org.apache.lens.cube.parse.PruneCauses.java Source code

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Here is the source code for org.apache.lens.cube.parse.PruneCauses.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.lens.cube.parse;

import static java.util.stream.Collectors.toMap;

import static com.google.common.collect.Sets.newHashSet;

import java.io.ByteArrayOutputStream;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;

import org.apache.lens.cube.parse.CandidateTablePruneCause.CandidateTablePruneCode;
import org.apache.lens.server.api.error.LensException;

import org.apache.commons.lang.StringUtils;

import org.codehaus.jackson.annotate.JsonWriteNullProperties;
import org.codehaus.jackson.map.ObjectMapper;

import com.google.common.collect.Maps;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.Getter;
import lombok.NoArgsConstructor;

public class PruneCauses<T> extends HashMap<T, List<CandidateTablePruneCause>> {
    @Getter(lazy = true)
    private final HashMap<CandidateTablePruneCause, List<T>> reversed = reverse();
    @Getter(lazy = true)
    private final HashMap<String, List<CandidateTablePruneCause>> compact = computeCompact();
    @Getter(lazy = true)
    private final CandidateTablePruneCode maxCause = computeMaxCause();

    private HashMap<String, List<CandidateTablePruneCause>> computeCompact() {
        HashMap<String, List<CandidateTablePruneCause>> detailedMessage = Maps.newHashMap();
        for (Map.Entry<CandidateTablePruneCause, List<T>> entry : getReversed().entrySet()) {
            String key = StringUtils.join(entry.getValue(), ",");
            detailedMessage.computeIfAbsent(key, k -> new ArrayList<>()).add(entry.getKey());
        }
        return detailedMessage;
    }

    @Getter(lazy = true)
    private final BriefAndDetailedError jsonObject = toJsonObject();

    public void addPruningMsg(T table, CandidateTablePruneCause msg) {
        computeIfAbsent(table, x -> new ArrayList()).add(msg);
    }

    private HashMap<CandidateTablePruneCause, List<T>> reverse() {
        HashMap<CandidateTablePruneCause, List<T>> result = new HashMap<CandidateTablePruneCause, List<T>>();
        for (T key : keySet()) {
            for (CandidateTablePruneCause value : get(key)) {
                result.computeIfAbsent(value, k -> new ArrayList<>()).add(key);
            }
        }
        return result;
    }

    public BriefAndDetailedError toJsonObject() {
        return new BriefAndDetailedError(getBriefCause(), getCompact());
    }

    private CandidateTablePruneCode computeMaxCause() {
        CandidateTablePruneCode maxCause = CandidateTablePruneCode.values()[0];
        for (CandidateTablePruneCause cause : getReversed().keySet()) {
            if (cause.getCause().compareTo(maxCause) > 0) {
                maxCause = cause.getCause();
            }
        }
        return maxCause;
    }

    public String getBriefCause() {
        CandidateTablePruneCode maxCause = getReversed().keySet().stream().map(CandidateTablePruneCause::getCause)
                .max(Comparator.naturalOrder()).get();
        Map<CandidateTablePruneCause, String> maxCauseMap = Maps.newHashMap();
        for (Map.Entry<CandidateTablePruneCause, List<T>> entry : getReversed().entrySet()) {
            if (entry.getKey().getCause().equals(maxCause)) {
                maxCauseMap.put(entry.getKey(), StringUtils.join(entry.getValue(), ","));
            }
        }
        return maxCause.getBriefError(maxCauseMap.keySet());
    }

    public static void main(String[] args) {
        new BriefAndDetailedError();
    }

    String toJsonString() throws LensException {
        return getJsonObject().toJsonString();
    }

    @JsonWriteNullProperties(false)
    @Data
    @AllArgsConstructor
    @NoArgsConstructor
    public static final class BriefAndDetailedError {
        private String brief;
        private HashMap<String, List<CandidateTablePruneCause>> details;

        Map<HashSet<String>, List<CandidateTablePruneCause>> enhanced() {
            return getDetails().entrySet().stream()
                    .collect(toMap(o -> newHashSet(o.getKey().split(",")), Map.Entry::getValue));
        }

        String toJsonString() throws LensException {
            try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
                ObjectMapper mapper = new ObjectMapper();
                mapper.writeValue(out, this);
                return out.toString("UTF-8");
            } catch (Exception e) {
                throw new LensException("Error writing fact pruning messages", e);
            }
        }
    }
}