName() { + return tableName; + } + + public Object getValue() { + return value; + } + + public int compareTo(HeapEntry other) { + return Comparator.comparing(HeapEntry::getKey) + .thenComparing(HeapEntry::getEntryInteratorId).compare(this, other); + } + + public boolean equals(Object other) { + if (other == null) { + return false; + } + + if (!(other instanceof HeapEntry)) { + return false; + } + + + HeapEntry that = (HeapEntry) other; + return this.compareTo(that) == 0; + } + + public int hashCode() { + return key.hashCode(); + } + } + + /** + * Iterator for DB entries in a Dir and File Table. + */ + public static class RawIter<Value> implements + ClosableIterator { + private final int entryInteratorId; + private final String prefixKey; + private final TableIterator<String, + ? extends Table.KeyValue<String, Value>> tableIterator; + + private final Table<String, Value> table; + private HeapEntry currentKey; + + RawIter(int entryInteratorId, Table<String, Value> table, + String prefixKey, String startKey) throws IOException { + this.entryInteratorId = entryInteratorId; + this.table = table; + this.tableIterator = table.iterator(prefixKey); + this.prefixKey = prefixKey; + this.currentKey = null; + + // only seek for the start key if the start key is lexicographically + // after the prefix key. For example + // Prefix key = 1024/c, Start key = 1024/a + // then do not seek for the start key + // + // on the other hand, + // Prefix key = 1024/a, Start key = 1024/c + // then seek for the start key + if (!StringUtils.isBlank(startKey) && + startKey.compareTo(prefixKey) > 0) { + tableIterator.seek(startKey); + } + + getNextKey(); + } + + private void getNextKey() throws IOException { + while (tableIterator.hasNext() && currentKey == null) { + Table.KeyValue<String, Value> entry = tableIterator.next(); + String entryKey = entry.getKey(); + if (entryKey.startsWith(prefixKey)) { + if (!KeyManagerImpl.isKeyDeleted(entryKey, table)) { + currentKey = new HeapEntry(entryInteratorId, + table.getName(), entryKey, entry.getValue()); + } + } else { + // if the prefix key does not match, then break + // as the iterator is beyond the prefix. + break; + } + } + } + + public boolean hasNext() { + try { + getNextKey(); + } catch (Throwable t) { + throw new NoSuchElementException(); + } + return currentKey != null; + } + + public HeapEntry next() { + try { + getNextKey(); + } catch (Throwable t) { + throw new NoSuchElementException(); + } + HeapEntry ret = currentKey; + currentKey = null; + + return ret; Review Comment: I guess this should be fine. handling runtime exception would require us to change other part of the code. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
