@Entity
@Table(name = "stock", catalog = "sample", uniqueConstraints = {
		@UniqueConstraint(columnNames = "STOCK_NAME"),
		@UniqueConstraint(columnNames = "STOCK_CODE") })
public class Stock implements java.io.Serializable {

	private Integer stockId;
	private String stockCode;
	private String stockName;
	private Set<StockDailyRecord> stockDailyRecords = new HashSet<StockDailyRecord>(0);

@Entity
@Table(name = "topic", catalog = "mkyongdb", uniqueConstraints = {
		@UniqueConstraint(columnNames = "topic_name") })
public class Topic {
	
	@Id
	@GeneratedValue(strategy = IDENTITY)
	@Column(name = "topic_id", unique = true, nullable = false)
	private Integer topicId;
	
	@Column(name = "topic_name", unique = true, nullable = false, length = 10)
	private String topicName;
	
	@OneToMany(fetch = FetchType.LAZY, mappedBy = "topic")
	private Set<ScoreRecord> records = new HashSet<ScoreRecord>(0);

Exception in thread "main" java.lang.StackOverflowError
	at java.util.HashMap$HashIterator.<init>(Unknown Source)
	at java.util.HashMap$KeyIterator.<init>(Unknown Source)
	at java.util.HashMap$KeyIterator.<init>(Unknown Source)
	at java.util.HashMap.newKeyIterator(Unknown Source)
	at java.util.HashMap$KeySet.iterator(Unknown Source)
	at java.util.HashSet.iterator(Unknown Source)
	at java.util.AbstractSet.hashCode(Unknown Source)
	at org.hibernate.collection.PersistentSet.hashCode(PersistentSet.java:435)
	at com.topic.Topic.hashCode(Topic.java:74)
        at com.topic.ScoreRecord.hashCode(ScoreRecord.java:100)

@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((records == null) ? 0 : records.hashCode()); //ошибка на этой строке
		result = prime * result + ((topicId == null) ? 0 : topicId.hashCode());
		result = prime * result
				+ ((topicName == null) ? 0 : topicName.hashCode());
		return result;
	}