public static void viewTable(Connection con) throws SQLException {
Statement stmt = null;
String query = "select COF_NAME, SUP_ID, PRICE, SALES, TOTAL from COFFEES";
try {
stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(query);
while (rs.next()) {
String coffeeName = rs.getString("COF_NAME");
int supplierID = rs.getInt("SUP_ID");
float price = rs.getFloat("PRICE");
int sales = rs.getInt("SALES");
int total = rs.getInt("TOTAL");
System.out.println(
coffeeName + ", " + supplierID + ", " + price + ", " + sales + ", " + total);
}
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) {
stmt.close();
}
}
}
public void batchUpdate() throws SQLException {
Statement stmt = null;
try {
this.con.setAutoCommit(false);
stmt = this.con.createStatement();
stmt.addBatch("INSERT INTO COFFEES " + "VALUES('Amaretto', 49, 9.99, 0, 0)");
stmt.addBatch("INSERT INTO COFFEES " + "VALUES('Hazelnut', 49, 9.99, 0, 0)");
stmt.addBatch("INSERT INTO COFFEES " + "VALUES('Amaretto_decaf', 49, 10.99, 0, 0)");
stmt.addBatch("INSERT INTO COFFEES " + "VALUES('Hazelnut_decaf', 49, 10.99, 0, 0)");
int[] updateCounts = stmt.executeBatch();
this.con.commit();
} catch (BatchUpdateException b) {
JDBCTutorialUtilities.printBatchUpdateException(b);
} catch (SQLException ex) {
JDBCTutorialUtilities.printSQLException(ex);
} finally {
if (stmt != null) {
stmt.close();
}
this.con.setAutoCommit(true);
}
}
public void insertRow(String coffeeName, int supplierID, float price, int sales, int total)
throws SQLException {
Statement stmt = null;
try {
stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
ResultSet uprs = stmt.executeQuery("SELECT * FROM COFFEES");
uprs.moveToInsertRow();
uprs.updateString("COF_NAME", coffeeName);
uprs.updateInt("SUP_ID", supplierID);
uprs.updateFloat("PRICE", price);
uprs.updateInt("SALES", sales);
uprs.updateInt("TOTAL", total);
uprs.insertRow();
uprs.beforeFirst();
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) {
stmt.close();
}
}
}
public void updateCoffeeSales(HashMap<String, Integer> salesForWeek) throws SQLException {
PreparedStatement updateSales = null;
PreparedStatement updateTotal = null;
String updateString = "update COFFEES " + "set SALES = ? where COF_NAME = ?";
String updateStatement = "update COFFEES " + "set TOTAL = TOTAL + ? where COF_NAME = ?";
try {
con.setAutoCommit(false);
updateSales = con.prepareStatement(updateString);
updateTotal = con.prepareStatement(updateStatement);
for (Map.Entry<String, Integer> e : salesForWeek.entrySet()) {
updateSales.setInt(1, e.getValue().intValue());
updateSales.setString(2, e.getKey());
updateSales.executeUpdate();
updateTotal.setInt(1, e.getValue().intValue());
updateTotal.setString(2, e.getKey());
updateTotal.executeUpdate();
con.commit();
}
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
if (con != null) {
try {
System.err.print("Transaction is being rolled back");
con.rollback();
} catch (SQLException excep) {
JDBCTutorialUtilities.printSQLException(excep);
}
}
} finally {
if (updateSales != null) {
updateSales.close();
}
if (updateTotal != null) {
updateTotal.close();
}
con.setAutoCommit(true);
}
}
public void modifyPricesByPercentage(String coffeeName, float priceModifier, float maximumPrice)
throws SQLException {
con.setAutoCommit(false);
Statement getPrice = null;
Statement updatePrice = null;
ResultSet rs = null;
String query = "SELECT COF_NAME, PRICE FROM COFFEES " + "WHERE COF_NAME = '" + coffeeName + "'";
try {
Savepoint save1 = con.setSavepoint();
getPrice = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
updatePrice = con.createStatement();
if (!getPrice.execute(query)) {
System.out.println("Could not find entry for coffee named " + coffeeName);
} else {
rs = getPrice.getResultSet();
rs.first();
float oldPrice = rs.getFloat("PRICE");
float newPrice = oldPrice + (oldPrice * priceModifier);
System.out.println("Old price of " + coffeeName + " is " + oldPrice);
System.out.println("New price of " + coffeeName + " is " + newPrice);
System.out.println("Performing update...");
updatePrice.executeUpdate(
"UPDATE COFFEES SET PRICE = " + newPrice + " WHERE COF_NAME = '" + coffeeName + "'");
System.out.println("\nCOFFEES table after update:");
CoffeesTable.viewTable(con);
if (newPrice > maximumPrice) {
System.out.println(
"\nThe new price, "
+ newPrice
+ ", is greater than the maximum "
+ "price, "
+ maximumPrice
+ ". Rolling back the transaction...");
con.rollback(save1);
System.out.println("\nCOFFEES table after rollback:");
CoffeesTable.viewTable(con);
}
con.commit();
}
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (getPrice != null) {
getPrice.close();
}
if (updatePrice != null) {
updatePrice.close();
}
con.setAutoCommit(true);
}
}
public void dropTable() throws SQLException {
Statement stmt = null;
try {
stmt = con.createStatement();
if (this.dbms.equals("mysql")) {
stmt.executeUpdate("DROP TABLE IF EXISTS COFFEES");
} else if (this.dbms.equals("derby")) {
stmt.executeUpdate("DROP TABLE COFFEES");
}
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) {
stmt.close();
}
}
}
public void populateTable() throws SQLException {
Statement stmt = null;
try {
stmt = con.createStatement();
stmt.executeUpdate("insert into COFFEES " + "values('Colombian', 00101, 7.99, 0, 0)");
stmt.executeUpdate("insert into COFFEES " + "values('French_Roast', 00049, 8.99, 0, 0)");
stmt.executeUpdate("insert into COFFEES " + "values('Espresso', 00150, 9.99, 0, 0)");
stmt.executeUpdate("insert into COFFEES " + "values('Colombian_Decaf', 00101, 8.99, 0, 0)");
stmt.executeUpdate(
"insert into COFFEES " + "values('French_Roast_Decaf', 00049, 9.99, 0, 0)");
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) {
stmt.close();
}
}
}
public Set<String> getKeys() throws SQLException {
HashSet<String> keys = new HashSet<String>();
Statement stmt = null;
String query = "select COF_NAME from COFFEES";
try {
stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(query);
while (rs.next()) {
keys.add(rs.getString(1));
}
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) {
stmt.close();
}
}
return keys;
}
public void modifyPrices(float percentage) throws SQLException {
Statement stmt = null;
try {
stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
ResultSet uprs = stmt.executeQuery("SELECT * FROM COFFEES");
while (uprs.next()) {
float f = uprs.getFloat("PRICE");
uprs.updateFloat("PRICE", f * percentage);
uprs.updateRow();
}
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) {
stmt.close();
}
}
}
public void createTable() throws SQLException {
String createString =
"create table COFFEES "
+ "(COF_NAME varchar(32) NOT NULL, "
+ "SUP_ID int NOT NULL, "
+ "PRICE numeric(10,2) NOT NULL, "
+ "SALES integer NOT NULL, "
+ "TOTAL integer NOT NULL, "
+ "PRIMARY KEY (COF_NAME), "
+ "FOREIGN KEY (SUP_ID) REFERENCES SUPPLIERS (SUP_ID))";
Statement stmt = null;
try {
stmt = con.createStatement();
stmt.executeUpdate(createString);
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) {
stmt.close();
}
}
}
public static void main(String[] args) {
JDBCTutorialUtilities myJDBCTutorialUtilities;
Connection myConnection = null;
if (args[0] == null) {
System.err.println("Properties file not specified at command line");
return;
} else {
try {
myJDBCTutorialUtilities = new JDBCTutorialUtilities(args[0]);
} catch (Exception e) {
System.err.println("Problem reading properties file " + args[0]);
e.printStackTrace();
return;
}
}
try {
myConnection = myJDBCTutorialUtilities.getConnection();
// Java DB does not have an SQL create database command; it does require createDatabase
// JDBCTutorialUtilities.createDatabase(myConnection,
// myJDBCTutorialUtilities.dbName,
// myJDBCTutorialUtilities.dbms);
//
// JDBCTutorialUtilities.initializeTables(myConnection,
// myJDBCTutorialUtilities.dbName,
// myJDBCTutorialUtilities.dbms);
CoffeesTable myCoffeeTable =
new CoffeesTable(
myConnection, myJDBCTutorialUtilities.dbName, myJDBCTutorialUtilities.dbms);
System.out.println("\nContents of COFFEES table:");
CoffeesTable.viewTable(myConnection);
System.out.println("\nRaising coffee prices by 25%");
myCoffeeTable.modifyPrices(1.25f);
System.out.println("\nInserting a new row:");
myCoffeeTable.insertRow("Kona", 150, 10.99f, 0, 0);
CoffeesTable.viewTable(myConnection);
System.out.println("\nUpdating sales of coffee per week:");
HashMap<String, Integer> salesCoffeeWeek = new HashMap<String, Integer>();
salesCoffeeWeek.put("Colombian", 175);
salesCoffeeWeek.put("French_Roast", 150);
salesCoffeeWeek.put("Espresso", 60);
salesCoffeeWeek.put("Colombian_Decaf", 155);
salesCoffeeWeek.put("French_Roast_Decaf", 90);
myCoffeeTable.updateCoffeeSales(salesCoffeeWeek);
CoffeesTable.viewTable(myConnection);
System.out.println("\nModifying prices by percentage");
myCoffeeTable.modifyPricesByPercentage("Colombian", 0.10f, 9.00f);
System.out.println("\nCOFFEES table after modifying prices by percentage:");
myCoffeeTable.viewTable(myConnection);
System.out.println("\nPerforming batch updates; adding new coffees");
myCoffeeTable.batchUpdate();
myCoffeeTable.viewTable(myConnection);
// System.out.println("\nDropping Coffee and Suplliers table:");
//
// myCoffeeTable.dropTable();
// mySuppliersTable.dropTable();
} catch (SQLException e) {
JDBCTutorialUtilities.printSQLException(e);
} finally {
JDBCTutorialUtilities.closeConnection(myConnection);
}
}