public class

HsqlMaxValueIncrementer

extends AbstractColumnMaxValueIncrementer
java.lang.Object
   ↳ org.springframework.jdbc.support.incrementer.AbstractDataFieldMaxValueIncrementer
     ↳ org.springframework.jdbc.support.incrementer.AbstractColumnMaxValueIncrementer
       ↳ org.springframework.jdbc.support.incrementer.HsqlMaxValueIncrementer

Class Overview

DataFieldMaxValueIncrementer that increments the maximum value of a given HSQL table with the equivalent of an auto-increment column. Note: If you use this class, your HSQL key column should NOT be auto-increment, as the sequence table does the job.

The sequence is kept in a table. There should be one sequence table per table that needs an auto-generated key.

Example:

create table tab (id int not null primary key, text varchar(100));
 create table tab_sequence (value identity);
 insert into tab_sequence values(0);
If "cacheSize" is set, the intermediate values are served without querying the database. If the server or your application is stopped or crashes or a transaction is rolled back, the unused values will never be served. The maximum hole size in numbering is consequently the value of cacheSize.

NOTE: HSQL now supports sequences and you should consider using them instead: HsqlSequenceMaxValueIncrementer

Summary

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Inherited Fields
From class org.springframework.jdbc.support.incrementer.AbstractDataFieldMaxValueIncrementer
Public Constructors
HsqlMaxValueIncrementer()
Default constructor for bean property style usage.
HsqlMaxValueIncrementer(DataSource dataSource, String incrementerName, String columnName)
Convenience constructor.
Protected Methods
synchronized long getNextKey()
Determine the next key to use, as a long.
[Expand]
Inherited Methods
From class org.springframework.jdbc.support.incrementer.AbstractColumnMaxValueIncrementer
From class org.springframework.jdbc.support.incrementer.AbstractDataFieldMaxValueIncrementer
From class java.lang.Object
From interface org.springframework.beans.factory.InitializingBean
From interface org.springframework.jdbc.support.incrementer.DataFieldMaxValueIncrementer

Public Constructors

public HsqlMaxValueIncrementer ()

Default constructor for bean property style usage.

public HsqlMaxValueIncrementer (DataSource dataSource, String incrementerName, String columnName)

Convenience constructor.

Parameters
dataSource the DataSource to use
incrementerName the name of the sequence/table to use
columnName the name of the column in the sequence table to use

Protected Methods

protected synchronized long getNextKey ()

Determine the next key to use, as a long.

Returns
  • the key to use as a long. It will eventually be converted later in another format by the public concrete methods of this class.