Assertion.java

/**
 * Copyright (c) 2013, Andre Steingress
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
 * following conditions are met:
 *
 * 1.) Redistributions of source code must retain the above copyright notice, this list of conditions and the following
 * disclaimer.
 * 2.) Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
 * disclaimer in the documentation and/or other materials provided with the distribution.
 * 3.) Neither the name of Andre Steingress nor the names of its contributors may be used to endorse or
 * promote products derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.gcontracts.domain;

import org.codehaus.groovy.ast.expr.BinaryExpression;
import org.codehaus.groovy.ast.expr.BooleanExpression;
import org.codehaus.groovy.ast.expr.ConstantExpression;
import org.codehaus.groovy.ast.stmt.BlockStatement;
import org.codehaus.groovy.syntax.Token;
import org.codehaus.groovy.syntax.Types;
import org.gcontracts.util.Validate;

/**
 * <p>Base class for all assertion types.</p>
 *
 * @author ast
 *
 * @param <T>
 */
public abstract class Assertion<T extends Assertion> {

    private BlockStatement originalBlockStatement;
    private BooleanExpression booleanExpression;

    public Assertion()  {
        this.booleanExpression = new BooleanExpression(ConstantExpression.TRUE);
    }

    public Assertion(final BlockStatement blockStatement, final BooleanExpression booleanExpression)  {
        Validate.notNull(booleanExpression);

        this.originalBlockStatement = blockStatement; // the BlockStatement might be null! we do not always have the original expression available
        this.booleanExpression = booleanExpression;
    }

    public BooleanExpression booleanExpression() { return booleanExpression; }
    public BlockStatement originalBlockStatement() { return originalBlockStatement; }

    public void renew(BooleanExpression booleanExpression)  {
        Validate.notNull(booleanExpression);

        // don't renew the source position to keep the new assertion expression without source code replacement
        // booleanExpression.setSourcePosition(this.booleanExpression);

        this.booleanExpression = booleanExpression;
    }

    public void and(T other) {
        Validate.notNull(other);

        BooleanExpression newBooleanExpression =
                new BooleanExpression(
                        new BinaryExpression(
                                booleanExpression(),
                                Token.newSymbol(Types.LOGICAL_AND, -1, -1),
                                other.booleanExpression()
                        )
                );
        newBooleanExpression.setSourcePosition(booleanExpression());

        renew(newBooleanExpression);
    }

    public void or(T other) {
        Validate.notNull(other);

        BooleanExpression newBooleanExpression =
                new BooleanExpression(
                        new BinaryExpression(
                                booleanExpression(),
                                Token.newSymbol(Types.LOGICAL_OR, -1, -1),
                                other.booleanExpression()
                        )
                );
        newBooleanExpression.setSourcePosition(booleanExpression());

        renew(newBooleanExpression);
    }
}