Issue with Excerpt length

AsynApiRequest.java

import net.openhft.chronicle.ExcerptCommon;

import java.nio.charset.Charset;

public class AsyncAPIRequest implements WALRecord {

    public String tenant;
    public long time;
    public long nanotime;
    public String clazz;
    public String payload;
    public int size;

    public static boolean writeBytes = true;

    public AsyncAPIRequest(String tenant, String clazz, String payload){
        this.tenant = tenant;
        this.time = System.currentTimeMillis();
        this.nanotime = System.nanoTime();
        this.clazz = clazz;
        this.payload = payload;
        this.size = payload.length();
    }

    public AsyncAPIRequest() {
    }

    @Override
    public int getCapacity(){
        int value = 10000 + ((this.payload.length() * 8) * 3);
        if (value > 16000000) {
            return 16000000;
        }
        return value;
    }

    @Override
    public void readMarshallable(ExcerptCommon in) throws IllegalStateException {
        this.tenant = in.readUTF();
        this.time = in.readLong();
        this.nanotime = in.readLong();
        this.clazz = in.readUTF();
        if (writeBytes) {
            this.size = in.readInt();
            byte[] bytes = new byte[size];
            in.read(bytes, 0, size);
            this.payload = new String(bytes, Charset.forName("UTF-8"));
        } else {
          this.payload = in.readUTF();
        }
    }

    @Override
    public void writeMarshallable(ExcerptCommon out) {
        out.writeUTF(tenant);
        out.writeLong(time);
        out.writeLong(nanotime);
        out.writeUTF(clazz);
        if (writeBytes) {
            out.writeInt(size);
            byte[] bytes = payload.getBytes(Charset.forName("UTF-8"));
            out.write(bytes, 0, bytes.length);
        } else {
          out.writeUTF(payload);
        }
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof AsyncAPIRequest)) return false;

        AsyncAPIRequest that = (AsyncAPIRequest) o;

        if (!tenant.equals(that.tenant)) return false;
        if (time != that.time) return false;
        if (nanotime != that.nanotime) return false;
        if (!payload.equals(that.payload)) return false;
        if (!clazz.equals(that.clazz)) return false;

        return true;
    }

    @Override
    public int hashCode() {
        int result = tenant.hashCode();
        result = 31 * result + (int) (time ^ (time >>> 32));
        result = 31 * result + (int) (nanotime ^ (nanotime >>> 32));
        result = 31 * result + clazz.hashCode();
        result = 31 * result + payload.hashCode();
        return result;
    }
}

WalFailWithUTFTest.java

import com.google.common.io.Files;
import AsyncAPIRequest;
import WALRecord;
import WriteAheadLog;
import net.openhft.chronicle.ExcerptTailer;
import org.junit.Test;

import java.io.File;

public class WalFailWithUTFTest {

    @Test
    public void littleMessageWithComputeSize() throws Exception {
        final String payload = "Hello World!!!";
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = true;
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void littleMessageWithComputeSizeAndWriteUTF() throws Exception {
        final String payload = "Hello World!!!";
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = false;
        // This does not fail, because of readUTF/writeUTF and normal payload
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void standardMessageWithComputeSize() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 1; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = true;
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void standardMessageWithComputeSizeAndWriteUTF() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 1; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = false;
        // This does not fail, because of readUTF/writeUTF and normal payload
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void bigMessageWithComputeSize() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 10; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = true;
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void bigMessageWithComputeSizeAndWriteUTF() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 10; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = false;
        // This fail, because of readUTF/writeUTF and big payload ???
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void bigMessageWithComputeSizeAndExtremePayload() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 100; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = true;
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void bigMessageWithComputeSizeAndExtremePayloadAndUTF() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 100; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = false;
        // This fail, because of readUTF/writeUTF and big payload ???
        testWriteReadInWAL(payload, payloadSize);
    }


    @Test
    public void bigMessageWithComputeSizeAndVeryExtremePayload() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 500; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = true;
        testWriteReadInWAL(payload, payloadSize);
    }

    @Test
    public void bigMessageWithComputeSizeAndVeryExtremePayloadAndUTF() throws Exception {
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < 500; i++) {
            builder.append(BLOB);
        }
        final String payload = builder.toString();
        final int payloadSize = payload.length();
        AsyncAPIRequest.writeBytes = false;
        // This fail, because of readUTF/writeUTF and big payload ???
        testWriteReadInWAL(payload, payloadSize);
    }

    public void testWriteReadInWAL(final String payload, final int expectedSize) throws Exception {
        File tmp = Files.createTempDir();
        WriteAheadLog wal = new WriteAheadLog(tmp);
        try {
            final WALRecord record = new AsyncAPIRequest("id", "clazz" , payload);
            wal.append(record); // write in WAL
            wal.redo(new WriteAheadLog.Function() {
                @Override
                public void copyDataToBuffer(long index, ExcerptTailer excerpt) {
                    AsyncAPIRequest read = new AsyncAPIRequest();
                    read.readMarshallable(excerpt); // read from WAL
                    if (expectedSize != read.payload.length()) System.err.println("The payload is truncated from %s characters to actually %s characters", expectedSize, read.payload.length());
                    Assert.assertEquals(expectedSize, read.payload.length());
                    Assert.assertEquals(payload, read.payload);
                }
                @Override
                public void copyDataFromBuffer() {
                    // Nothing to do here
                }
            });
        } finally {
            wal.close();
            tmp.delete();
            tmp.deleteOnExit();
        }
    }

    // length is 10117 characters
    public static final String BLOB = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA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AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";

}

WalRecord.java

public interface WALRecord extends ExcerptMarshallable {
    int getCapacity();
}

WriteAheadLog.java

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import net.openhft.chronicle.ChronicleConfig;
import net.openhft.chronicle.ExcerptAppender;
import net.openhft.chronicle.ExcerptTailer;
import net.openhft.chronicle.IndexedChronicle;

public class WriteAheadLog {

    private String walPath;
    private IndexedChronicle chronicle;
    private ExcerptAppender appender;

    public WriteAheadLog(File directory) {
        this(directory.getAbsolutePath());
    }

    public WriteAheadLog(final String walPath) {
        assert walPath != null;
        try {
            this.initChronicleAndExcerpt(walPath);
        } catch (IOException e) {
            System.err.println("Cannot create Write Ahead Log", e);
        }
    }

    private synchronized void initChronicleAndExcerpt(final String path) throws IOException {
        this.walPath = path;
        this.chronicle = createIndexedChronicle(path);
        this.appender = this.chronicle.createAppender();
    }

    protected static String getWalPathFormat() {
        return new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss-SSS").format(new Date(System.currentTimeMillis()));
    }

    private IndexedChronicle createIndexedChronicle(final String path) throws IOException {
        return new IndexedChronicle(path, ChronicleConfig.SMALL);
    }

    public synchronized void append(final WALRecord walRecord) {
        this.appender.startExcerpt(walRecord.getCapacity());
        walRecord.writeMarshallable(this.appender);
        this.appender.finish();
    }

    public long size() {
        return this.chronicle.size();
    }

    public synchronized void rotate() throws IOException {
        this.rotate(this.getDataFileName().getParent() + "/" + this.getWalPathFormat());
    }

    public synchronized void rotate(final String newPath) throws IOException {
        this.close();
        this.initChronicleAndExcerpt(newPath);
    }

    public synchronized void close() throws IOException {
        this.appender.close();
        this.chronicle.close();
    }

    public File getDataFileName() {
        return new File(this.walPath + ".data");
    }

    public String getPath() {
        return this.walPath;
    }

    public interface Function {
        void copyDataToBuffer(long index, ExcerptTailer excerpt);
        void copyDataFromBuffer();
    }

    public void redo(final Function function) throws IOException {
        this.redo(size(), function);
    }

    public void redo(final long toIndex, final Function function) throws IOException {
        final ExcerptTailer tailer = this.chronicle.createTailer();
        int i = 0;
        while(i < toIndex && tailer.nextIndex()) {
            function.copyDataToBuffer(tailer.index(), tailer);
            tailer.finish();
            i++;
        }
        function.copyDataFromBuffer();
        tailer.close();
        this.close();
    }
}