Some helper classes to make a database connection. These examples were written in the context of the book "iText in Action - Second Edition".
DatabaseConnection.java
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/*
* This class is part of the book "iText in Action - 2nd Edition"
* written by Bruno Lowagie (ISBN: 9781935182610)
* For more info, go to: http://itextpdf.com/examples/
* This example only works with the AGPL version of iText.
*/
package com.lowagie.database;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
/**
* This is a helper class to access the database
* that comes with the book samples.
*/
public abstract class DatabaseConnection {
/** our connection to the db. */
protected Connection connection;
/**
* Closes the connection to the database.
*/
public void close() throws SQLException {
connection.close();
}
/**
* Creates a statement.
* @return a statement
* @throws SQLException
*/
public Statement createStatement() throws SQLException {
return connection.createStatement();
}
/**
* Creates a prepated statement using a query.
* @param query the query that will be used to create
* a prepared statement.
* @return a statement
* @throws SQLException
*/
public PreparedStatement createPreparedStatement(String query)
throws SQLException {
return connection.prepareStatement(query);
}
/**
* Performs an update in the database.
* @param expression an SQL expression
* (CREATE, DROP, INSERT, UPDATE)
*/
public void update(String expression) throws SQLException {
Statement st = createStatement();
int i = st.executeUpdate(expression);
st.close();
if (i == -1) {
throw new SQLException("db error : " + expression);
}
}
}
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/*
* This class is part of the book "iText in Action - 2nd Edition"
* written by Bruno Lowagie (ISBN: 9781935182610)
* For more info, go to: http://itextpdf.com/examples/
* This example only works with the AGPL version of iText.
*/
package com.lowagie.database;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
/**
* This is a helper class to access an hsqldb database.
* The database scripts are supposed to be present in directory:
* resources/db
*/
public class HsqldbConnection extends DatabaseConnection {
/**
* Creates the connection.
* @param db_file_name_prefix the database name,
* which is the prefix of the database file
* @throws SQLException
*/
public HsqldbConnection(String db_file_name_prefix)
throws SQLException {
try {
Class.forName("org.hsqldb.jdbcDriver");
} catch (ClassNotFoundException e) {
throw new SQLException("HSQLDB database driver not found");
}
connection = DriverManager.getConnection(
"jdbc:hsqldb:resources/db/" + db_file_name_prefix, "SA", "");
}
/**
* Shuts down the database and closes the connection.
*/
public void close() throws SQLException {
Statement st = createStatement();
st.execute("SHUTDOWN");
super.close();
}
}
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/*
* This class is part of the book "iText in Action - 2nd Edition"
* written by Bruno Lowagie (ISBN: 9781935182610)
* For more info, go to: http://itextpdf.com/examples/
* This example only works with the AGPL version of iText.
*/
package com.lowagie.database;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.sql.SQLException;
/**
* Creates the hsqldatabase using SQL scripts containing
* CREATE statements with the table definitions, and
* INSERT statements with the data.
*/
public class CreateHsqldbTables {
/**
* Imports a number of SQL scripts into an HSQLDB database.
* @param args no arguments needed
* @throws SQLException
* @throws IOException
* @throws UnsupportedEncodingException
*/
public static void main(String[] args)
throws SQLException, UnsupportedEncodingException, IOException {
DatabaseConnection conn = new HsqldbConnection("filmfestival");
BufferedReader in;
String line;
conn.update("SET IGNORECASE TRUE");
in = new BufferedReader(
new FileReader("resources/scripts/filmfestival_hsqldb.sql"));
while( (line = in.readLine()) != null) {
conn.update(line);
}
in = new BufferedReader(
new FileReader("resources/scripts/filmfestival.sql"));
while( (line = in.readLine()) != null) {
conn.update(line);
}
conn.close();
}
}
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/*
* This class is part of the book "iText in Action - 2nd Edition"
* written by Bruno Lowagie (ISBN: 9781935182610)
* For more info, go to: http://itextpdf.com/examples/
* This example only works with the AGPL version of iText.
*/
package com.lowagie.database;
import java.io.FileInputStream;
import java.io.IOException;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
/**
* This is a helper class to access a mySql database.
* The username and password of the database are supposed to be present
* in a properties file mysql.props (in the working directory)
*/
public class MySqlConnection extends DatabaseConnection {
/**
* Creates the connection.
* @param db_file_name_prefix the database name,
* which is the prefix of the database file
* @throws SQLException
*/
public MySqlConnection(String database) throws SQLException {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
throw new SQLException("mySql database driver not found");
}
Properties credentials = new Properties();
try {
credentials.load(new FileInputStream("mysql.props"));
} catch (IOException e) {
throw new SQLException("Can't read mysql.props.");
}
connection = DriverManager.getConnection(
"jdbc:mysql://localhost/" + database,
credentials.getProperty("username"),
credentials.getProperty("password"));
}
}