Getting started

Simple example to get started with Simple-persistence.

The following jars are required on the classpath:

• prevayler-2.x.jar]
• simple-persistence-x.x.jar

simple-persistence-0.3.zip

Create a model object:

• implement Persistent
• implement both methods getId() and clone()
• make sure it has a serialVersionUID

import nl.astraeus.persistence.Persistent

public class Comment implements Persistent<Long> {
    public final static long serialVersionUID = -9038882251579382910L;

    private long id;
    private long date = System.currentTimeMillis();
    private String description = "";

    public Comment() { }

    public Comment(String description) {
        this.id = IdGenerator.nextId();
        this.description = description;
    }

    public Long getId() {
      return id;
    }

    public Comment clone() throws CloneNotSupportedException {
        return (Comment)super.clone();
    }
}

Create a Dao object to work with it:

public class CommentDao extends PersistentDao<Long, Comment> {

}

To create and store a new Comment object: (we need the autocommit setting or a transaction but let's ignore that for now)

public class TestCreateComment {

    public static void main(String [] args) {
        System.setProperty(SimpleStore.AUTOCOMMIT, String.valueOf(true));

        Comment comment = new Comment("Some comment on something");

        CommentDao dao = new CommentDao();

        dao.store(comment);
  }
}

And that't it, your object is now persistent. Let's take a look at all comments:

public class TestShowComments {

    public static void main(String [] args) {
        CommentDao dao = new CommentDao();

        Collection<Comment> comments = dao.findAll();

        for (Comment comment : comments) {
            System.out.println("Comment: "+comment);
        }

        // find by id
        Comment comment = dao.find(1L);
    }
}

Next: References