FoldOperatorProcessor.java

/**
 * Copyright 2011-2017 Asakusa Framework Team.
 *
 * 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.asakusafw.compiler.operator.processor;

import com.asakusafw.compiler.common.Precondition;
import com.asakusafw.compiler.common.TargetOperator;
import com.asakusafw.compiler.operator.AbstractOperatorProcessor;
import com.asakusafw.compiler.operator.ExecutableAnalyzer;
import com.asakusafw.compiler.operator.ExecutableAnalyzer.ShuffleKeySpec;
import com.asakusafw.compiler.operator.ExecutableAnalyzer.TypeConstraint;
import com.asakusafw.compiler.operator.OperatorMethodDescriptor;
import com.asakusafw.compiler.operator.OperatorMethodDescriptor.Builder;
import com.asakusafw.vocabulary.flow.graph.FlowBoundary;
import com.asakusafw.vocabulary.operator.Fold;


/**
 * Processes {@link Fold} operators.
 */
@TargetOperator(Fold.class)
public class FoldOperatorProcessor extends AbstractOperatorProcessor {

    @Override
    public OperatorMethodDescriptor describe(Context context) {
        Precondition.checkMustNotBeNull(context, "context"); //$NON-NLS-1$

        ExecutableAnalyzer a = new ExecutableAnalyzer(context.environment, context.element);
        if (a.isAbstract()) {
            a.error(Messages.getString("FoldOperatorProcessor.errorAbstract")); //$NON-NLS-1$
        }
        if (a.getReturnType().isVoid() == false) {
            a.error(Messages.getString("FoldOperatorProcessor.errorNotVoid")); //$NON-NLS-1$
        }
        TypeConstraint left = a.getParameterType(0);
        if (left.isModel() == false) {
            a.error(0, Messages.getString("FoldOperatorProcessor.errorNotModelLeft")); //$NON-NLS-1$
        }
        TypeConstraint right = a.getParameterType(1);
        if (right.isModel() == false) {
            a.error(1, Messages.getString("FoldOperatorProcessor.errorNotModelRight")); //$NON-NLS-1$
        }
        for (int i = 2, n = a.countParameters(); i < n; i++) {
            if (a.getParameterType(i).isBasic() == false) {
                a.error(i, Messages.getString("FoldOperatorProcessor.errorInvalidOptionParameter")); //$NON-NLS-1$
            }
        }
        if (a.hasError()) {
            return null;
        }

        if (context.environment.getTypeUtils().isSameType(left.getType(), right.getType()) == false) {
            a.error(1, Messages.getString("FoldOperatorProcessor.errorInconsistentInput")); //$NON-NLS-1$
        }
        ShuffleKeySpec foldKey = a.getParameterKeySpec(0);
        if (foldKey == null) {
            a.error(Messages.getString("FoldOperatorProcessor.errorMissingKeyAnnotation")); //$NON-NLS-1$
        }
        a.validateShuffleKeys(foldKey);
        Fold annotation = context.element.getAnnotation(Fold.class);
        if (annotation == null) {
            a.error(Messages.getString("FoldOperatorProcessor.errorInvalidAnnotation")); //$NON-NLS-1$
            return null;
        }
        OperatorProcessorUtil.checkPortName(a, new String[] {
                annotation.outputPort(),
        });
        if (a.hasError()) {
            return null;
        }
        assert foldKey != null;

        Builder builder = new Builder(getTargetAnnotationType(), context);
        builder.addAttribute(FlowBoundary.SHUFFLE);
        builder.addAttribute(a.getObservationCount());
        builder.addAttribute(annotation.partialAggregation());
        builder.setDocumentation(a.getExecutableDocument());
        builder.addInput(
                a.getParameterDocument(1),
                Fold.INPUT,
                a.getParameterType(1).getType(),
                1,
                foldKey.getKey());
        builder.addOutput(
                Messages.getString("FoldOperatorProcessor.javadocOutput"), //$NON-NLS-1$
                annotation.outputPort(),
                a.getParameterType(0).getType(),
                Fold.INPUT,
                0);
        for (int i = 2, n = a.countParameters(); i < n; i++) {
            builder.addParameter(
                    a.getParameterDocument(i),
                    a.getParameterName(i),
                    a.getParameterType(i).getType(),
                    i);
        }
        return builder.toDescriptor();
    }
}