Class JDBCCategoryDataset

All Implemented Interfaces:
ObjectInputValidation, Serializable, Cloneable, CategoryDataset, Dataset, KeyedValues2D, Values2D

public class JDBCCategoryDataset
extends DefaultCategoryDataset
A CategoryDataset implementation over a database JDBC result set. The dataset is populated via a call to executeQuery with the string sql query. The sql query must return at least two columns. The first column will be the category name and remaining columns values. executeQuery can be called a number of times. The database connection is read-only and no write back facility exists.
Author:
Bryan Scott Changes ------- 24-Sep-2003 : Added clearing results from previous queries to executeQuery following being highlighted on online forum (BS);
See Also:
Serialized Form
  • Constructor Details

    • JDBCCategoryDataset

      public JDBCCategoryDataset​(String url, String driverName, String user, String passwd) throws ClassNotFoundException, SQLException
      Creates a new dataset with a database connection.
      Parameters:
      url - the URL of the database connection.
      driverName - the database driver class name.
      user - the database user.
      passwd - the database user's password.
      Throws:
      ClassNotFoundException - if the driver cannot be found.
      SQLException - if there is an error obtaining a connection to the database.
    • JDBCCategoryDataset

      public JDBCCategoryDataset​(Connection connection)
      Create a new dataset with the given database connection.
      Parameters:
      connection - the database connection.
    • JDBCCategoryDataset

      public JDBCCategoryDataset​(Connection connection, String query) throws SQLException
      Creates a new dataset with the given database connection, and executes the supplied query to populate the dataset.
      Parameters:
      connection - the connection.
      query - the query.
      Throws:
      SQLException - if there is a problem executing the query.
  • Method Details

    • getTranspose

      public boolean getTranspose()
      Returns a flag that controls whether or not the table values are transposed when added to the dataset.
      Returns:
      A boolean.
    • setTranspose

      public void setTranspose​(boolean transpose)
      Sets a flag that controls whether or not the table values are transposed when added to the dataset.
      Parameters:
      transpose - the flag.
    • executeQuery

      public void executeQuery​(String query) throws SQLException
      Populates the dataset by executing the supplied query against the existing database connection. If no connection exists then no action is taken.

      The results from the query are extracted and cached locally, thus applying an upper limit on how many rows can be retrieved successfully.

      Parameters:
      query - the query.
      Throws:
      SQLException - if there is a problem executing the query.
    • executeQuery

      public void executeQuery​(Connection con, String query) throws SQLException
      Populates the dataset by executing the supplied query against the existing database connection. If no connection exists then no action is taken.

      The results from the query are extracted and cached locally, thus applying an upper limit on how many rows can be retrieved successfully.

      Parameters:
      con - the connection.
      query - the query.
      Throws:
      SQLException - if there is a problem executing the query.