/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2002-2005
* Sleepycat Software. All rights reserved.
*
* $Id: Sample.java,v 1.13 2005/06/09 17:19:30 mark Exp $
*/
package collections.ship.basic;
import java.io.FileNotFoundException;
import java.util.Iterator;
import java.util.Map;
import com.sleepycat.collections.StoredIterator;
import com.sleepycat.collections.TransactionRunner;
import com.sleepycat.collections.TransactionWorker;
import com.sleepycat.je.DatabaseException;
/**
* Sample is the main entry point for the sample program and may be run as
* follows:
*
* <pre>
* java collections.ship.basic.Sample
* [-h <home-directory> ]
* </pre>
*
* <p> The default for the home directory is ./tmp -- the tmp subdirectory of
* the current directory where the sample is run. The home directory must exist
* before running the sample. To recreate the sample database from scratch,
* delete all files in the home directory before running the sample. </p>
*
* @author Mark Hayes
*/
public class Sample {
private SampleDatabase db;
private SampleViews views;
/**
* Run the sample program.
*/
public static void main(String[] args) {
System.out.println("\nRunning sample: " + Sample.class);
// Parse the command line arguments.
//
String homeDir = "./tmp";
for (int i = 0; i < args.length; i += 1) {
if (args[i].equals("-h") && i < args.length - 1) {
i += 1;
homeDir = args[i];
} else {
System.err.println("Usage:\n java " + Sample.class.getName() +
"\n [-h <home-directory>]");
System.exit(2);
}
}
// Run the sample.
//
Sample sample = null;
try {
sample = new Sample(homeDir);
sample.run();
} catch (Exception e) {
// If an exception reaches this point, the last transaction did not
// complete. If the exception is RunRecoveryException, follow
// the Berkeley DB recovery procedures before running again.
e.printStackTrace();
} finally {
if (sample != null) {
try {
// Always attempt to close the database cleanly.
sample.close();
} catch (Exception e) {
System.err.println("Exception during database close:");
e.printStackTrace();
}
}
}
}
/**
* Open the database and views.
*/
private Sample(String homeDir)
throws DatabaseException, FileNotFoundException {
db = new SampleDatabase(homeDir);
views = new SampleViews(db);
}
/**
* Close the database cleanly.
*/
private void close()
throws DatabaseException {
db.close();
}
/**
* Run two transactions to populate and print the database. A
* TransactionRunner is used to ensure consistent handling of transactions,
* including deadlock retries. But the best transaction handling mechanism
* to use depends on the application.
*/
private void run()
throws Exception {
TransactionRunner runner = new TransactionRunner(db.getEnvironment());
runner.run(new PopulateDatabase());
runner.run(new PrintDatabase());
}
/**
* Populate the database in a single transaction.
*/
private class PopulateDatabase implements TransactionWorker {
public void doWork()
throws Exception {
addSuppliers();
addParts();
addShipments();
}
}
/**
* Print the database in a single transaction. All entities are printed.
*/
private class PrintDatabase implements TransactionWorker {
public void doWork()
throws Exception {
printEntries("Parts",
views.getPartEntrySet().iterator());
printEntries("Suppliers",
views.getSupplierEntrySet().iterator());
printEntries("Shipments",
views.getShipmentEntrySet().iterator());
}
}
/**
* Populate the part entities in the database. If the part map is not
* empty, assume that this has already been done.
*/
private void addParts() {
Map parts = views.getPartMap();
if (parts.isEmpty()) {
System.out.println("Adding Parts");
parts.put(new PartKey("P1"),
new PartData("Nut", "Red",
new Weight(12.0, Weight.GRAMS),
"London"));
parts.put(new PartKey("P2"),
new PartData("Bolt", "Green",
new Weight(17.0, Weight.GRAMS),
"Paris"));
parts.put(new PartKey("P3"),
new PartData("Screw", "Blue",
new Weight(17.0, Weight.GRAMS),
"Rome"));
parts.put(new PartKey("P4"),
new PartData("Screw", "Red",
new Weight(14.0, Weight.GRAMS),
"London"));
parts.put(new PartKey("P5"),
new PartData("Cam", "Blue",
new Weight(12.0, Weight.GRAMS),
"Paris"));
parts.put(new PartKey("P6"),
new PartData("Cog", "Red",
new Weight(19.0, Weight.GRAMS),
"London"));
}
}
/**
* Populate the supplier entities in the database. If the supplier map is
* not empty, assume that this has already been done.
*/
private void addSuppliers() {
Map suppliers = views.getSupplierMap();
if (suppliers.isEmpty()) {
System.out.println("Adding Suppliers");
suppliers.put(new SupplierKey("S1"),
new SupplierData("Smith", 20, "London"));
suppliers.put(new SupplierKey("S2"),
new SupplierData("Jones", 10, "Paris"));
suppliers.put(new SupplierKey("S3"),
new SupplierData("Blake", 30, "Paris"));
suppliers.put(new SupplierKey("S4"),
new SupplierData("Clark", 20, "London"));
suppliers.put(new SupplierKey("S5"),
new SupplierData("Adams", 30, "Athens"));
}
}
/**
* Populate the shipment entities in the database. If the shipment map
* is not empty, assume that this has already been done.
*/
private void addShipments() {
Map shipments = views.getShipmentMap();
if (shipments.isEmpty()) {
System.out.println("Adding Shipments");
shipments.put(new ShipmentKey("P1", "S1"),
new ShipmentData(300));
shipments.put(new ShipmentKey("P2", "S1"),
new ShipmentData(200));
shipments.put(new ShipmentKey("P3", "S1"),
new ShipmentData(400));
shipments.put(new ShipmentKey("P4", "S1"),
new ShipmentData(200));
shipments.put(new ShipmentKey("P5", "S1"),
new ShipmentData(100));
shipments.put(new ShipmentKey("P6", "S1"),
new ShipmentData(100));
shipments.put(new ShipmentKey("P1", "S2"),
new ShipmentData(300));
shipments.put(new ShipmentKey("P2", "S2"),
new ShipmentData(400));
shipments.put(new ShipmentKey("P2", "S3"),
new ShipmentData(200));
shipments.put(new ShipmentKey("P2", "S4"),
new ShipmentData(200));
shipments.put(new ShipmentKey("P4", "S4"),
new ShipmentData(300));
shipments.put(new ShipmentKey("P5", "S4"),
new ShipmentData(400));
}
}
/**
* Print the key/value objects returned by an iterator of Map.Entry
* objects.
*
* <p><b> IMPORTANT: All database iterators must be closed to avoid
* serious database problems. If the iterator is not closed, the
* underlying Berkeley DB cursor is not closed either. </b></p>
*/
private void printEntries(String label, Iterator iterator) {
System.out.println("\n--- " + label + " ---");
try {
while (iterator.hasNext()) {
Map.Entry entry = (Map.Entry) iterator.next();
System.out.println(entry.getKey().toString());
System.out.println(entry.getValue().toString());
}
} finally {
// IMPORTANT: Use StoredIterator to close all database
// iterators. If java.util.Iterator is in hand, you can safely
// close it by calling StoredIterator.close(Iterator).
StoredIterator.close(iterator);
}
}
}