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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2002-2009 Oracle. All rights reserved.
*
* $Id$
*/
package persist;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.HashSet;
import java.util.Set;
import com.sleepycat.db.DatabaseException;
import com.sleepycat.db.Environment;
import com.sleepycat.db.EnvironmentConfig;
import com.sleepycat.persist.EntityCursor;
import com.sleepycat.persist.EntityIndex;
import com.sleepycat.persist.EntityStore;
import com.sleepycat.persist.PrimaryIndex;
import com.sleepycat.persist.SecondaryIndex;
import com.sleepycat.persist.StoreConfig;
import com.sleepycat.persist.model.Entity;
import com.sleepycat.persist.model.Persistent;
import com.sleepycat.persist.model.PrimaryKey;
import com.sleepycat.persist.model.SecondaryKey;
import static com.sleepycat.persist.model.DeleteAction.NULLIFY;
import static com.sleepycat.persist.model.Relationship.ONE_TO_ONE;
import static com.sleepycat.persist.model.Relationship.ONE_TO_MANY;
import static com.sleepycat.persist.model.Relationship.MANY_TO_ONE;
import static com.sleepycat.persist.model.Relationship.MANY_TO_MANY;
public class PersonExample {
/* An entity class. */
@Entity
static class Person {
@PrimaryKey
String ssn;
String name;
Address address;
@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Person.class)
String parentSsn;
@SecondaryKey(relate=ONE_TO_MANY)
Set<String> emailAddresses = new HashSet<String>();
@SecondaryKey(relate=MANY_TO_MANY,
relatedEntity=Employer.class,
onRelatedEntityDelete=NULLIFY)
Set<Long> employerIds = new HashSet<Long>();
Person(String name, String ssn, String parentSsn) {
this.name = name;
this.ssn = ssn;
this.parentSsn = parentSsn;
}
private Person() {} // For deserialization
}
/* Another entity class. */
@Entity
static class Employer {
@PrimaryKey(sequence="ID")
long id;
@SecondaryKey(relate=ONE_TO_ONE)
String name;
Address address;
Employer(String name) {
this.name = name;
}
private Employer() {} // For deserialization
}
/* A persistent class used in other classes. */
@Persistent
static class Address {
String street;
String city;
String state;
int zipCode;
private Address() {} // For deserialization
}
/* The data accessor class for the entity model. */
static class PersonAccessor {
/* Person accessors */
PrimaryIndex<String,Person> personBySsn;
SecondaryIndex<String,String,Person> personByParentSsn;
SecondaryIndex<String,String,Person> personByEmailAddresses;
SecondaryIndex<Long,String,Person> personByEmployerIds;
/* Employer accessors */
PrimaryIndex<Long,Employer> employerById;
SecondaryIndex<String,Long,Employer> employerByName;
/* Opens all primary and secondary indices. */
public PersonAccessor(EntityStore store)
throws DatabaseException {
personBySsn = store.getPrimaryIndex(
String.class, Person.class);
personByParentSsn = store.getSecondaryIndex(
personBySsn, String.class, "parentSsn");
personByEmailAddresses = store.getSecondaryIndex(
personBySsn, String.class, "emailAddresses");
personByEmployerIds = store.getSecondaryIndex(
personBySsn, Long.class, "employerIds");
employerById = store.getPrimaryIndex(
Long.class, Employer.class);
employerByName = store.getSecondaryIndex(
employerById, String.class, "name");
}
}
public static void main(String[] args)
throws DatabaseException, FileNotFoundException {
if (args.length != 2 || !"-h".equals(args[0])) {
System.err.println
("Usage: java " + PersonExample.class.getName() +
" -h <envHome>");
System.exit(2);
}
PersonExample example = new PersonExample(new File(args[1]));
example.run();
example.close();
}
private Environment env;
private EntityStore store;
private PersonAccessor dao;
private PersonExample(File envHome)
throws DatabaseException, FileNotFoundException {
/* Open a transactional Berkeley DB engine environment. */
EnvironmentConfig envConfig = new EnvironmentConfig();
envConfig.setAllowCreate(true);
envConfig.setTransactional(true);
envConfig.setInitializeCache(true);
envConfig.setInitializeLocking(true);
env = new Environment(envHome, envConfig);
/* Open a transactional entity store. */
StoreConfig storeConfig = new StoreConfig();
storeConfig.setAllowCreate(true);
storeConfig.setTransactional(true);
store = new EntityStore(env, "PersonStore", storeConfig);
/* Initialize the data access object. */
dao = new PersonAccessor(store);
}
private void run()
throws DatabaseException {
/*
* Add a parent and two children using the Person primary index.
* Specifying a non-null parentSsn adds the child Person to the
* sub-index of children for that parent key.
*/
dao.personBySsn.put
(new Person("Bob Smith", "111-11-1111", null));
dao.personBySsn.put
(new Person("Mary Smith", "333-33-3333", "111-11-1111"));
dao.personBySsn.put
(new Person("Jack Smith", "222-22-2222", "111-11-1111"));
/* Print the children of a parent using a sub-index and a cursor. */
EntityCursor<Person> children =
dao.personByParentSsn.subIndex("111-11-1111").entities();
try {
for (Person child : children) {
System.out.println(child.ssn + ' ' + child.name);
}
} finally {
children.close();
}
/* Get Bob by primary key using the primary index. */
Person bob = dao.personBySsn.get("111-11-1111");
assert bob != null;
/*
* Create two employers if they do not already exist. Their primary
* keys are assigned from a sequence.
*/
Employer gizmoInc = dao.employerByName.get("Gizmo Inc");
if (gizmoInc == null) {
gizmoInc = new Employer("Gizmo Inc");
dao.employerById.put(gizmoInc);
}
Employer gadgetInc = dao.employerByName.get("Gadget Inc");
if (gadgetInc == null) {
gadgetInc = new Employer("Gadget Inc");
dao.employerById.put(gadgetInc);
}
/* Bob has two jobs and two email addresses. */
bob.employerIds.add(gizmoInc.id);
bob.employerIds.add(gadgetInc.id);
bob.emailAddresses.add("bob@bob.com");
bob.emailAddresses.add("bob@gmail.com");
/* Update Bob's record. */
dao.personBySsn.put(bob);
/* Bob can now be found by both email addresses. */
bob = dao.personByEmailAddresses.get("bob@bob.com");
assert bob != null;
bob = dao.personByEmailAddresses.get("bob@gmail.com");
assert bob != null;
/* Bob can also be found as an employee of both employers. */
EntityIndex<String,Person> employees;
employees = dao.personByEmployerIds.subIndex(gizmoInc.id);
assert employees.contains("111-11-1111");
employees = dao.personByEmployerIds.subIndex(gadgetInc.id);
assert employees.contains("111-11-1111");
/*
* When an employer is deleted, the onRelatedEntityDelete=NULLIFY for
* the employerIds key causes the deleted ID to be removed from Bob's
* employerIds.
*/
dao.employerById.delete(gizmoInc.id);
bob = dao.personBySsn.get("111-11-1111");
assert bob != null;
assert !bob.employerIds.contains(gizmoInc.id);
}
private void close()
throws DatabaseException {
store.close();
env.close();
}
}
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