Implementazione di un valutatore del predicato personalizzato per il Generatore di query implementing-a-custom-predicate-evaluator-for-the-query-builder

@@ -120,6 +120,12 @@
             <scope>provided</scope>
         <dependency>
+            <groupid>com.day.cq</groupid>
+            <artifactid>cq-search</artifactid>
+            <version>5.6.4</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
             <groupid>junit</groupid>
             <artifactid>junit</artifactid>
             <version>3.8.1</version></dependency>

@@ -19,8 +19,11 @@
  */
 package com.adobe.aem.docs.search;
+import org.apache.felix.scr.annotations.Component;
+import com.day.cq.search.eval.AbstractPredicateEvaluator;
+@Component(metatype = false, factory = "com.day.cq.search.eval.PredicateEvaluator/repli")
 public class ReplicationPredicateEvaluator extends AbstractPredicateEvaluator {

  }

/*
 * #%L
 * aem-docs-custom-predicate-evaluator
 * %%
 * Copyright (C) 2013 Adobe Research
 * %%
 * 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.
 * #L%
 */

package com.adobe.aem.docs.search;

import org.apache.felix.scr.annotations.Component;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;


import com.day.cq.search.Predicate;

import com.day.cq.search.eval.AbstractPredicateEvaluator;

import com.day.cq.search.eval.EvaluationContext;


@Component(metatype = false, factory = "com.day.cq.search.eval.PredicateEvaluator/repli")

public class ReplicationPredicateEvaluator extends AbstractPredicateEvaluator {

    static final String PE_NAME = "replic";

    static final String PN_LAST_REPLICATED_BY = "cq:lastReplicatedBy";

    static final String PN_LAST_REPLICATED = "cq:lastReplicated";

    static final String PN_LAST_REPLICATED_ACTION = "cq:lastReplicationAction";

    static final String PREDICATE_BY = "by";

    static final String PREDICATE_SINCE = "since";

    static final String PREDICATE_SINCE_OP = " >= ";

    static final String PREDICATE_ACTION = "action";


    Logger log = LoggerFactory.getLogger(getClass());

    /**
     * Returns a XPath expression filtering by replication metadata.
     *
     * @see com.day.cq.search.eval.AbstractPredicateEvaluator#getXPathExpression(com.day.cq.search.Predicate,
     *      com.day.cq.search.eval.EvaluationContext)
     */

    @Override

    public String getXPathExpression(Predicate predicate,

            EvaluationContext context) {

        log.debug("predicate {}", predicate);


        String date = predicate.get(PREDICATE_SINCE);

        String user = predicate.get(PREDICATE_BY);

        String action = predicate.get(PREDICATE_ACTION);


        StringBuilder sb = new StringBuilder();


        if (date != null) {

            sb.append(PN_LAST_REPLICATED).append(PREDICATE_SINCE_OP);

            sb.append("xs:dateTime('").append(date).append("')");

        }

        if (user != null) {

            addAndOperator(sb);

            sb.append(PN_LAST_REPLICATED_BY);

            sb.append("='").append(user).append("'");

        }

        if (action != null) {

            addAndOperator(sb);

            sb.append(PN_LAST_REPLICATED_ACTION);

            sb.append("='").append(action).append("'");

        }

        String xpath = sb.toString();

        log.debug("xpath **{}**", xpath);

        return xpath;

    }

    /**
     * Add an and operator if the builder is not empty.
     *
     * @param sb a {@link StringBuilder} containing the query under construction
     */

    private void addAndOperator(StringBuilder sb) {

        if (sb.length() != 0) {

            sb.append(" and ");

        }

    }

}