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How to get the next value in a sequence with #GeneratedValue in spring-jpa

There is already some data available in table, where id being the primary key for me. So when i trying to invoke my spring jpa code to add values to the table i'm using #GeneratedValue for the primary key.
But this way is generating value which is already present in DB. so my application is throwing an exception.
Is there any way i can get the current value from the table and increment my primary key id wrt the previous value of ID present in the table
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE)
#Column(name = "id", updatable = false, nullable = false)
private int id;

Let's say your max id in DB currently is 500. Run this:
CREATE SEQUENCE seq_name_in_db START WITH 501;
And change to:
#Id
#SequenceGenerator(name = "some_seq", sequenceName = "seq_name_in_db")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "some_seq")
private int id;
UPDATE: (Solution to OP's comment)
While inserting directly, do this:
INSERT INTO some_table (id, ...) VALUES (seq_name_in_db.NEXTVAL, ...);

When You create the sequence, you can let it start with a certain value e.g.
CREATE SEQUENCE XX_SEQ
START WITH 100
INCREMENT BY 1 ;

creating sequence Id in hibernate

I wanted to generate sequence using hibernate tool ( pojo to sql). And definitely it works fine.
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "seqid-gen")
#SequenceGenerator(name = "seqid-gen", sequenceName = "RTDS_ADSINPUT_SEQ" )
#Column(name="id")
public Long getId() {
return id;
}
This code generates below sql
create sequence RTDS_ADSINPUT_SEQ;
The problem is I wanted to specify properties like
START WITH, INCREMENT BY, NOCACHE
and the final ddl script should be some thing like below
CREATE SEQUENCE RTDS_ADSINPUT_SEQ MINVALUE 1 MAXVALUE
999999999999999999 INCREMENT BY 1 START WITH 1 NOCACHE;
But as far I saw hibernate only support name, sequncename, allocationSize, initialvalue. My doubt is, if we use allocationSize = 1 & initialValue = 1 do we still need to mention "nocache". If so, do we have any kind of annotation for "nocache"?
Please advice me if I can include that properties as annotation in the pojo.

sequence use only oracle, postgreSQL, DB2, H2
I know two case.
(1)
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private int idx;
Auto_increment, sequence object -> strategy = GenerationType.AUTO
(2)
Your case.
Element Detail
public abstract String name (Required) A unique generator name that
can be referenced by one or more classes to be the generator for
primary key values.
public abstract String sequenceName (Optional) The name of the
database sequence object from which to obtain primary key values.
Defaults to a provider-chosen value. Default: hibernate_sequence
public abstract int initialValue (Optional) The value from which the
sequence object is to start generating. Default:1
public abstract int allocationSize (Optional) The amount to increment
by when allocating sequence numbers from the sequence. Default:50
DDL
create sequence RTDS_ADSINPUT_SEQ start with 1 increment by 1;
Entity
#Entity
#SequenceGenerator(
name = "seqid-gen",
sequenceName = "RTDS_ADSINPUT_SEQ"
initiaValue = 1, allocationSize = 1)
public class XXX {
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "seqid-gen")
private long id;
//getter, setter
}

As i know we do not have such annotation properties. But ideally, you should create the sequence using your own SQL query instead using the default one generated by hibernate. When the sequence existed in database, Hibernate will not generate one, you can also disable hibernate ddl generation.

We can generate sequence id using hibernate in below mentioned manner
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private int uniqueid;

Sequence used to increment and ID in Postgresql not called by hibernate

I added a sequence MAIL_ID_SEQ to an existing table in Postgresql :
CREATE SEQUENCE MAIL_ID_SEQ START WITH 1;
alter table MAIL alter column ID set default nextval('MAIL_ID_SEQ'::regclass);
alter SEQUENCE MAIL_ID_SEQ owned by MAIL.ID;
The ID exist inside a composite key MailId :
#Embeddable
public class MailId implements Serializable{
#Column(name = "ID")
private int id;
#Column(name = "YEAR")
private int year;
}
I want the ID to be auto_increment using the sequence I created.
The problem is that the value of the ID is always 0 when a new record is inserted from via Hibernate, but when I insert a value directly from the command line (inset into MAIL ..) in the MAIL table, the value of the ID is incremented.

You need to add annotations like this to the id field:
#SequenceGenerator(name = "mail_id_gen", sequenceName = "MAIL_ID_SEQ", allocationSize = 1)
#GeneratedValue(generator = "mail_id_gen")
The generator name must be different for each class. The allocationSize is completely optional, but setting it to 1 is a workaround to a bug in Hibernate 5.0 and 5.1 related to sequences not created by schema export. Another workaround for that bug is to set the hibernate.id.optimizer.pooled.preferred property to NONE in the persistence.xml like this:
<property name="hibernate.id.optimizer.pooled.preferred" value="NONE"/>
If this is not enough and it still tries to insert 0, change the field type from int to Integer and leave it's default to null.

Jpa 2.0 and Unique Constraints

I'm in a project which is based on Oracle DB and EclipseLink as EM implementation.
I got a table which has a standard id sequence generator, let's say:
#Id
#GeneratedValue(strategy = GenerationType.TABLE, generator = "INVOICE")
#TableGenerator(name = "INVOICE", allocationSize = 1, table = Constants.SEQUENCE_TABLE, schema = Constants.DATABASE_SCHEMA)
#Column(length = 40)
private String id;
I also got a unique numeric field. I've decided to create a special sequence for that field, and populate it through a trigger, which increments that numeric field on every insert, passing sequence "NextVal".
My question is: is it a good practice to take advantage of #Sequencegenerator and #TableGenerator annotation also for a field that is not an #Id for the same entity?
I'm not a trigger fan...so adding a thing like this from the hypothetical first snippet... i could manage whole entity with JPA standard Annotations:
#GeneratedValue(strategy = GenerationType.TABLE, generator = "UNIQUEFIELD")
#TableGenerator(name = "UNIQUEFIELD", allocationSize = 1)
#Column
private String uniqueValuesField;
Thanks!

JPA does not support sequences on non-id fields, so this isn't likely to work without relying or delving into your provider's native support.
You can always refresh the entity afterward if required to get the values set by triggers, but they are a common enough occurrence on legacy systems, so providers will have support of some form for triggers. EclipseLink has #ReturnInsert and #ReturnUpdate to allow getting the values back from triggers.

To mark a property as generated, use The Hibernate specific #Generated annotation.Properties marked as generated must additionally be non-insertable and non-updateable. Only #Version and #Basic types can be marked as generated.
http://docs.jboss.org/hibernate/orm/5.1/userguide/html_single/Hibernate_User_Guide.html#mapping-generated
never (the default)
the given property value is not generated within the database.
insert
the given property value is generated on insert, but is not regenerated on subsequent updates. Properties like creationTimestamp fall into this category.
always
the property value is generated both on insert and on update.
hope this can help you.

I think writing a trigger is a redundant action, and it will reduce the readability of the code.
There are three main types of ID generators provided in hibernate TABLE, SEQUENCE and IDENTITY.
here is a good read with examples by Vladmihalcea on the Sequence generator strategies provided.
Or else you can create your own sequence generator where I had to keep a unique id among two tables so I did this
#Id
#GenericGenerator(name = "sequence", strategy = "IdGenerator")
#GeneratedValue(generator = "sequence")
#Column(name = "ID", columnDefinition = "BIGINT")
and in the Id generator
Public class IdGenerator extends IncrementGenerator {
private static long nextVal = Long.MIN_VALUE;
private static Object idlock = new Object();
private static volatile String COLUMN_NAME = "id";
#Override
public Serializable generate(SessionImplementor session, Object obj) {
if (obj == null) {
throw new HibernateException("Null object passed");
}
synchronized (idlock) {
nextVal = //get the value according to your logic
}
return nextVal;
}
}

jpa hibernate: generation type sequence always inserts 0 into column

I'd like to generate a number like 16857 and have that unique for each entry (note, this column is NOT the primary key). I am using JPA, Hibernate and MySQL.
I tried this:
#Entity
#SequenceGenerator(name = "membernumber_sequence", initialValue = 10000, allocationSize = 1)
public class Member implements Model {
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "membernumber_sequence")
private int membernumber;
}
However, it always inserts 0 into the column. What am I doing wrong?

From the javadoc:
The GeneratedValue annotation may be applied to a primary key property or field of an entity or mapped superclass in conjunction with the Id annotation.
(emphasis mine)
Use a SQL query to get the next sequence value, and initialize the field explicitely.