|
The objective of our sample application is to store messages in a database and to retrieve them for display. The application has a simple persistent class, Message, which represents these printable messages. Our Message class is shown in example below:
In this example Our Message class has three attributes: the identifier attribute, the text of the message, and a reference to another Message. The identifier attribute allows the application to access the database identity—the primary key value—of a persistent object. If two instances of Message have the same identifier value, they represent the same row in the database. We’ve chosen Long for the type of our identifier attribute, but this isn’t a requirement. Hibernate allows virtually anything for the identifier type.
package hello;
public class Message {
private Long id;
private String text;
private Message nextMessage;
private Message() {}
public Message(String text) {
this.text = text;
}
public Long getId() {
return id;
}
private void setId(Long id) {
this.id = id;
}
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public Message getNextMessage() {
return nextMessage;
}
public void setNextMessage(Message nextMessage) {
this.nextMessage = nextMessage;
}
}
|
|
