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ActiveMQ example source code file (PropertiesViewFilter.java)

This example ActiveMQ source code file (PropertiesViewFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - ActiveMQ tags/keywords

arraylist, exception, hashmap, iterator, list, list, map, object, object, propertiesviewfilter, propertiesviewfilter, queryfilter, queryfilter, set, util

The ActiveMQ PropertiesViewFilter.java source code

/**
 * 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.activemq.console.filter;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class PropertiesViewFilter implements QueryFilter {
    protected QueryFilter next;
    protected Set viewFilter;

    /**
     * Creates a filter that will select the properties of a map object to view
     * 
     * @param next - the next query filter that will return a collection of maps
     */
    public PropertiesViewFilter(QueryFilter next) {
        this(null, next);
    }

    /**
     * Creates a filter that will select the properties of a map object to view
     * 
     * @param viewFilter - the properties to view
     * @param next - the next query filter that will return a collection of maps
     */
    public PropertiesViewFilter(Set viewFilter, QueryFilter next) {
        this.next = next;
        this.viewFilter = viewFilter;
    }

    /**
     * Filter the properties to view of the query result
     * 
     * @param query - the query string
     * @return list of objects that has been view filtered
     */
    public List<Map query(String query) throws Exception {
        return filterViewCollection(next.query(query), viewFilter);
    }

    /**
     * Filter the properties to view of the query result
     * 
     * @param queries - the query map
     * @return list of objects that has been view filtered
     * @throws Exception
     */
    public List<Map query(List queries) throws Exception {
        return filterViewCollection(next.query(queries), viewFilter);
    }

    /**
     * Filter the view of each element in the collection
     * 
     * @param result - the lists to filter the view from
     * @param viewFilter - the views to select
     * @return list of objects whose view has been filtered
     */
    protected List<Map filterViewCollection(Collection> result, Set viewFilter) {
        // Use a list to allow duplicate entries
        List<Map newCollection = new ArrayList>();

        for (Iterator<Map i = result.iterator(); i.hasNext();) {
            newCollection.add(filterView(i.next()));
        }

        return newCollection;
    }

    /**
     * Select only the attributes to view from the map data
     * 
     * @param data - data to filter the view from
     * @return - data with the view filtered
     */
    protected Map<Object, Object> filterView(Map data) {
        // If no view specified, display all attributes
        if (viewFilter == null || viewFilter.isEmpty()) {
            return data;
        }

        Map<Object, Object> newData;
        try {
            // Lets try to use the same class as the original
            newData = data.getClass().newInstance();
        } catch (Exception e) {
            // Lets use a default HashMap
            newData = new HashMap<Object, Object>();
        }

        // Filter the keys to view
        for (Iterator i = viewFilter.iterator(); i.hasNext();) {
            Object key = i.next();
            Object val = data.get(key);

            if (val != null) {
                newData.put(key, val);
            }
        }

        return newData;
    }

}

Other ActiveMQ examples (source code examples)

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