/**
* Copyright (C) 2009-2013 FoundationDB, LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.foundationdb.server.rowdata;
import com.foundationdb.ais.model.AkibanInformationSchema;
import com.foundationdb.ais.model.Table;
import com.foundationdb.server.AkServerUtil;
import com.foundationdb.server.rowdata.encoding.EncodingException;
import com.foundationdb.util.AkibanAppender;
/**
* Represent one or more rows of table data. The backing store is a byte array
* supplied in the constructor. The {@link #RowData(byte[], int, int)}
* constructor allows use of a partially filled reusable buffer.
*
* This class provides methods for both interpreting and constructing row data
* structures in the byte array. After a call to {@link #reset(int, int)} the
* index will point to the first field of the first row represented in the
* buffer.
*
* <pre>
* +0: record length (Z)
* +4: signature bytes, e.g., 'AB'
* +6: field count (short)
* +8: rowDefId (int)
* +12: null-map (1 bit per schema-defined column)
* +M: fixed-length field
* +N: fixed-length field ...
* +Q: variable-length field
* +R: variable-length field ...
* +Z-6: signature bytes: e.g., 'BA'
* +Z-4: record length (Z)
* </pre>
*
* @author peter
*/
public class RowData {
public final static int O_LENGTH_A = 0;
public final static int O_SIGNATURE_A = 4;
public final static int O_FIELD_COUNT = 6;
public final static int O_ROW_DEF_ID = 8;
public final static int O_NULL_MAP = 12;
public final static int O_SIGNATURE_B = -6;
public final static int O_LENGTH_B = -4;
public final static int MINIMUM_RECORD_LENGTH = 18;
// Arbitrary sanity bound on maximum size
public final static int MAXIMUM_RECORD_LENGTH = 8 * 1024 * 1024;
public final static char SIGNATURE_A = (char) ('A' + ('B' << 8));
public final static char SIGNATURE_B = (char) ('B' + ('A' << 8));
public final static int ENVELOPE_SIZE = 12;
public final static int LEFT_ENVELOPE_SIZE = 6;
public final static int RIGHT_ENVELOPE_SIZE = 6;
public final static int CREATE_ROW_INITIAL_SIZE = 500;
private byte[] bytes;
private int bufferStart;
private int bufferEnd;
private int rowStart;
private int rowEnd;
public RowData() {
}
public RowData(final byte[] bytes) {
this.bytes = bytes;
reset(0, bytes.length);
}
public RowData(final byte[] bytes, final int offset, final int length) {
this.bytes = bytes;
reset(offset, length);
}
public void reset(final int offset, final int length) {
this.bufferStart = offset;
this.bufferEnd = offset + length;
rowStart = rowEnd = bufferStart;
}
public void reset(final byte[] bytes) {
this.bytes = bytes;
reset(0, bytes.length);
}
public void reset(final byte[] bytes, final int offset, final int length) {
this.bytes = bytes;
reset(offset, length);
}
/**
* Interpret the length and signature fixed fields of the row at the
* specified offset. This method sets the {@link #rowStart} and {@link #rowEnd}
* fields so that subsequent calls to interpret fields are supported.
*
* @param offset
* byte offset to record start within the buffer
*/
public boolean prepareRow(final int offset) throws CorruptRowDataException {
if (offset == bufferEnd) {
return false;
}
if (offset < 0 || offset + MINIMUM_RECORD_LENGTH > bufferEnd) {
throw new CorruptRowDataException("Invalid offset: " + offset);
} else {
validateRow(offset);
rowStart = offset;
rowEnd = offset + AkServerUtil.getInt(bytes, O_LENGTH_A + offset);
return true;
}
}
public void validateRow(final int offset) throws CorruptRowDataException {
if (offset < 0 || offset + MINIMUM_RECORD_LENGTH > bufferEnd) {
throw new CorruptRowDataException("Invalid offset: " + offset);
} else {
final int recordLength = AkServerUtil.getInt(bytes, O_LENGTH_A + offset);
if (recordLength < 0 || recordLength + offset > bufferEnd) {
throw new CorruptRowDataException("Invalid record length: "
+ recordLength + " at offset: " + offset);
}
if (AkServerUtil.getUShort(bytes, O_SIGNATURE_A + offset) != SIGNATURE_A) {
throw new CorruptRowDataException(
"Invalid signature at offset: " + offset);
}
final int trailingLength = AkServerUtil.getInt(bytes, offset + recordLength + O_LENGTH_B);
if (trailingLength != recordLength) {
throw new CorruptRowDataException(
"Invalid trailing record length " + trailingLength
+ " in record at offset: " + offset);
}
if (AkServerUtil.getUShort(bytes, offset + recordLength + O_SIGNATURE_B) != SIGNATURE_B) {
throw new CorruptRowDataException(
"Invalid signature at offset: " + offset);
}
}
}
public int getBufferStart() {
return bufferStart;
}
public int getBufferLength() {
return bufferEnd - bufferStart;
}
public int getBufferEnd() {
return bufferEnd;
}
public int getRowStart() {
return rowStart;
}
public int getRowStartData() {
return rowStart + O_NULL_MAP + (getFieldCount() + 7) / 8;
}
public int getRowEnd() {
return rowEnd;
}
public int getRowSize() {
return rowEnd - rowStart;
}
public int getInnerStart() {
return rowStart + O_FIELD_COUNT;
}
public int getInnerSize() {
return rowEnd - rowStart + O_SIGNATURE_B - O_FIELD_COUNT;
}
public int getFieldCount() {
return AkServerUtil.getUShort(bytes, rowStart + O_FIELD_COUNT);
}
public int getRowDefId() {
return AkServerUtil.getInt(bytes, rowStart + O_ROW_DEF_ID);
}
public byte[] getBytes() {
return bytes;
}
public int getColumnMapByte(final int offset) {
return bytes[offset + rowStart + O_NULL_MAP] & 0xFF;
}
public boolean isNull(final int fieldIndex) {
if (fieldIndex < 0 || fieldIndex >= getFieldCount()) {
throw new IllegalArgumentException("No such field " + fieldIndex
+ " in " + this);
} else {
return (getColumnMapByte(fieldIndex / 8) & (1 << (fieldIndex % 8))) != 0;
}
}
public long getIntegerValue(final int offset, final int width) {
checkOffsetAndWidth(offset, width);
return AkServerUtil.getSignedIntegerByWidth(bytes, offset, width);
}
public long getUnsignedIntegerValue(final int offset, final int width) {
checkOffsetAndWidth(offset, width);
return AkServerUtil.getUnsignedIntegerByWidth(bytes, offset, width);
}
public String getStringValue(final int offset, final int width, final FieldDef fieldDef) {
if (offset == 0 && width == 0) {
return null;
}
checkOffsetAndWidth(offset, width);
return AkServerUtil.decodeMySQLString(bytes, offset, width, fieldDef);
}
private void checkOffsetAndWidth(int offset, int width) {
if (offset < rowStart || offset + width >= rowEnd) {
throw new IllegalArgumentException(String.format("Bad location: {offset=%d width=%d start=%d end=%d}",
offset, width, rowStart, rowEnd));
}
}
public RowData copy()
{
byte[] copyBytes = new byte[rowEnd - rowStart];
System.arraycopy(bytes, rowStart, copyBytes, 0, rowEnd - rowStart);
RowData copy = new RowData(copyBytes);
copy.prepareRow(0);
return copy;
}
public void createRow(final RowDef rowDef, final Object[] values, boolean growBuffer)
{
if (growBuffer && !(bufferStart == 0 && bufferEnd == bytes.length)) {
// This RowData is embedded in a larger buffer. Can't grow it safely.
throw new CannotGrowBufferException();
}
RuntimeException exception = null;
do {
try {
exception = null;
createRow(rowDef, values);
} catch (ArrayIndexOutOfBoundsException e) {
exception = e;
} catch (EncodingException e) {
if (e.getCause() instanceof ArrayIndexOutOfBoundsException) {
exception = e;
} else {
throw e;
}
}
if (exception != null && growBuffer) {
int newSize = bytes.length == 0 ? CREATE_ROW_INITIAL_SIZE : bytes.length * 2;
reset(new byte[newSize]);
}
} while (growBuffer && exception != null);
if (exception != null) {
throw exception;
}
}
public void createRow(final RowDef rowDef, final Object[] values)
{
if (values.length > rowDef.getFieldCount()) {
throw new IllegalArgumentException("Too many values.");
}
RowDataBuilder builder = new RowDataBuilder(rowDef, this);
builder.startAllocations();
for (int i=0; i < values.length; ++i) {
FieldDef fieldDef = rowDef.getFieldDef(i);
builder.allocate(fieldDef, values[i]);
}
builder.startPuts();
for (Object object : values) {
builder.putObject(object);
}
rowEnd = builder.finalOffset();
}
public void updateNonNullLong(FieldDef fieldDef, long rowId)
{
// Offset is in low 32 bits of fieldLocation return value
int offset = (int) fieldDef.getRowDef().fieldLocation(this, fieldDef.getFieldIndex());
AkServerUtil.putLong(bytes, offset, rowId);
}
@Override
public String toString() {
return toString(RowDefBuilder.LATEST_FOR_DEBUGGING);
}
public String toString(AkibanInformationSchema ais) {
if (ais == null) {
return toStringWithoutRowDef("No AIS");
}
int rowDefID = getRowDefId();
Table table = ais.getTable(rowDefID);
if(table == null) {
return toStringWithoutRowDef("Unknown RowDefID(" + rowDefID + ")");
}
return toString(table.rowDef());
}
public String toString(final RowDef rowDef)
{
if (rowDef == null) {
return toStringWithoutRowDef("No RowDef provided");
}
final AkibanAppender sb = AkibanAppender.of(new StringBuilder());
RowDataValueSource source = new RowDataValueSource();
try {
sb.append(rowDef.table().getName().getTableName());
for (int i = 0; i < getFieldCount(); i++) {
final FieldDef fieldDef = rowDef.getFieldDef(i);
sb.append(i == 0 ? '(' : ',');
final long location = fieldDef.getRowDef().fieldLocation(
this, fieldDef.getFieldIndex());
if (location == 0) {
// sb.append("null");
} else {
source.bind(fieldDef, this);
fieldDef.column().getType().format(source, sb);
}
}
sb.append(')');
} catch (Exception e) {
int size = Math.min(getRowSize(), 64);
if (size > 0 && rowStart >= 0) {
sb.append(AkServerUtil.dump(bytes, rowStart, size));
}
return sb.toString();
}
return sb.toString();
}
/** Returns a hex-dump of the backing buffer. */
public String toStringWithoutRowDef(String missingRowDefExplanation) {
final AkibanAppender sb = AkibanAppender.of(new StringBuilder());
try {
sb.append("RowData[");
sb.append(missingRowDefExplanation);
sb.append("]?(rowDefId=");
sb.append(getRowDefId());
sb.append(": ");
AkServerUtil.hex(sb, bytes, rowStart, rowEnd - rowStart);
} catch (Exception e) {
int size = Math.min(getRowSize(), 64);
if (size > 0 && rowStart >= 0) {
sb.append(AkServerUtil.dump(bytes, rowStart, size));
}
return sb.toString();
}
return sb.toString();
}
}