DBGreaterThanOperator.java

/*
 * Copyright 2013 Gregory Graham.
 *
 * 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 nz.co.gregs.dbvolution.operators;

import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import nz.co.gregs.dbvolution.datatypes.QueryableDatatypeSyncer.DBSafeInternalQDTAdaptor;
import nz.co.gregs.dbvolution.databases.definitions.DBDefinition;
import nz.co.gregs.dbvolution.expressions.BooleanExpression;
import nz.co.gregs.dbvolution.expressions.DBExpression;
import nz.co.gregs.dbvolution.expressions.DateExpression;
import nz.co.gregs.dbvolution.expressions.IntegerExpression;
import nz.co.gregs.dbvolution.results.DateResult;
import nz.co.gregs.dbvolution.expressions.NumberExpression;
import nz.co.gregs.dbvolution.expressions.RangeExpression;
import nz.co.gregs.dbvolution.results.NumberResult;
import nz.co.gregs.dbvolution.expressions.StringExpression;
import nz.co.gregs.dbvolution.results.IntegerResult;
import nz.co.gregs.dbvolution.results.StringResult;

/**
 * Implements GREATERTHAN for all types that support it.
 *
 * @author Gregory Graham
 */
public class DBGreaterThanOperator extends DBOperator {

	private static final long serialVersionUID = 1L;

	/**
	 * Implements GREATERTHAN for all types that support it.
	 *
	 * @param greaterThanThis the value to compare all other values against
	 */
	@SuppressFBWarnings(
			value = "NP_LOAD_OF_KNOWN_NULL_VALUE",
			justification = "Null is a valid value in databases")
	public DBGreaterThanOperator(DBExpression greaterThanThis) {
		super(greaterThanThis == null ? greaterThanThis : greaterThanThis.copy());
	}

	@Override
	public DBGreaterThanOperator copyAndAdapt(DBSafeInternalQDTAdaptor typeAdaptor) {
		DBGreaterThanOperator op = new DBGreaterThanOperator(typeAdaptor.convert(getFirstValue()));
		op.invertOperator = this.invertOperator;
		op.includeNulls = this.includeNulls;
		return op;
	}

	@Override
	public BooleanExpression generateWhereExpression(DBDefinition db, DBExpression column) {
		DBExpression genericExpression = column;
		BooleanExpression op = BooleanExpression.trueExpression();
		if (genericExpression instanceof StringExpression) {
			StringExpression stringExpression = (StringExpression) genericExpression;
			op = stringExpression.bracket().isGreaterThan((StringResult) getFirstValue());
		} else if (genericExpression instanceof NumberExpression) {
			NumberExpression numberExpression = (NumberExpression) genericExpression;
			op = numberExpression.isGreaterThan((NumberResult) getFirstValue());
		} else if (genericExpression instanceof IntegerExpression) {
			IntegerExpression numberExpression = (IntegerExpression) genericExpression;
			op = numberExpression.isGreaterThan((IntegerResult) getFirstValue());
		} else if (genericExpression instanceof DateExpression) {
			DateExpression dateExpression = (DateExpression) genericExpression;
			op = dateExpression.isGreaterThan((DateResult) getFirstValue());
		} else if (genericExpression instanceof RangeExpression) {
			RangeExpression expr = (RangeExpression) genericExpression;
			op = expr.is(getFirstValue());
		}
		return this.invertOperator ? op.not() : op;
	}
}