1 /*-
2  * See the file LICENSE for redistribution information.
3  *
4  * Copyright (c) 2002, 2013 Oracle and/or its affiliates.  All rights reserved.
5  *
6  * $Id$
7  */
8 
9 package collections.ship.sentity;
10 
11 import java.io.FileNotFoundException;
12 import java.util.Iterator;
13 import java.util.Set;
14 
15 import com.sleepycat.collections.StoredIterator;
16 import com.sleepycat.collections.TransactionRunner;
17 import com.sleepycat.collections.TransactionWorker;
18 import com.sleepycat.db.DatabaseException;
19 
20 /**
21  * Sample is the main entry point for the sample program and may be run as
22  * follows:
23  *
24  * <pre>
25  * java collections.ship.sentity.Sample
26  *      [-h <home-directory> ]
27  * </pre>
28  *
29  * <p> The default for the home directory is ./tmp -- the tmp subdirectory of
30  * the current directory where the sample is run. To specify a different home
31  * directory, use the -home option. The home directory must exist before
32  * running the sample.  To recreate the sample database from scratch, delete
33  * all files in the home directory before running the sample. </p>
34  *
35  * @author Mark Hayes
36  */
37 public class Sample {
38 
39     private SampleDatabase db;
40     private SampleViews views;
41 
42     /**
43      * Run the sample program.
44      */
main(String[] args)45     public static void main(String[] args) {
46 
47         System.out.println("\nRunning sample: " + Sample.class);
48 
49         // Parse the command line arguments.
50         //
51         String homeDir = "./tmp";
52         for (int i = 0; i < args.length; i += 1) {
53             if (args[i].equals("-h") && i < args.length - 1) {
54                 i += 1;
55                 homeDir = args[i];
56             } else {
57                 System.err.println("Usage:\n java " + Sample.class.getName() +
58 				   "\n  [-h <home-directory>]");
59                 System.exit(2);
60             }
61         }
62 
63         // Run the sample.
64         //
65         Sample sample = null;
66         try {
67             sample = new Sample(homeDir);
68             sample.run();
69         } catch (Exception e) {
70             // If an exception reaches this point, the last transaction did not
71             // complete.  If the exception is RunRecoveryException, follow
72             // the Berkeley DB recovery procedures before running again.
73             e.printStackTrace();
74         } finally {
75             if (sample != null) {
76                 try {
77                     // Always attempt to close the database cleanly.
78                     sample.close();
79                 } catch (Exception e) {
80                     System.err.println("Exception during database close:");
81                     e.printStackTrace();
82                 }
83             }
84         }
85     }
86 
87     /**
88      * Open the database and views.
89      */
Sample(String homeDir)90     private Sample(String homeDir)
91         throws DatabaseException, FileNotFoundException {
92 
93         db = new SampleDatabase(homeDir);
94         views = new SampleViews(db);
95     }
96 
97     /**
98      * Close the database cleanly.
99      */
close()100     private void close()
101         throws DatabaseException {
102 
103         db.close();
104     }
105 
106     /**
107      * Run two transactions to populate and print the database.  A
108      * TransactionRunner is used to ensure consistent handling of transactions,
109      * including deadlock retries.  But the best transaction handling mechanism
110      * to use depends on the application.
111      */
run()112     private void run()
113         throws Exception {
114 
115         TransactionRunner runner = new TransactionRunner(db.getEnvironment());
116         runner.run(new PopulateDatabase());
117         runner.run(new PrintDatabase());
118     }
119 
120     /**
121      * Populate the database in a single transaction.
122      */
123     private class PopulateDatabase implements TransactionWorker {
124 
doWork()125         public void doWork()
126             throws Exception {
127             addSuppliers();
128             addParts();
129             addShipments();
130         }
131     }
132 
133     /**
134      * Print the database in a single transaction.  All entities are printed
135      * and the indices are used to print the entities for certain keys.
136      *
137      * <p> Note the use of special iterator() methods.  These are used here
138      * with indices to find the shipments for certain keys.  For details on
139      * database iterators see {@link StoredIterator}. </p>
140      */
141     private class PrintDatabase implements TransactionWorker {
142 
doWork()143         public void doWork()
144             throws Exception {
145             printValues("Parts",
146 			views.getPartSet().iterator());
147             printValues("Suppliers",
148 			views.getSupplierSet().iterator());
149             printValues("Suppliers for City Paris",
150                         views.getSupplierByCityMap().duplicates(
151                                             "Paris").iterator());
152             printValues("Shipments",
153 			views.getShipmentSet().iterator());
154             printValues("Shipments for Part P1",
155                         views.getShipmentByPartMap().duplicates(
156                                             new PartKey("P1")).iterator());
157             printValues("Shipments for Supplier S1",
158                         views.getShipmentBySupplierMap().duplicates(
159                                             new SupplierKey("S1")).iterator());
160         }
161     }
162 
163     /**
164      * Populate the part entities in the database.  If the part set is not
165      * empty, assume that this has already been done.
166      */
addParts()167     private void addParts() {
168 
169         Set parts = views.getPartSet();
170         if (parts.isEmpty()) {
171             System.out.println("Adding Parts");
172             parts.add(new Part("P1", "Nut", "Red",
173 			       new Weight(12.0, Weight.GRAMS), "London"));
174             parts.add(new Part("P2", "Bolt", "Green",
175 			       new Weight(17.0, Weight.GRAMS), "Paris"));
176             parts.add(new Part("P3", "Screw", "Blue",
177 			       new Weight(17.0, Weight.GRAMS), "Rome"));
178             parts.add(new Part("P4", "Screw", "Red",
179 			       new Weight(14.0, Weight.GRAMS), "London"));
180             parts.add(new Part("P5", "Cam", "Blue",
181 			       new Weight(12.0, Weight.GRAMS), "Paris"));
182             parts.add(new Part("P6", "Cog", "Red",
183 			       new Weight(19.0, Weight.GRAMS), "London"));
184         }
185     }
186 
187     /**
188      * Populate the supplier entities in the database.  If the supplier set is
189      * not empty, assume that this has already been done.
190      */
addSuppliers()191     private void addSuppliers() {
192 
193         Set suppliers = views.getSupplierSet();
194         if (suppliers.isEmpty()) {
195             System.out.println("Adding Suppliers");
196             suppliers.add(new Supplier("S1", "Smith", 20, "London"));
197             suppliers.add(new Supplier("S2", "Jones", 10, "Paris"));
198             suppliers.add(new Supplier("S3", "Blake", 30, "Paris"));
199             suppliers.add(new Supplier("S4", "Clark", 20, "London"));
200             suppliers.add(new Supplier("S5", "Adams", 30, "Athens"));
201         }
202     }
203 
204     /**
205      * Populate the shipment entities in the database.  If the shipment set
206      * is not empty, assume that this has already been done.
207      */
addShipments()208     private void addShipments() {
209 
210         Set shipments = views.getShipmentSet();
211         if (shipments.isEmpty()) {
212             System.out.println("Adding Shipments");
213             shipments.add(new Shipment("P1", "S1", 300));
214             shipments.add(new Shipment("P2", "S1", 200));
215             shipments.add(new Shipment("P3", "S1", 400));
216             shipments.add(new Shipment("P4", "S1", 200));
217             shipments.add(new Shipment("P5", "S1", 100));
218             shipments.add(new Shipment("P6", "S1", 100));
219             shipments.add(new Shipment("P1", "S2", 300));
220             shipments.add(new Shipment("P2", "S2", 400));
221             shipments.add(new Shipment("P2", "S3", 200));
222             shipments.add(new Shipment("P2", "S4", 200));
223             shipments.add(new Shipment("P4", "S4", 300));
224             shipments.add(new Shipment("P5", "S4", 400));
225         }
226     }
227 
228     /**
229      * Print the objects returned by an iterator of entity value objects.
230      *
231      * <p><b> IMPORTANT: All database iterators must be closed to avoid
232      * serious database problems.  If the iterator is not closed, the
233      * underlying Berkeley DB cursor is not closed either. </b></p>
234      */
printValues(String label, Iterator iterator)235     private void printValues(String label, Iterator iterator) {
236 
237         System.out.println("\n--- " + label + " ---");
238         try {
239             while (iterator.hasNext()) {
240                 System.out.println(iterator.next().toString());
241             }
242         } finally {
243             // IMPORTANT: Use StoredIterator to close all database
244             // iterators.  If java.util.Iterator is in hand, you can safely
245             // close it by calling StoredIterator.close(Iterator).
246             StoredIterator.close(iterator);
247         }
248     }
249 }
250