BaseEntity.java

package ru.javawebinar.topjava.model;

import org.hibernate.Hibernate;
import org.springframework.data.domain.Persistable;

import javax.persistence.*;

/**
 * User: gkislin
 * Date: 22.08.2014
 * <p>
 * Do not manipulate new (transient) entries in HashSet/HashMap without overriding hashCode
 * http://stackoverflow.com/a/39827962/548473
 *
 * @see org.springframework.data.jpa.domain.AbstractPersistable
 */
@MappedSuperclass
// http://stackoverflow.com/questions/594597/hibernate-annotations-which-is-better-field-or-property-access
@Access(AccessType.FIELD)
//@JsonAutoDetect(fieldVisibility = ANY, getterVisibility = NONE, isGetterVisibility = NONE, setterVisibility = NONE)
public class BaseEntity implements Persistable<Integer> {
    public static final int START_SEQ = 100000;

    @Id
    @SequenceGenerator(name = "global_seq", sequenceName = "global_seq", allocationSize = 1)
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "global_seq")
    // PROPERTY access for id due to bug: https://hibernate.atlassian.net/browse/HHH-3718
    @Access(value = AccessType.PROPERTY)
    protected Integer id;

    public BaseEntity() {
    }

    protected BaseEntity(Integer id) {
        this.id = id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    @Override
    public Integer getId() {
        return id;
    }

    @Override
    public boolean isNew() {
        return (getId() == null);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || !getClass().equals(Hibernate.getClass(o))) {
            return false;
        }
        BaseEntity that = (BaseEntity) o;

        return null != getId() && getId().equals(that.getId());
    }

    @Override
    public int hashCode() {
        return (getId() == null) ? 0 : getId();
    }
}