public class InitConfig {
private final SessionFactory sessionFactory;
private final NodeManager nodeManager;
public void run() {
final Configuration config = new Configuration("NewConfiguration", new HashSet<Node> ());
for(String name : lotsOfNames) {
//Lots of these queries run slowly
final Node node = this.nodeManager.getNode(name);
config.addNode(node);
}
this.sessionFactory.getCurrentSession().save(config);
}
}
相关的DAO(NodeManager)和慢速查询实体(Node)看起来像这样:
public class NodeManager {
private final SessionFactory sessionFactory;
public Node getNode(String name) {
final Session db = this.sessionFactory.getCurrentSession();
final Query query = db.createQuery("from NODE where NAME = :name");
query.setString("name", name);
return (Node)query.uniqueResult();
}
}
@Entity(name="NODE")
public class Node {
@GeneratedValue(strategy=GenerationType.TABLE)
@Id @Column(name="ID")
private Long id;
private @Column(name="NAME", nullable=false, unique=true) String name;
//Other properties and associations...
}
@Entity(name="CONFIGURATION")
public class Configuration {
@Id @GeneratedValue @Column(name="ID")
private Long id;
private @Column(name="NAME", nullable=false, unique=true) String name;
@ManyToMany
@JoinTable(
name="CONFIGURATION_NODE",
joinColumns=@JoinColumn(name="CONFIGURATION_ID", nullable=false),
inverseJoinColumns=@JoinColumn(name="NODE_ID", nullable=false))
private Set<Node> nodes = new HashSet<Node> ();
public void addNode(Node node) {
this.nodes.add(node);
}
}
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Hibernate的二级缓存是否适用于此,如果适用,我该如何配置它?
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如果没有,还有其他Hibernate功能可以在这里使用吗?