JsonRowMapper.java

/*
 * #%L
 * Service Activity Monitoring :: Server
 * %%
 * Copyright (C) 2011 - 2012 Talend 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.
 * #L%
 */
package org.talend.esb.sam.server.ui;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonPrimitive;
import com.google.gson.JsonSerializationContext;
import com.google.gson.JsonSerializer;

import java.lang.reflect.Type;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Timestamp;
import java.util.HashMap;
import java.util.Map;

import org.springframework.jdbc.core.ColumnMapRowMapper;
import org.springframework.jdbc.core.RowMapper;

/**
 * Intelligent mapper that tries to read all fields
 * from {@link ResultSet}.
 *
 * @author zubairov
 */
public class JsonRowMapper implements RowMapper<JsonObject> {

    @SuppressWarnings("serial")
    private static final Map<String, String> NAME_MAPPING = new HashMap<String, String>() {
        {
            put("ID", "id");
            put("MI_FLOW_ID", "flowID");
            put("EI_TIMESTAMP", "timestamp");
            put("EI_EVENT_TYPE", "type");
            put("MI_PORT_TYPE", "port");
            put("MI_OPERATION_NAME", "operation");
            put("MI_TRANSPORT_TYPE", "transport");
            put("ORIG_HOSTNAME", "host");
            put("ORIG_IP", "ip");
            put("ORIG_CUSTOM_ID", "customID");
            put("ORIG_PROCESS_ID", "process");
            put("ORIG_PRINCIPAL", "principal");
            put("MI_MESSAGE_ID", "messageID");
            put("CONTENT_CUT", "contentCut");
            put("MESSAGE_CONTENT", "content");
            put("CUST_KEY", "custKey");
            put("CUST_VALUE", "custValue");
        }
    };

    private final RowMapper<Map<String, Object>> nestedMapper = new ColumnMapRowMapper();

    private final Gson gson;

    /**
     * Instantiates a new json row mapper.
     */
    public JsonRowMapper() {
        GsonBuilder builder = new GsonBuilder();
        builder.registerTypeAdapter(Timestamp.class, new JsonSerializer<Timestamp>() {

            @Override
            public JsonElement serialize(Timestamp src, Type typeOfSrc,
                    JsonSerializationContext context) {
                return new JsonPrimitive(src.getTime());
            }
        });
        gson = builder.create();
    }

    /* (non-Javadoc)
     * @see org.springframework.jdbc.core.RowMapper#mapRow(java.sql.ResultSet, int)
     */
    @Override
    public JsonObject mapRow(ResultSet rs, int rowNum) throws SQLException {
        final Map<String, Object> map = nestedMapper.mapRow(rs, rowNum);

        JsonObject row = new JsonObject();
        for (String key : map.keySet()) {
            String jsonName = NAME_MAPPING.get(key);
            if (jsonName == null) {
                jsonName = key;
            }
            row.add(jsonName, gson.toJsonTree(map.get(key)));
        }
        return row;
    }

}