/*
* 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 Software Foundation, 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.index.SqlIndexAlreadyExistsException;
import com.caucho.db.index.StringKeyCompare;
import com.caucho.db.sql.Expr;
import com.caucho.db.sql.QueryContext;
import com.caucho.db.sql.SelectResult;
import com.caucho.db.xa.DbTransaction;
import com.caucho.util.L10N;
class StringColumn extends Column {
private static final L10N L = new L10N(StringColumn.class);
private final int _maxLength;
/**
* Creates a string column.
*
* @param columnOffset the offset within the row
* @param maxLength the maximum length of the string
*/
StringColumn(Row row, String name, int maxLength)
{
super(row, name);
if (maxLength < 0)
throw new IllegalArgumentException("length must be non-negative");
else if (255 < maxLength)
throw new IllegalArgumentException("length too big");
_maxLength = maxLength;
}
/**
* Returns the type code for the column.
*/
@Override
public ColumnType getTypeCode()
{
return ColumnType.VARCHAR;
}
/**
* Returns the java type.
*/
@Override
public Class<?> getJavaType()
{
return String.class;
}
/**
* Returns the declaration size
*/
@Override
public int getDeclarationSize()
{
return _maxLength;
}
/**
* Returns the column's size.
*/
@Override
public int getLength()
{
return 2 * _maxLength + 1;
}
/**
* Returns the key compare for the column.
*/
@Override
public KeyCompare getIndexKeyCompare()
{
return new StringKeyCompare();
}
/**
* Sets the string value.
*
* @param block the buffer to store the row
* @param rowOffset the offset into the row
* @param str the string value
*/
@Override
void setString(DbTransaction xa, byte []block, int rowOffset, String str)
{
int offset = rowOffset + _columnOffset;
if (str == null) {
setNull(block, rowOffset);
return;
}
int len = str.length();
int maxOffset = offset + 2 * _maxLength + 1;
block[offset++] = (byte) (len);
for (int i = 0; i < len && offset < maxOffset; i++) {
int ch = str.charAt(i);
block[offset++] = (byte) (ch >> 8);
block[offset++] = (byte) (ch);
}
setNonNull(block, rowOffset);
}
@Override
public String getString(long blockId, byte []block, int rowOffset)
{
if (isNull(block, rowOffset))
return null;
int startOffset = rowOffset + _columnOffset;
int len = block[startOffset] & 0xff;
char []cBuf = new char[len];
int offset = startOffset + 1;
int endOffset = offset + 2 * len;
int i = 0;
while (offset < endOffset) {
int ch1 = block[offset++] & 0xff;
int ch2 = block[offset++] & 0xff;
cBuf[i++] = (char) ((ch1 << 8) + ch2);
}
return new String(cBuf, 0, cBuf.length);
}
/**
* 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
setString(xa, block, rowOffset, expr.evalString(context));
}
/**
* 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 len1 = block1[startOffset1] & 0xff;
int startOffset2 = rowOffset2 + _columnOffset;
int len2 = block2[startOffset2] & 0xff;
if (len1 != len2)
return false;
for (int i = 2 * len1; i > 0; i--) {
if (block1[startOffset1 + i] != block2[startOffset2 + i])
return false;
}
return true;
}
/**
* Returns true if the bytes match.
*/
@Override
public boolean isEqual(byte []block, int rowOffset,
byte []buffer, int offset, int length)
{
if (isNull(block, rowOffset))
return false;
int startOffset = rowOffset + _columnOffset;
int len = block[startOffset] & 0xff;
if (len != length)
return false;
int blockOffset = startOffset + 1;
int endOffset = blockOffset + 2 * len;
while (blockOffset < endOffset) {
if (block[blockOffset++] != buffer[offset++])
return false;
}
return true;
}
@Override
public boolean isEqual(long blockId,
byte []block, int rowOffset, String value)
{
if (value == null)
return isNull(block, rowOffset);
else if (isNull(block, rowOffset))
return false;
int startOffset = rowOffset + _columnOffset;
int len = block[startOffset] & 0xff;
int strLength = value.length();
int strOffset = 0;
int offset = startOffset + 1;
int endOffset = offset + 2 * len;
while (offset < endOffset && strOffset < strLength) {
int ch1 = ((block[offset++] & 0xff) << 8) + (block[offset++] & 0xff);
char ch = value.charAt(strOffset++);
if (ch1 != ch)
return false;
}
return offset == endOffset && strOffset == strLength;
}
/**
* 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;
int len = block[startOffset] & 0xff;
result.writeString(block, startOffset + 1, len);
/*
result.write(Column.VARCHAR);
result.write(0);
result.write(0);
result.write(0);
result.write(len);
result.write(block, startOffset + 1, len);
*/
}
/**
* 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;
// static length for now
int len = getLength();
System.arraycopy(block, startOffset, buffer, bufferOffset, len);
return len;
}
/**
* 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) {
try {
index.insert(block,
rowOffset + _columnOffset, getLength(),
rowAddr,
false);
} catch (SqlIndexAlreadyExistsException e) {
long blockId = 0;
throw new SqlIndexAlreadyExistsException(L.l("StringColumn '{0}.{1}' unique index set failed for {2}.\n{3}",
getTable().getName(),
getName(),
getString(blockId, block, rowOffset),
e.toString()),
e);
}
}
}
/**
* 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, getLength());
}
public String toString()
{
if (getIndex() != null)
return getClass().getSimpleName() + "[" + getName() + ",index]";
else
return getClass().getSimpleName() + "[" + getName() + "]";
}
}