ParameterTypeChanged.java

/*
 * Copyright 2014 Lukas Krejci
 *
 * 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 org.revapi.java.checks.methods;

import java.util.Collections;
import java.util.EnumSet;
import java.util.List;

import javax.annotation.Nullable;

import org.revapi.Difference;
import org.revapi.java.spi.CheckBase;
import org.revapi.java.spi.Code;
import org.revapi.java.spi.JavaMethodElement;
import org.revapi.java.spi.JavaMethodParameterElement;
import org.revapi.java.spi.Util;

/**
 * @author Lukas Krejci
 * @since 0.1
 */
public final class ParameterTypeChanged extends CheckBase {

    private boolean skip;

    @Override
    public EnumSet<Type> getInterest() {
        return EnumSet.of(Type.METHOD, Type.METHOD_PARAMETER);
    }

    @Override
    protected void doVisitMethod(@Nullable JavaMethodElement oldMethod, @Nullable JavaMethodElement newMethod) {
        skip = oldMethod == null || newMethod == null ||
                oldMethod.getModelRepresentation().getParameterTypes().size() !=
                        newMethod.getModelRepresentation().getParameterTypes().size();
    }

    @Override
    protected void doVisitMethodParameter(@Nullable JavaMethodParameterElement oldParameter,
        @Nullable JavaMethodParameterElement newParameter) {

        if (skip || oldParameter == null || newParameter == null) {
            //will be handled by nof parameters changed...
            return;
        }

        if (isBothPrivate(oldParameter.getParent(), newParameter.getParent())) {
            return;
        }

        String oldType = Util.toUniqueString(oldParameter.getModelRepresentation());
        String newType = Util.toUniqueString(newParameter.getModelRepresentation());

        if (!oldType.equals(newType)) {
            pushActive(oldParameter, newParameter);
        }
    }

    @Nullable
    @Override
    protected List<Difference> doEnd() {

        ActiveElements<JavaMethodParameterElement> params = popIfActive();
        if (params == null) {
            return null;
        }

        String oldType = Util.toHumanReadableString(params.oldElement.getModelRepresentation());
        String newType = Util.toHumanReadableString(params.newElement.getModelRepresentation());

        String oldErasedType = Util.toUniqueString(params.oldElement.getTypeEnvironment().getTypeUtils()
                .erasure(params.oldElement.getModelRepresentation()));
        String newErasedType = Util.toUniqueString(params.newElement.getTypeEnvironment().getTypeUtils()
                .erasure(params.newElement.getModelRepresentation()));

        if (!oldErasedType.equals(newErasedType)) {
            return Collections.singletonList(createDifference(Code.METHOD_PARAMETER_TYPE_CHANGED,
                    Code.attachmentsFor(params.oldElement, params.newElement,
                            "oldType", oldType,
                            "newType", newType)));
        } else {
            return Collections.singletonList(createDifference(Code.METHOD_PARAMETER_TYPE_PARAMETER_CHANGED,
                    Code.attachmentsFor(params.oldElement, params.newElement,
                            "oldType", oldType,
                            "newType", newType)));
        }
    }
}