org.jfree.data.jdbc

Class JDBCPieDataset

public class JDBCPieDataset extends DefaultPieDataset

A PieDataset that reads data from a database via JDBC.

A query should be supplied that returns data in two columns, the first containing VARCHAR data, and the second containing numerical data. The data is cached in-memory and can be refreshed at any time.

Constructor Summary
JDBCPieDataset(String url, String driverName, String user, String password)
Creates a new JDBCPieDataset and establishes a new database connection.
JDBCPieDataset(Connection con)
Creates a new JDBCPieDataset using a pre-existing database connection.
JDBCPieDataset(Connection con, String query)
Creates a new JDBCPieDataset using a pre-existing database connection.
Method Summary
voidclose()
Close the database connection
voidexecuteQuery(String query)
ExecuteQuery will attempt execute the query passed to it against the existing database connection.
voidexecuteQuery(Connection con, String query)
ExecuteQuery will attempt execute the query passed to it against the existing database connection.

Constructor Detail

JDBCPieDataset

public JDBCPieDataset(String url, String driverName, String user, String password)
Creates a new JDBCPieDataset and establishes a new database connection.

Parameters: url the URL of the database connection. driverName the database driver class name. user the database user. password the database users password.

Throws: ClassNotFoundException if the driver cannot be found. SQLException if there is a problem obtaining a database connection.

JDBCPieDataset

public JDBCPieDataset(Connection con)
Creates a new JDBCPieDataset using a pre-existing database connection.

The dataset is initially empty, since no query has been supplied yet.

Parameters: con the database connection.

JDBCPieDataset

public JDBCPieDataset(Connection con, String query)
Creates a new JDBCPieDataset using a pre-existing database connection.

The dataset is initialised with the supplied query.

Parameters: con the database connection. query the database connection.

Throws: SQLException if there is a problem executing the query.

Method Detail

close

public void close()
Close the database connection

executeQuery

public void executeQuery(String query)
ExecuteQuery will attempt execute the query passed to it 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 to be executed.

Throws: SQLException if there is a problem executing the query.

executeQuery

public void executeQuery(Connection con, String query)
ExecuteQuery will attempt execute the query passed to it 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 to be executed con the connection the query is to be executed against

Throws: SQLException if there is a problem executing the query.

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