Java Hibernate Cookbook

Creating an autogenerator column

Generally, we create a primary column with some autogenerated value. Hibernate allows us to create the same using code. Let's take a look at some methods to create a column with an autogenerated value.

How to do it…

We can create an autogenerated column in many ways, such as:

• Using a default generation strategy
• Using a sequence generator
• Using a table generator

Default generation strategy

To use a default strategy for autogeneration, we will use the @GeneratedValue annotation, as follows:

@Id
@GeneratedValue
private long id;

Using the preceding code, hibernate will create a column with an autoincremental value.

By default, hibernate uses the GenerationType.AUTO strategy if no strategy is supplied; so, @GeneratedValue is ...