Java tutorial
/* * 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.bookkeeper.tools.cli.commands.bookie; import com.beust.jcommander.Parameter; import com.google.common.util.concurrent.UncheckedExecutionException; import io.netty.buffer.ByteBufUtil; import io.netty.buffer.UnpooledByteBufAllocator; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.util.concurrent.DefaultThreadFactory; import java.io.IOException; import java.util.Iterator; import java.util.concurrent.CompletableFuture; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.stream.LongStream; import lombok.Setter; import lombok.experimental.Accessors; import org.apache.bookkeeper.client.BKException; import org.apache.bookkeeper.client.BookKeeperAdmin; import org.apache.bookkeeper.client.LedgerEntry; import org.apache.bookkeeper.client.LedgerHandle; import org.apache.bookkeeper.common.util.OrderedExecutor; import org.apache.bookkeeper.conf.ClientConfiguration; import org.apache.bookkeeper.conf.ServerConfiguration; import org.apache.bookkeeper.net.BookieSocketAddress; import org.apache.bookkeeper.proto.BookieClient; import org.apache.bookkeeper.proto.BookieClientImpl; import org.apache.bookkeeper.proto.BookieProtocol; import org.apache.bookkeeper.stats.NullStatsLogger; import org.apache.bookkeeper.tools.cli.helpers.BookieCommand; import org.apache.bookkeeper.tools.framework.CliFlags; import org.apache.bookkeeper.tools.framework.CliSpec; import org.apache.bookkeeper.util.EntryFormatter; import org.apache.bookkeeper.util.LedgerIdFormatter; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Command to read ledger entries. */ public class ReadLedgerCommand extends BookieCommand<ReadLedgerCommand.ReadLedgerFlags> { static final Logger LOG = LoggerFactory.getLogger(ReadLedgerCommand.class); private static final String NAME = "readledger"; private static final String DESC = "Read a range of entries from a ledger."; EntryFormatter entryFormatter; LedgerIdFormatter ledgerIdFormatter; public ReadLedgerCommand() { this(new ReadLedgerFlags()); } public ReadLedgerCommand(EntryFormatter entryFormatter, LedgerIdFormatter ledgerIdFormatter) { this(new ReadLedgerFlags()); this.ledgerIdFormatter = ledgerIdFormatter; this.entryFormatter = entryFormatter; } private ReadLedgerCommand(ReadLedgerFlags flags) { super(CliSpec.<ReadLedgerFlags>newBuilder().withName(NAME).withDescription(DESC).withFlags(flags).build()); } /** * Flags for read ledger command. */ @Accessors(fluent = true) @Setter public static class ReadLedgerFlags extends CliFlags { @Parameter(names = { "-m", "--msg" }, description = "Print message body") private boolean msg; @Parameter(names = { "-l", "--ledgerid" }, description = "Ledger ID") private long ledgerId = -1; @Parameter(names = { "-fe", "--firstentryid" }, description = "First Entry ID") private long firstEntryId = -1; @Parameter(names = { "-le", "--lastentryid" }, description = "Last Entry ID") private long lastEntryId = -1; @Parameter(names = { "-r", "--force-recovery" }, description = "Ensure the ledger is properly closed before reading") private boolean forceRecovery; @Parameter(names = { "-b", "--bookie" }, description = "Only read from a specific bookie") private String bookieAddresss; @Parameter(names = { "-lf", "--ledgeridformatter" }, description = "Set ledger id formatter") private String ledgerIdFormatter; @Parameter(names = { "-ef", "--entryformatter" }, description = "Set entry formatter") private String entryFormatter; } @Override public boolean apply(ServerConfiguration conf, ReadLedgerFlags cmdFlags) { if (cmdFlags.ledgerIdFormatter != null && ledgerIdFormatter == null) { this.ledgerIdFormatter = LedgerIdFormatter.newLedgerIdFormatter(cmdFlags.ledgerIdFormatter, conf); } else if (ledgerIdFormatter == null) { this.ledgerIdFormatter = LedgerIdFormatter.newLedgerIdFormatter(conf); } if (cmdFlags.entryFormatter != null && entryFormatter == null) { this.entryFormatter = EntryFormatter.newEntryFormatter(cmdFlags.entryFormatter, conf); } else if (entryFormatter == null) { this.entryFormatter = EntryFormatter.newEntryFormatter(conf); } try { return readledger(conf, cmdFlags); } catch (Exception e) { throw new UncheckedExecutionException(e.getMessage(), e); } } private boolean readledger(ServerConfiguration serverConf, ReadLedgerFlags flags) throws InterruptedException, BKException, IOException { long lastEntry = flags.lastEntryId; final BookieSocketAddress bookie; if (flags.bookieAddresss != null) { // A particular bookie was specified bookie = new BookieSocketAddress(flags.bookieAddresss); } else { bookie = null; } ClientConfiguration conf = new ClientConfiguration(); conf.addConfiguration(serverConf); try (BookKeeperAdmin bk = new BookKeeperAdmin(conf)) { if (flags.forceRecovery) { // Force the opening of the ledger to trigger recovery try (LedgerHandle lh = bk.openLedger(flags.ledgerId)) { if (lastEntry == -1 || lastEntry > lh.getLastAddConfirmed()) { lastEntry = lh.getLastAddConfirmed(); } } } if (bookie == null) { // No bookie was specified, use normal bk client Iterator<LedgerEntry> entries = bk.readEntries(flags.ledgerId, flags.firstEntryId, lastEntry) .iterator(); while (entries.hasNext()) { LedgerEntry entry = entries.next(); formatEntry(entry, flags.msg); } } else { // Use BookieClient to target a specific bookie EventLoopGroup eventLoopGroup = new NioEventLoopGroup(); OrderedExecutor executor = OrderedExecutor.newBuilder().numThreads(1).name("BookieClientScheduler") .build(); ScheduledExecutorService scheduler = Executors.newSingleThreadScheduledExecutor( new DefaultThreadFactory("BookKeeperClientSchedulerPool")); BookieClient bookieClient = new BookieClientImpl(conf, eventLoopGroup, UnpooledByteBufAllocator.DEFAULT, executor, scheduler, NullStatsLogger.INSTANCE); LongStream.range(flags.firstEntryId, lastEntry).forEach(entryId -> { CompletableFuture<Void> future = new CompletableFuture<>(); bookieClient.readEntry(bookie, flags.ledgerId, entryId, (rc, ledgerId1, entryId1, buffer, ctx) -> { if (rc != BKException.Code.OK) { LOG.error("Failed to read entry {} -- {}", entryId1, BKException.getMessage(rc)); future.completeExceptionally(BKException.create(rc)); return; } System.out .println("--------- Lid=" + ledgerIdFormatter.formatLedgerId(flags.ledgerId) + ", Eid=" + entryId + " ---------"); if (flags.msg) { System.out.println("Data: " + ByteBufUtil.prettyHexDump(buffer)); } future.complete(null); }, null, BookieProtocol.FLAG_NONE); try { future.get(); } catch (Exception e) { LOG.error("Error future.get while reading entries from ledger {}", flags.ledgerId, e); } }); eventLoopGroup.shutdownGracefully(); executor.shutdown(); bookieClient.close(); } } return true; } /** * Format the entry into a readable format. * * @param entry * ledgerentry to print * @param printMsg * Whether printing the message body */ private void formatEntry(LedgerEntry entry, boolean printMsg) { long ledgerId = entry.getLedgerId(); long entryId = entry.getEntryId(); long entrySize = entry.getLength(); System.out.println("--------- Lid=" + ledgerIdFormatter.formatLedgerId(ledgerId) + ", Eid=" + entryId + ", EntrySize=" + entrySize + " ---------"); if (printMsg) { entryFormatter.formatEntry(entry.getEntry()); } } }