iciql/src/com/iciql/bytecode/Not.java

/*
 * Copyright 2004-2011 H2 Group.
 * Copyright 2011 James Moger.
 *
 * 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 com.iciql.bytecode;

import com.iciql.Query;
import com.iciql.SQLStatement;
import com.iciql.Token;

/**
 * A NOT condition.
 */
public class Not implements Token {

	private Token expr;

	private Not(Token expr) {
		this.expr = expr;
	}

	static Token get(Token expr) {
		if (expr instanceof Not) {
			return ((Not) expr).expr;
		} else if (expr instanceof Operation) {
			return ((Operation) expr).reverse();
		}
		return new Not(expr);
	}

	Token not() {
		return expr;
	}

	public <T> void appendSQL(SQLStatement stat, Query<T> query) {
		// untested
		stat.appendSQL("NOT(");
		expr.appendSQL(stat, query);
		stat.appendSQL(")");
	}

}