org.jfree.data.jdbc.JDBCCategoryDataset Maven / Gradle / Ivy
/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2020, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jfreechart/index.html
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
* Other names may be trademarks of their respective owners.]
*
* ------------------------
* JDBCCategoryDataset.java
* ------------------------
* (C) Copyright 2002-2008, by Bryan Scott and Contributors.
*
* Original Author: Bryan Scott; Andy;
* Contributor(s): David Gilbert (for Object Refinery Limited);
* Thomas Morgner;
*
* Changes
* -------
* 26-Apr-2002 : Creation based on JdbcXYDataSet, using code contributed from
* Andy;
* 13-Aug-2002 : Updated Javadocs, import statements and formatting (DG);
* 03-Sep-2002 : Added fix for bug 591385 (DG);
* 18-Sep-2002 : Updated to support BIGINT (BS);
* 16-Oct-2002 : Added fix for bug 586667 (DG);
* 03-Feb-2003 : Added Types.DECIMAL (see bug report 677814) (DG);
* 13-Jun-2003 : Added Types.TIME as suggest by Bryan Scott in the forum (DG);
* 30-Jun-2003 : CVS Write test (BS);
* 30-Jul-2003 : Added empty contructor and executeQuery(connection,string)
* method (BS);
* 29-Aug-2003 : Added a 'transpose' flag, so that data can be easily
* transposed if required (DG);
* 10-Sep-2003 : Added support for additional JDBC types (DG);
* 24-Sep-2003 : Added clearing results from previous queries to executeQuery
* following being highlighted on online forum (BS);
* 02-Dec-2003 : Throwing exceptions allows to handle errors, removed default
* constructor, as without a connection, a query can never be
* executed (TM);
* 04-Dec-2003 : Added missing Javadocs (DG);
* ------------- JFREECHART 1.0.0 ---------------------------------------------
* 08-Mar-2006 : Fixed bug 1445748 where an exception is thrown if
* executeQuery() is called more than once (DG);
*
*/
package org.jfree.data.jdbc;
import java.sql.Connection;
import java.sql.Date;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Types;
import org.jfree.data.category.CategoryDataset;
import org.jfree.data.category.DefaultCategoryDataset;
/**
* A {@link CategoryDataset} implementation over a database JDBC result set.
* The dataset is populated via a call to {@link #executeQuery(String)} 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 (each
* column represents a series). Subsequent calls to
* {@link #executeQuery(String)} will refresh the dataset.
*
* The database connection is read-only and no write back facility exists.
*
* NOTE: Many people have found this class too restrictive in general use.
* For the greatest flexibility, please consider writing your own code to read
* data from a{@code ResultSet} and populate a {@link DefaultCategoryDataset}
* directly.
*/
public class JDBCCategoryDataset extends DefaultCategoryDataset {
/** For serialization. */
static final long serialVersionUID = -3080395327918844965L;
/** The database connection. */
private transient Connection connection;
/**
* A flag the controls whether or not the table is transposed. The default
* is 'true' because this provides the behaviour described in the
* documentation.
*/
private boolean transpose = true;
/**
* Creates a new dataset with a database connection.
*
* @param url the URL of the database connection.
* @param driverName the database driver class name.
* @param user the database user.
* @param passwd the database user's password.
*
* @throws ClassNotFoundException if the driver cannot be found.
* @throws SQLException if there is an error obtaining a connection to the
* database.
*/
public JDBCCategoryDataset(String url,
String driverName,
String user,
String passwd)
throws ClassNotFoundException, SQLException {
Class.forName(driverName);
this.connection = DriverManager.getConnection(url, user, passwd);
}
/**
* Create a new dataset with the given database connection.
*
* @param connection the database connection.
*/
public JDBCCategoryDataset(Connection connection) {
if (connection == null) {
throw new NullPointerException("A connection must be supplied.");
}
this.connection = connection;
}
/**
* Creates a new dataset with the given database connection, and executes
* the supplied query to populate the dataset.
*
* @param connection the connection.
* @param query the query.
*
* @throws SQLException if there is a problem executing the query.
*/
public JDBCCategoryDataset(Connection connection, String query)
throws SQLException {
this(connection);
executeQuery(query);
}
/**
* Returns a flag that controls whether or not the table values are
* transposed when added to the dataset.
*
* @return A boolean.
*/
public boolean getTranspose() {
return this.transpose;
}
/**
* Sets a flag that controls whether or not the table values are transposed
* when added to the dataset.
*
* @param transpose the flag.
*/
public void setTranspose(boolean transpose) {
this.transpose = transpose;
}
/**
* 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.
*
* @param query the query.
*
* @throws SQLException if there is a problem executing the query.
*/
public void executeQuery(String query) throws SQLException {
executeQuery(this.connection, query);
}
/**
* 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.
*
* @param con the connection.
* @param query the query.
*
* @throws SQLException if there is a problem executing the query.
*/
public void executeQuery(Connection con, String query) throws SQLException {
Statement statement = null;
ResultSet resultSet = null;
try {
statement = con.createStatement();
resultSet = statement.executeQuery(query);
ResultSetMetaData metaData = resultSet.getMetaData();
int columnCount = metaData.getColumnCount();
if (columnCount < 2) {
throw new SQLException(
"JDBCCategoryDataset.executeQuery() : insufficient columns "
+ "returned from the database.");
}
// Remove any previous old data
int i = getRowCount();
while (--i >= 0) {
removeRow(i);
}
while (resultSet.next()) {
// first column contains the row key...
Comparable rowKey = resultSet.getString(1);
for (int column = 2; column <= columnCount; column++) {
Comparable columnKey = metaData.getColumnName(column);
int columnType = metaData.getColumnType(column);
switch (columnType) {
case Types.TINYINT:
case Types.SMALLINT:
case Types.INTEGER:
case Types.BIGINT:
case Types.FLOAT:
case Types.DOUBLE:
case Types.DECIMAL:
case Types.NUMERIC:
case Types.REAL: {
Number value = (Number) resultSet.getObject(column);
if (this.transpose) {
setValue(value, columnKey, rowKey);
}
else {
setValue(value, rowKey, columnKey);
}
break;
}
case Types.DATE:
case Types.TIME:
case Types.TIMESTAMP: {
Date date = (Date) resultSet.getObject(column);
Number value = date.getTime();
if (this.transpose) {
setValue(value, columnKey, rowKey);
}
else {
setValue(value, rowKey, columnKey);
}
break;
}
case Types.CHAR:
case Types.VARCHAR:
case Types.LONGVARCHAR: {
String string
= (String) resultSet.getObject(column);
try {
Number value = Double.valueOf(string);
if (this.transpose) {
setValue(value, columnKey, rowKey);
}
else {
setValue(value, rowKey, columnKey);
}
}
catch (NumberFormatException e) {
// suppress (value defaults to null)
}
break;
}
default:
// not a value, can't use it (defaults to null)
break;
}
}
}
fireDatasetChanged();
}
finally {
if (resultSet != null) {
try {
resultSet.close();
}
catch (Exception e) {
// report this?
}
}
if (statement != null) {
try {
statement.close();
}
catch (Exception e) {
// report this?
}
}
}
}
}