DataJsonFormatter.java

/* 
 *
 * SchemaCrawler
 * http://sourceforge.net/projects/schemacrawler
 * Copyright (c) 2000-2013, Sualeh Fatehi.
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 */

package schemacrawler.tools.text.operation;


import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import schemacrawler.schema.Table;
import schemacrawler.schemacrawler.SchemaCrawlerException;
import schemacrawler.tools.options.OutputOptions;
import schemacrawler.tools.text.base.BaseJsonFormatter;
import schemacrawler.tools.text.utility.org.json.JSONArray;
import schemacrawler.tools.text.utility.org.json.JSONException;
import schemacrawler.tools.text.utility.org.json.JSONObject;
import schemacrawler.tools.traversal.DataTraversalHandler;

/**
 * Text formatting of data.
 * 
 * @author Sualeh Fatehi
 */
final class DataJsonFormatter
  extends BaseJsonFormatter<OperationOptions>
  implements DataTraversalHandler
{

  private final Operation operation;
  private final JSONArray jsonDataArray;

  /**
   * Text formatting of data.
   * 
   * @param operation
   *        Options for text formatting of data
   * @param options
   *        Options for text formatting of data
   * @param outputOptions
   *        Options for text formatting of data
   */
  DataJsonFormatter(final Operation operation,
                    final OperationOptions options,
                    final OutputOptions outputOptions)
    throws SchemaCrawlerException
  {
    super(options, /* printVerboseDatabaseInfo */false, outputOptions);
    this.operation = operation;

    jsonDataArray = new JSONArray();
    try
    {
      if (operation != null)
      {
        jsonRoot.put("description", operation.getDescription());
      }
      jsonRoot.put("data", jsonDataArray);
    }
    catch (final JSONException e)
    {
      throw new SchemaCrawlerException(e.getMessage(), e);
    }
  }

  /**
   * {@inheritDoc}
   * 
   * @see schemacrawler.tools.traversal.DataTraversalHandler#handleData(schemacrawler.tools.text.operation.Query,
   *      java.sql.ResultSet)
   */
  @Override
  public void handleData(final Query query, final ResultSet rows)
    throws SchemaCrawlerException
  {
    String title;
    if (query != null)
    {
      title = query.getName();
    }
    else
    {
      title = "";
    }

    handleData(title, rows);
  }

  /**
   * {@inheritDoc}
   * 
   * @see schemacrawler.tools.traversal.DataTraversalHandler#handleData(schemacrawler.schema.Table,
   *      java.sql.ResultSet)
   */
  @Override
  public void handleData(final Table table, final ResultSet rows)
    throws SchemaCrawlerException
  {
    final String tableName;
    if (table != null)
    {
      if (options.isShowUnqualifiedNames())
      {
        tableName = table.getName();
      }
      else
      {
        tableName = table.getFullName();
      }
    }
    else
    {
      tableName = "";
    }

    handleData(tableName, rows);
  }

  /**
   * Handles an aggregate operation, such as a count, for a given table.
   * 
   * @param title
   *        Title
   * @param results
   *        Results
   */
  private long handleAggregateOperationForTable(final String title,
                                                final ResultSet results)
    throws SchemaCrawlerException
  {
    try
    {
      long aggregate = 0;
      if (results.next())
      {
        aggregate = results.getLong(1);
      }
      return aggregate;
    }
    catch (final SQLException e)
    {
      throw new SchemaCrawlerException("Could not obtain aggregate data", e);
    }
  }

  private void handleData(final String title, final ResultSet rows)
    throws SchemaCrawlerException
  {
    if (rows == null)
    {
      return;
    }

    try
    {
      final JSONObject jsonData = new JSONObject();
      jsonData.put("title", title);

      if (operation == Operation.count)
      {
        final long aggregate = handleAggregateOperationForTable(title, rows);
        jsonData.put("value", aggregate);
      }
      else
      {
        try
        {
          final DataResultSet dataRows = new DataResultSet(rows,
                                                           options.isShowLobs());

          jsonData.put("columnNames", new JSONArray(dataRows.getColumnNames()));

          final JSONArray jsonRows = iterateRows(dataRows);
          jsonData.put("rows", jsonRows);
        }
        catch (final SQLException e)
        {
          throw new SchemaCrawlerException(e.getMessage(), e);
        }
      }

      jsonDataArray.put(jsonData);
    }
    catch (final JSONException e)
    {
      throw new SchemaCrawlerException("Could not convert data to JSON", e);
    }

  }

  private JSONArray iterateRows(final DataResultSet dataRows)
    throws SQLException
  {
    final JSONArray jsonRows = new JSONArray();
    while (dataRows.next())
    {
      final List currentRow = dataRows.row();
      jsonRows.put(new JSONArray(currentRow));
    }
    return jsonRows;
  }
}