org.apache.cayenne.query.SQLTemplateMetadata Maven / Gradle / Ivy

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 *  or more contributor license agreements.  See the NOTICE file
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 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
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 *    http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.cayenne.query;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;

import org.apache.cayenne.map.EntityResolver;
import org.apache.cayenne.map.ObjEntity;

/**
 * @since 3.0
 */
class SQLTemplateMetadata extends BaseQueryMetadata {

    boolean resolve(Object root, EntityResolver resolver, SQLTemplate query) {

        if (super.resolve(root, resolver, null)) {

            resultSetMapping = query.getResult() != null ? query
                    .getResult()
                    .getResolvedComponents(resolver) : null;

            // generate unique cache key...
            if (QueryCacheStrategy.NO_CACHE == getCacheStrategy()) {

            }
            else {

                // create a unique key based on entity, SQL, and parameters

                StringBuilder key = new StringBuilder();
                ObjEntity entity = getObjEntity();
                if (entity != null) {
                    key.append(entity.getName());
                }
                else if (dbEntity != null) {
                    key.append("db:").append(dbEntity.getName());
                }

                if (query.getDefaultTemplate() != null) {
                    key.append('/').append(query.getDefaultTemplate());
                }

                Map parameters = query.getParameters();
                if (!parameters.isEmpty()) {

                    List keys = new ArrayList(parameters.keySet());
                    Collections.sort(keys);

                    for (String parameterKey : keys) {
                        key.append('/').append(parameterKey).append('=').append(
                                parameters.get(parameterKey));
                    }
                }
                
                if (query.getFetchOffset() > 0 || query.getFetchLimit() > 0) {
                    key.append('/');
                    if (query.getFetchOffset() > 0) {
                        key.append('o').append(query.getFetchOffset());
                    }
                    if (query.getFetchLimit() > 0) {
                        key.append('l').append(query.getFetchLimit());
                    }
                }

                this.cacheKey = key.toString();
            }

            return true;
        }

        return false;
    }
}