MockLedgerHandle.java

/**
 * Copyright 2016 Yahoo Inc.
 *
 * Licensed 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.client;

import java.security.GeneralSecurityException;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.Queue;
import java.util.concurrent.RejectedExecutionException;

import org.apache.bookkeeper.client.AsyncCallback.AddCallback;
import org.apache.bookkeeper.client.AsyncCallback.CloseCallback;
import org.apache.bookkeeper.client.AsyncCallback.ReadCallback;
import org.apache.bookkeeper.client.BookKeeper.DigestType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.Lists;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;

public class MockLedgerHandle extends LedgerHandle {

    final ArrayList<LedgerEntry> entries = Lists.newArrayList();
    final MockBookKeeper bk;
    final long id;
    final DigestType digest;
    final byte[] passwd;
    long lastEntry = -1;
    boolean fenced = false;

    MockLedgerHandle(MockBookKeeper bk, long id, DigestType digest, byte[] passwd) throws GeneralSecurityException {
        super(bk, id, new LedgerMetadata(3, 3, 2, DigestType.MAC, "".getBytes()), DigestType.MAC, "".getBytes());
        this.bk = bk;
        this.id = id;
        this.digest = digest;
        this.passwd = Arrays.copyOf(passwd, passwd.length);
    }

    @Override
    public void asyncClose(CloseCallback cb, Object ctx) {
        if (bk.getProgrammedFailStatus()) {
            cb.closeComplete(bk.failReturnCode, this, ctx);
            return;
        }

        fenced = true;
        try {
            bk.executor.execute(() -> cb.closeComplete(0, this, ctx));    
        } catch (RejectedExecutionException e) {
            cb.closeComplete(0, this, ctx);
        }
        
    }

    @Override
    public void asyncReadEntries(final long firstEntry, final long lastEntry, final ReadCallback cb, final Object ctx) {
        if (bk.isStopped()) {
            cb.readComplete(-1, MockLedgerHandle.this, null, ctx);
            return;
        }

        bk.executor.execute(new Runnable() {
            public void run() {
                if (bk.getProgrammedFailStatus()) {
                    cb.readComplete(bk.failReturnCode, MockLedgerHandle.this, null, ctx);
                    return;
                } else if (bk.isStopped()) {
                    log.debug("Bookkeeper is closed!");
                    cb.readComplete(-1, MockLedgerHandle.this, null, ctx);
                    return;
                }

                log.debug("readEntries: first={} last={} total={}", firstEntry, lastEntry, entries.size());
                final Queue<LedgerEntry> seq = new ArrayDeque<LedgerEntry>();
                long entryId = firstEntry;
                while (entryId <= lastEntry && entryId < entries.size()) {
                    seq.add(entries.get((int) entryId++));
                }

                log.debug("Entries read: {}", seq);

                try {
                    Thread.sleep(1);
                } catch (InterruptedException e) {
                }

                cb.readComplete(0, MockLedgerHandle.this, new Enumeration<LedgerEntry>() {
                    public boolean hasMoreElements() {
                        return !seq.isEmpty();
                    }

                    public LedgerEntry nextElement() {
                        return seq.remove();
                    }

                }, ctx);
            }
        });
    }

    @Override
    public void asyncReadLastEntry(final ReadCallback cb, final Object ctx) {
        long lastEntryId = getLastAddConfirmed();
        asyncReadEntries(lastEntryId, lastEntryId, cb, ctx);
    }

    @Override
    public long addEntry(byte[] data) throws InterruptedException, BKException {
        try {
            bk.checkProgrammedFail();
        } catch (BKException e) {
            fenced = true;
            throw e;
        }

        if (fenced) {
            throw BKException.create(BKException.Code.LedgerFencedException);
        }

        if (bk.isStopped()) {
            throw BKException.create(BKException.Code.NoBookieAvailableException);
        }

        lastEntry = entries.size();
        entries.add(new MockLedgerEntry(ledgerId, lastEntry, data));
        return lastEntry;
    }

    @Override
    public void asyncAddEntry(final byte[] data, final AddCallback cb, final Object ctx) {
        asyncAddEntry(data, 0, data.length, cb, ctx);
    }

    @Override
    public void asyncAddEntry(final byte[] data, final int offset, final int length, final AddCallback cb,
            final Object ctx) {
        asyncAddEntry(Unpooled.wrappedBuffer(data, offset, length), cb, ctx);
    }

    @Override
    public void asyncAddEntry(final ByteBuf data, final AddCallback cb, final Object ctx) {
        if (bk.isStopped()) {
            cb.addComplete(-1, MockLedgerHandle.this, INVALID_ENTRY_ID, ctx);
            return;
        }

        data.retain();
        bk.executor.execute(new Runnable() {
            public void run() {
                if (bk.getProgrammedFailStatus()) {
                    fenced = true;
                    data.release();
                    cb.addComplete(bk.failReturnCode, MockLedgerHandle.this, INVALID_ENTRY_ID, ctx);
                    return;
                }
                if (bk.isStopped()) {
                    data.release();
                    cb.addComplete(-1, MockLedgerHandle.this, INVALID_ENTRY_ID, ctx);
                    return;
                }

                try {
                    Thread.sleep(1);
                } catch (InterruptedException e) {
                }

                if (fenced) {
                    data.release();
                    cb.addComplete(BKException.Code.LedgerFencedException, MockLedgerHandle.this,
                            LedgerHandle.INVALID_ENTRY_ID, ctx);
                } else {
                    lastEntry = entries.size();
                    byte[] storedData = new byte[data.readableBytes()];
                    data.readBytes(storedData);
                    LedgerEntry entry = new MockLedgerEntry(ledgerId, lastEntry, storedData);
                    entries.add(entry);
                    data.release();
                    cb.addComplete(0, MockLedgerHandle.this, lastEntry, ctx);
                }
            }
        });
    }

    @Override
    public long getId() {
        return ledgerId;
    }

    @Override
    public long getLastAddConfirmed() {
        return lastEntry;
    }

    @Override
    public long getLength() {
        long length = 0;
        for (LedgerEntry entry : entries) {
            length += entry.getLength();
        }

        return length;
    }

    private static final Logger log = LoggerFactory.getLogger(MockLedgerHandle.class);

}