package com.baeldung.persistence.model; import java.io.Serializable; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.OneToOne; @Entity public class Child implements Serializable { @Id @GeneratedValue private long id; @OneToOne(mappedBy = "child") private Parent parent; public Child() { super(); } // API public long getId() { return id; } public void setId(final long id) { this.id = id; } public Parent getParent() { return parent; } public void setParent(final Parent parent) { this.parent = parent; } // @Override public String toString() { final StringBuilder builder = new StringBuilder(); builder.append("Child [id=").append(id).append("]"); return builder.toString(); } }