/* =============================================================
* SmallSQL : a free Java DBMS library for the Java(tm) platform
* =============================================================
*
* (C) Copyright 2004-2006, by Volker Berlin.
*
* Project Info: http://www.smallsql.de/
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ---------------
* ExpressionFunctionLeft.java
* ---------------
* Author: Volker Berlin
*
* Created on 17.06.2006
*/
package smallsql.database;
/**
* @author Volker Berlin
*/
public class ExpressionFunctionLeft extends ExpressionFunctionReturnP1StringAndBinary {
final int getFunction() {
return SQLTokenizer.LEFT;
}
final boolean isNull() throws Exception {
return param1.isNull() || param2.isNull();
}
final byte[] getBytes() throws Exception{
if(isNull()) return null;
byte[] bytes = param1.getBytes();
int length = param2.getInt();
if(bytes.length <= length) return bytes;
byte[] b = new byte[length];
System.arraycopy(bytes, 0, b, 0, length);
return b;
}
final String getString() throws Exception {
if(isNull()) return null;
String str = param1.getString();
int length = param2.getInt();
length = Math.min( length, str.length() );
return str.substring(0,length);
}
}
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