/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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 Lesser General Public License for more details.
*
* Copyright (c) 2006 - 2013 Pentaho Corporation and Contributors. All rights reserved.
*/
package org.pentaho.reporting.libraries.formula.typing;
import org.pentaho.reporting.libraries.base.util.ObjectUtilities;
import org.pentaho.reporting.libraries.formula.EvaluationException;
import org.pentaho.reporting.libraries.formula.FormulaContext;
import org.pentaho.reporting.libraries.formula.util.NumberUtil;
import java.math.BigDecimal;
/**
* Creation-Date: 03.11.2006, 16:15:28
*
* @author Thomas Morgner
*/
public class DefaultComparator implements ExtendedComparator {
private FormulaContext context;
private static final int LESS = -1;
private static final int EQUAL = 0;
private static final int MORE = 1;
public DefaultComparator() {
}
public void inititalize( final FormulaContext context ) {
if ( context == null ) {
throw new NullPointerException();
}
this.context = context;
}
public boolean isEqual( final Type type1, final Object value1,
final Type type2, final Object value2 ) {
// this is rather easy. If at least one of the types is a numeric,
// try to compare them as numbers. (And here it gets messy.)
if ( ObjectUtilities.equal( value1, value2 ) ) {
return true;
}
final TypeRegistry typeRegistry = context.getTypeRegistry();
if ( type1.isFlagSet( Type.NUMERIC_TYPE ) || value1 instanceof Number ||
type2.isFlagSet( Type.NUMERIC_TYPE ) || value2 instanceof Number ) {
try {
final Number number1 = typeRegistry.convertToNumber( type1, value1 );
final Number number2 = typeRegistry.convertToNumber( type2, value2 );
final BigDecimal bd1 = NumberUtil.getAsBigDecimal( number1 );
final BigDecimal bd2 = NumberUtil.getAsBigDecimal( number2 );
if ( bd1.signum() != bd2.signum() ) {
return false;
}
return bd1.compareTo( bd2 ) == 0;
} catch ( EvaluationException nfe ) {
// ignore ..
}
}
if ( type1.isFlagSet( Type.TEXT_TYPE ) || type2.isFlagSet( Type.TEXT_TYPE ) ) {
String text1 = null;
String text2 = null;
try {
// Convert both values to text ..
text1 = typeRegistry.convertToText( type1, value1 );
text2 = typeRegistry.convertToText( type2, value2 );
} catch ( EvaluationException nfe ) {
// ignore ..
}
if ( text1 == null && text2 == null ) {
return true;
}
if ( text1 == null || text2 == null ) {
return false;
}
return ObjectUtilities.equal( text1, text2 );
}
// Fall back to Java's equals method and hope the best ..
return ( ObjectUtilities.equal( value1, value2 ) );
}
/**
* Returns null, if the types are not comparable and are not convertible at all.
*
* @param type1
* @param value1
* @param type2
* @param value2
* @return
*/
public int compare( final Type type1, final Object value1,
final Type type2, final Object value2 ) {
// this is rather easy. If at least one of the types is a numeric,
// try to compare them as numbers. (And here it gets messy.)
if ( value1 == null && value2 == null ) {
return DefaultComparator.EQUAL;
}
if ( value1 == null ) {
return DefaultComparator.LESS;
}
if ( value2 == null ) {
return DefaultComparator.MORE;
}
// First, we try to compare both types directly. This is the least-expensive
// solution, as it does
// not include any conversion operations ..
if ( type1.isFlagSet( Type.SCALAR_TYPE ) && type2.isFlagSet( Type.SCALAR_TYPE ) ) {
// this is something else
if ( value1 instanceof Comparable && value2 instanceof Comparable ) {
final Comparable c1 = (Comparable) value1;
try {
final int result = c1.compareTo( value2 );
if ( result == 0 ) {
return DefaultComparator.EQUAL;
} else if ( result > 0 ) {
return DefaultComparator.MORE;
} else {
return DefaultComparator.LESS;
}
} catch ( Exception e ) {
// ignore any exception ..
}
}
}
// Next, we check the types on a numeric level.
final TypeRegistry typeRegistry = context.getTypeRegistry();
if ( type1.isFlagSet( Type.NUMERIC_TYPE ) || value1 instanceof Number ||
type2.isFlagSet( Type.NUMERIC_TYPE ) || value2 instanceof Number ) {
try {
final Number number1 = typeRegistry.convertToNumber( type1, value1 );
final Number number2 = typeRegistry.convertToNumber( type2, value2 );
final BigDecimal bd1 = NumberUtil.getAsBigDecimal( number1 );
final BigDecimal bd2 = NumberUtil.getAsBigDecimal( number2 );
if ( bd1.signum() != bd2.signum() ) {
if ( bd1.signum() < 0 ) {
return DefaultComparator.LESS;
} else if ( bd1.signum() > 0 ) {
return DefaultComparator.MORE;
}
}
final int result = bd1.compareTo( bd2 );
if ( result == 0 ) {
return DefaultComparator.EQUAL;
}
if ( result > 0 ) {
return DefaultComparator.MORE;
}
return DefaultComparator.LESS;
} catch ( EvaluationException nfe ) {
// Ignore ..
}
}
// And finally convert them to text and compare the text values ..
// Convert both values to text ..
String text1 = null;
String text2 = null;
try {
text1 = typeRegistry.convertToText( type1, value1 );
text2 = typeRegistry.convertToText( type2, value2 );
} catch ( EvaluationException e ) {
// failure here can be ignored.
}
if ( text1 == null && text2 == null ) {
return DefaultComparator.EQUAL;
}
if ( text1 == null ) {
return DefaultComparator.LESS;
}
if ( text2 == null ) {
return DefaultComparator.MORE;
}
final int result = text1.compareTo( text2 );
if ( result == 0 ) {
return DefaultComparator.EQUAL;
} else if ( result > 0 ) {
return DefaultComparator.MORE;
} else {
return DefaultComparator.LESS;
}
}
}