/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source 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, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.db.table;
import java.sql.SQLException;
import com.caucho.db.index.BTree;
import com.caucho.db.index.KeyCompare;
import com.caucho.db.sql.Expr;
import com.caucho.db.sql.QueryContext;
import com.caucho.db.sql.SelectResult;
import com.caucho.db.xa.DbTransaction;
/**
* Represents a 16-bit integer column.
*/
class ShortColumn extends Column {
/**
* Creates a 16-bit integer column.
*
* @param columnOffset the offset within the row
* @param maxLength the maximum length of the string
*/
ShortColumn(Row row, String name)
{
super(row, name);
}
/**
* Returns the column's type code.
*/
@Override
public ColumnType getTypeCode()
{
return ColumnType.SHORT;
}
/**
* Returns the column's Java type.
*/
@Override
public Class<?> getJavaType()
{
return short.class;
}
/**
* Returns the column's declaration size.
*/
@Override
public int getDeclarationSize()
{
return 2;
}
/**
* Returns the column's size.
*/
@Override
public int getLength()
{
return 2;
}
/**
* Returns the key compare for the column.
*/
@Override
public KeyCompare getIndexKeyCompare()
{
return null;
}
/**
* Returns a String value from the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
*/
@Override
public String getString(long blockId, byte []block, int rowOffset)
{
if (isNull(block, rowOffset))
return null;
else
return String.valueOf(getInteger(blockId, block, rowOffset));
}
/**
* Sets a string value in the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
* @param value the value to store
*/
@Override
void setString(DbTransaction xa, byte []block, int rowOffset, String str)
{
if (str == null)
setNull(block, rowOffset);
else
setInteger(xa, block, rowOffset, (int) Long.parseLong(str));
}
/**
* Returns a int value from the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
*/
@Override
public int getInteger(long blockId, byte []block, int rowOffset)
{
if (isNull(block, rowOffset))
return 0;
int offset = rowOffset + _columnOffset;
int value = 0;
value = (block[offset++] & 0xff) << 8;
value |= (block[offset++] & 0xff);
return (short) value;
}
/**
* Sets an integer value in the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
* @param value the value to store
*/
@Override
void setInteger(DbTransaction xa, byte []block, int rowOffset, int value)
{
int offset = rowOffset + _columnOffset;
block[offset++] = (byte) (value >> 8);
block[offset++] = (byte) (value);
setNonNull(block, rowOffset);
}
/**
* Sets a long value in the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
* @param value the value to store
*/
@Override
void setLong(DbTransaction xa, byte []block, int rowOffset, long value)
{
setInteger(xa, block, rowOffset, (int) value);
}
/**
* Returns a long value from the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
*/
@Override
public long getLong(long blockId, byte []block, int rowOffset)
{
return getInteger(blockId, block, rowOffset);
}
/**
* Sets the column based on an expression.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
* @param expr the expression to store
*/
@Override
void setExpr(DbTransaction xa,
byte []block, int rowOffset,
Expr expr, QueryContext context)
throws SQLException
{
if (expr.isNull(context))
setNull(block, rowOffset);
else
setInteger(xa, block, rowOffset, (int) expr.evalLong(context));
}
/**
* Evaluates the column to a stream.
*/
@Override
public void evalToResult(long blockId, byte []block, int rowOffset,
SelectResult result)
{
if (isNull(block, rowOffset)) {
result.writeNull();
return;
}
int startOffset = rowOffset + _columnOffset;
result.write(ColumnType.SHORT.ordinal());
result.write(block, startOffset, 2);
}
/**
* Evaluate to a buffer.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
* @param buffer the result buffer
* @param buffer the result buffer offset
*
* @return the length of the value
*/
@Override
int evalToBuffer(byte []block, int rowOffset,
byte []buffer, int bufferOffset)
throws SQLException
{
if (isNull(block, rowOffset))
return 0;
int startOffset = rowOffset + _columnOffset;
int len = 2;
System.arraycopy(block, startOffset, buffer, bufferOffset, len);
return len;
}
/**
* Returns true if the items in the given rows match.
*/
@Override
public boolean isEqual(byte []block1, int rowOffset1,
byte []block2, int rowOffset2)
{
if (isNull(block1, rowOffset1) != isNull(block2, rowOffset2))
return false;
int startOffset1 = rowOffset1 + _columnOffset;
int startOffset2 = rowOffset2 + _columnOffset;
return (block1[startOffset1 + 0] == block2[startOffset2 + 0]
&& block1[startOffset1 + 1] == block2[startOffset2 + 1]);
}
/**
* Sets any index for the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
* @param rowAddr the address of the row
*/
@Override
void setIndex(DbTransaction xa,
byte []block, int rowOffset,
long rowAddr, QueryContext context)
throws SQLException
{
BTree index = getIndex();
if (index == null)
return;
index.insert(block, rowOffset + _columnOffset, 2, rowAddr, false);
}
/**
* Sets based on an iterator.
*/
public void set(TableIterator iter, Expr expr, QueryContext context)
throws SQLException
{
iter.setDirty();
setInteger(iter.getTransaction(),
iter.getBuffer(), iter.getRowOffset(),
(int) expr.evalLong(context));
}
/**
* Deleting the row, based on the column.
*
* @param block the block's buffer
* @param rowOffset the offset of the row in the block
* @param expr the expression to store
*/
@Override
void deleteIndex(DbTransaction xa, byte []block, int rowOffset)
throws SQLException
{
BTree index = getIndex();
if (index != null)
index.remove(block, rowOffset + _columnOffset, 2);
}
}