/*
* Copyright (c) 2011-2015 EPFL DATA Laboratory
* Copyright (c) 2014-2015 The Squall Collaboration (see NOTICE)
*
* All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ch.epfl.data.squall.expressions;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
import ch.epfl.data.squall.types.DateType;
import ch.epfl.data.squall.types.Type;
import ch.epfl.data.squall.visitors.ValueExpressionVisitor;
public class DateSum implements ValueExpression<Date> {
private static final long serialVersionUID = 1L;
private final Type<Date> _dc = new DateType();
private final ValueExpression<Date> _ve;
private final int _interval, _unit;
public DateSum(ValueExpression<Date> ve, int unit, int interval) {
_ve = ve;
_unit = unit;
_interval = interval;
}
@Override
public void accept(ValueExpressionVisitor vev) {
vev.visit(this);
}
@Override
public void changeValues(int i, ValueExpression<Date> newExpr) {
// nothing
}
@Override
public Date eval(List<String> tuple) {
final Date base = _ve.eval(tuple);
final Calendar c = Calendar.getInstance();
c.setTime(base);
c.add(_unit, _interval);
return c.getTime();
}
@Override
public String evalString(List<String> tuple) {
return _dc.toString(eval(tuple));
}
@Override
public List<ValueExpression> getInnerExpressions() {
final List<ValueExpression> result = new ArrayList<ValueExpression>();
result.add(_ve);
return result;
}
@Override
public Type getType() {
return _dc;
}
@Override
public void inverseNumber() {
// nothing
}
@Override
public boolean isNegative() {
// nothing
return false;
}
@Override
public String toString() {
final StringBuilder sb = new StringBuilder();
sb.append("DateSum ").append(_ve.toString());
sb.append(" interval ").append(_interval);
sb.append(" unit ").append(_unit);
return sb.toString();
}
}