com.github.jakubkolar.autobuilder.impl.ResolverChain.java Source code

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Here is the source code for com.github.jakubkolar.autobuilder.impl.ResolverChain.java

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/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2016 Jakub Kolar
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.github.jakubkolar.autobuilder.impl;

import com.github.jakubkolar.autobuilder.spi.ValueResolver;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableList.Builder;
import org.apache.commons.lang3.SystemUtils;

import javax.annotation.Nullable;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.util.Collection;
import java.util.List;
import java.util.Optional;

class ResolverChain implements ValueResolver {

    private final ImmutableList<ValueResolver> resolvers;

    public ResolverChain(ValueResolver... resolvers) {
        this.resolvers = new Builder<ValueResolver>().add(resolvers).build();
    }

    private ResolverChain(List<ValueResolver> oldResolvers, ValueResolver... newResolvers) {
        this.resolvers = new Builder<ValueResolver>().addAll(oldResolvers).add(newResolvers).build();
    }

    @Nullable
    @Override
    public <T> T resolve(Class<T> type, Optional<Type> typeInfo, String name, Collection<Annotation> annotations) {
        StringBuilder failedResolvers = new StringBuilder();
        for (ValueResolver resolver : resolvers) {
            try {
                return resolver.resolve(type, typeInfo, name, annotations);
            } catch (UnsupportedOperationException e) {
                // TODO: it is probably better if the messages are just logged as a debug output
                failedResolvers.append('\t').append(resolver.getClass().getSimpleName()).append(": ")
                        .append(e.getMessage()).append(SystemUtils.LINE_SEPARATOR);
                // Try next resolver
            }
        }

        throw new UnsupportedOperationException(
                "No suitable resolver found: " + SystemUtils.LINE_SEPARATOR + failedResolvers);
    }

    public ResolverChain add(ValueResolver resolver) {
        return new ResolverChain(resolvers, resolver);
    }

}