|
/* From http://java.sun.com/docs/books/tutorial/index.html */
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class TransactionPairs {
public static void main(String args[]) {
String url = "jdbc:mySubprotocol:myDataSource";
Connection con = null;
Statement stmt;
PreparedStatement updateSales;
PreparedStatement updateTotal;
String updateString = "update COFFEES "
+ "set SALES = ? where COF_NAME like ?";
String updateStatement = "update COFFEES "
+ "set TOTAL = TOTAL + ? where COF_NAME like ?";
String query = "select COF_NAME, SALES, TOTAL from COFFEES";
try {
Class.forName("myDriver.ClassName");
} catch (java.lang.ClassNotFoundException e) {
System.err.print("ClassNotFoundException: ");
System.err.println(e.getMessage());
}
try {
con = DriverManager.getConnection(url, "myLogin", "myPassword");
updateSales = con.prepareStatement(updateString);
updateTotal = con.prepareStatement(updateStatement);
int[] salesForWeek = { 175, 150, 60, 155, 90 };
String[] coffees = { "Colombian", "French_Roast", "Espresso",
"Colombian_Decaf", "French_Roast_Decaf" };
int len = coffees.length;
con.setAutoCommit(false);
for (int i = 0; i < len; i++) {
updateSales.setInt(1, salesForWeek[i]);
updateSales.setString(2, coffees[i]);
updateSales.executeUpdate();
updateTotal.setInt(1, salesForWeek[i]);
updateTotal.setString(2, coffees[i]);
updateTotal.executeUpdate();
con.commit();
}
con.setAutoCommit(true);
updateSales.close();
updateTotal.close();
stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(query);
while (rs.next()) {
String c = rs.getString("COF_NAME");
int s = rs.getInt("SALES");
int t = rs.getInt("TOTAL");
System.out.println(c + " " + s + " " + t);
}
stmt.close();
con.close();
} catch (SQLException ex) {
System.err.println("SQLException: " + ex.getMessage());
if (con != null) {
try {
System.err.print("Transaction is being ");
System.err.println("rolled back");
con.rollback();
} catch (SQLException excep) {
System.err.print("SQLException: ");
System.err.println(excep.getMessage());
}
}
}
}
}
|
