com.cloudera.nav.sdk.client.QueryUtils.java Source code

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Here is the source code for com.cloudera.nav.sdk.client.QueryUtils.java

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/*
 * Copyright (c) 2015 Cloudera, Inc.
 *
 * 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.cloudera.nav.sdk.client;

import com.google.common.base.Joiner;

import java.util.Collection;

import org.apache.commons.lang.StringUtils;

/**
 * A set of functions for forming Solr queries.
 */
public class QueryUtils {

    /**
     * Makes a conjunctive "AND" Solr query with two clauses.
     *
     * @param q1 Solr query string
     * @param q2 Solr query string
     * @return (q1) AND (q2)
     */
    public static String conjoinSolrQueries(String q1, String q2) {
        if (StringUtils.isEmpty(q1)) {
            return q2;
        }
        if (StringUtils.isEmpty(q2)) {
            return q1;
        }
        return q1 + " AND " + q2;
    }

    /**
     * Constructs a single conjunctive clause of values with "OR"
     *
     * @param fieldName field name that clause values can satisfy
     * @param values iterable of possible values
     * @return conjunctive clause string as fieldName:(a OR b ...)
     */
    public static String buildConjunctiveClause(String fieldName, Collection<String> values) {
        Joiner conjunctiveJoiner = Joiner.on(" OR ").skipNulls();
        return fieldName + ":(" + conjunctiveJoiner.join(values) + ")";
    }

    /**
     * Convert desired values to valid query string in solr syntax in
     * conjunctive normal form as sourceType:(i OR j ...) AND type:(a OR b ...)
     *
     * @param sourceTypes collection of sourceType field values
     * @param types collection of type field values
     * @return Conjunctive clauses of sourceTypes and types
     */
    public static String buildQuery(Collection<String> sourceTypes, Collection<String> types) {
        String sourceClause = buildConjunctiveClause("sourceType", sourceTypes);
        String typeClause = buildConjunctiveClause("type", types);
        return conjoinSolrQueries(sourceClause, typeClause);
    }
}