KindChanged.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.classes;

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

import javax.lang.model.element.TypeElement;

import org.revapi.Difference;
import org.revapi.java.spi.CheckBase;
import org.revapi.java.spi.Code;
import org.revapi.java.spi.JavaTypeElement;

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

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

    @Override
    protected void doVisitClass(JavaTypeElement oldType, JavaTypeElement newType) {
        if (oldType != null && newType != null
                && oldType.getDeclaringElement().getKind() != newType.getDeclaringElement().getKind()
                && isBothAccessible(oldType, newType)) {
            pushActive(oldType, newType);
        }
    }

    @Override
    protected List<Difference> doEnd() {
        ActiveElements<JavaTypeElement> types = popIfActive();
        if (types != null) {
            TypeElement o = types.oldElement.getDeclaringElement();
            TypeElement n = types.newElement.getDeclaringElement();

            if (o.getKind() != n.getKind()) {
                Difference p = createDifference(Code.CLASS_KIND_CHANGED,
                        Code.attachmentsFor(types.oldElement, types.newElement,
                                "oldKind", kind(o),
                                "newKind", kind(n)));

                return Collections.singletonList(p);
            }
        }

        return null;
    }

    private String kind(TypeElement e) {
        switch (e.getKind()) {
            case CLASS:
                return "class";
            case INTERFACE:
                return "interface";
            case ANNOTATION_TYPE:
                return "@interface";
            case ENUM:
                return "enum";
            default:
                return "unexpected (" + e.getKind() + ")";
        }
    }
}