(I already saw this problem somewhere online but a search query that depends on "100" as search term apparently isn't a promising one - so forgive me if this question has already been asked)
I've just started playing with berkeley DB in Java using its DPL feature. I created a Class "Client" which has the following primary key and sequence:
public class Client {
// primary key
@PrimaryKey(sequence="Client_ID")
private long id;
[...]
}
I'm adding a few sample Entities using the primary index:
clientById = store.getPrimaryIndex(Long.class, Client.class);
clientById.put(client);
The first time I'm starting the application, everything's ok. The sequence starts at 1 and increase by 1. The next time I start the application, it starts at 101 (stepping is still 1) instead of continnuing at 4 (I have 3 sample Entities). Is it possible to affect this behaviour somehow? I'd like to have an ongoing sequence.
Edit: This is my testcode:
public static void main(String[] args) {
test();
test();
}
public static void test() {
// create some test clients
Client c1 = new Client("Client 1", "Cli 1 street 1", null, "55411", "Bingen");
Client c2 = new Client("Client 2", "Cli 1 street 2", null, "55411", "Bingen");
Client c3 = new Client("Test Custoamer");
// create database
Store store = new Store();
ClientAccessor ca = new ClientAccessor(store.getStore());
ca.put(c1);
ca.put(c2);
ca.put(c3);
List<Client> clients = ca.getAll();
for (Client c : clients) {
System.out.println(c);
System.out.println("-------------------");
}
store.shutdown();
}
Store looks like this:
public class Store {
private File dbfile;
private Environment env;
private EntityStore store;
public Store() {
this(new File(System.getProperty("user.home"), "tmdb"));
}
public Store(File dbfile) {
this.dbfile = dbfile;
setup();
}
public void setup() {
EnvironmentConfig envConfig = new EnvironmentConfig();
envConfig.setAllowCreate(true);
envConfig.setTransactional(true);
env = new Environment(dbfile, envConfig);
StoreConfig storeConfig = new StoreConfig();
storeConfig.setAllowCreate(true);
storeConfig.setTransactional(true);
store = new EntityStore(env, "TimeManagement", storeConfig);
}
public void shutdown() {
store.close();
env.close();
}
public EntityStore getStore() {
return store;
}
}
ClientAccessor goes like this:
public class ClientAccessor {
private EntityStore store;
// primary index
PrimaryIndex<Long, Client> clientById;
public ClientAccessor(EntityStore store) {
this.store = store;
if (store == null)
throw new IllegalArgumentException("EntityStore can't be null!");
clientById = store.getPrimaryIndex(Long.class, Client.class);
}
public void put(Client c) {
clientById.put(c);
}
public List<Client> getAll() {
ArrayList<Client> clients = new ArrayList<Client>();
EntityCursor<Client> cursor = clientById.entities();
for (Client c : cursor) {
clients.add(c);
}
cursor.close();
return clients;
}
}
And the client looks like this:
@Entity
public class Client {
// primary key
@PrimaryKey(sequence="Client_ID")
private long id;
// secondary keys
@SecondaryKey(relate=Relationship.MANY_TO_ONE)
private String name;
@SecondaryKey(relate=Relationship.MANY_TO_ONE)
private String address1;
@SecondaryKey(relate=Relationship.MANY_TO_ONE)
private String address2;
@SecondaryKey(relate=Relationship.MANY_TO_ONE)
private String plz;
@SecondaryKey(relate=Relationship.MANY_TO_ONE)
private String city;
private Client(){}
// address is optional
public Client(String name) {
this(name, null, null, null, null);
}
public Client(String name, String address1, String address2, String plz, String city) {
this.setName(name);
this.setAddress1(address1);
this.setAddress2(address2);
this.setPlz(plz);
this.setCity(city);
}
@Override
public String toString() {
String str = "";
str += id + "\n";
str += name + "\n";
str += (address1 != null && ! address1.isEmpty()) ? address1 + "\n" : "";
str += (address2 != null && ! address2.isEmpty()) ? address2 + "\n" : "";
str += (plz != null && ! plz.isEmpty()) ? plz + " " : "";
str += (city != null &&! city.isEmpty()) ? city + "\n" : "";
return str;
}
// getters and setters
public long getId() {
return id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAddress1() {
return address1;
}
public void setAddress1(String address1) {
this.address1 = address1;
}
public String getAddress2() {
return address2;
}
public void setAddress2(String address2) {
this.address2 = address2;
}
public String getPlz() {
return plz;
}
public void setPlz(String plz) {
this.plz = plz;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
}
By default, the sequence caches 100 entries. To change this, add this code to the end of your Store.setup()
method:
SequenceConfig sequenceConfig = store.getSequenceConfig("Client_ID");
sequenceConfig.setCacheSize(1);
store.setSequenceConfig("Client_ID", sequenceConfig);