Java HTTP状态500-保存hibernate OneTOMany关系时出现内部服务器错误

我正在进行OneToMany关系，数据保存正确，但apache tomcat服务器给出错误HTTP状态500-内部服务器错误

捐赠者类别：

@Entity
public class DonorClass {

@Id @GeneratedValue(strategy=GenerationType.AUTO)
private int donorId;
private String firstName;
private String lastName;
private int age;
private String cnic;
private String contactNumber;
private String homeNumber;
private String country;
private String city;
private String town;
private String streetNo;
private String houseNo;
private String email;

@OneToMany(cascade = CascadeType.ALL, mappedBy="donor")
private Set<BloodDonorClass> blood;

public int getDonorId() {
    return donorId;
}
public void setDonorId(int donorId) {
    this.donorId = donorId;
}
public String getFirstName() {
    return firstName;
}
public void setFirstName(String firstName) {
    this.firstName = firstName;
}
public String getLastName() {
    return lastName;
}
public void setLastName(String lastName) {
    this.lastName = lastName;
}
public int getAge() {
    return age;
}
public void setAge(int age) {
    this.age = age;
}
public String getCnic() {
    return cnic;
}
public void setCnic(String cnic) {
    this.cnic = cnic;
}
public String getContactNumber() {
    return contactNumber;
}
public void setContactNumber(String contactNumber) {
    this.contactNumber = contactNumber;
}
public String getHomeNumber() {
    return homeNumber;
}
public void setHomeNumber(String homeNumber) {
    this.homeNumber = homeNumber;
}
public String getCountry() {
    return country;
}
public void setCountry(String country) {
    this.country = country;
}
public String getCity() {
    return city;
}
public void setCity(String city) {
    this.city = city;
}
public String getTown() {
    return town;
}
public void setTown(String town) {
    this.town = town;
}
public String getStreetNo() {
    return streetNo;
}
public void setStreetNo(String streetNo) {
    this.streetNo = streetNo;
}
public String getHouseNo() {
    return houseNo;
}
public void setHouseNo(String houseNo) {
    this.houseNo = houseNo;
}
public String getEmail() {
    return email;
}
public void setEmail(String email) {
    this.email = email;
}

public Set<BloodDonorClass> getBlood() {
    return blood;
}

public void setBlood(Set<BloodDonorClass> blood) {
    this.blood = blood;
}|
}

血液和捐赠者对象类：

public class BloodDonorObjectClass {

private DonorClass donor;
private BloodDonorClass blood;
public DonorClass getDonor() {
    return donor;
}
public void setDonor(DonorClass donor) {
    this.donor = donor;
}
public BloodDonorClass getBlood() {
    return blood;
}
public void setBlood(BloodDonorClass blood) {
    this.blood = blood;
}
}

献血者分类服务等级：

SessionFactory sessionFactory = null;

public BloodDonorObjectClass addNewDonor(BloodDonorObjectClass bloodDonor){
    try{
        DonorClass donor = new DonorClass();
        BloodDonorClass blood = new BloodDonorClass();
        blood = (BloodDonorClass)bloodDonor.getBlood();
        donor = (DonorClass)bloodDonor.getDonor();
        sessionFactory = new Configuration().configure().buildSessionFactory();
        Session session = sessionFactory.openSession();
        session.beginTransaction();
        blood.setDonor(donor);
        HashSet<BloodDonorClass> bloods = new HashSet<BloodDonorClass>();
        bloods.add(blood);
        donor.setBlood(bloods);
        session.save(donor);
        session.getTransaction().commit();
        session.close();
    }catch(Exception ex){
        ex.printStackTrace();
    }
    return bloodDonor;
}
}

控制台输出：

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Hibernate: select nextval ('hibernate_sequence')
Hibernate: select nextval ('hibernate_sequence')
Hibernate: insert into DonorClass (age, city, cnic, contactNumber, country, email, firstName, homeNumber, houseNo, lastName, streetNo, town, donorId) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
Hibernate: insert into BloodDonorClass (bloodType, donor_id, price, bloodId) values (?, ?, ?, ?)

---

我很感激：）

“内部服务器错误”可能是任何错误。请在服务器端发布您获得的堆栈跟踪。@Berger控制台输出已添加，不是catalina.out显示任何错误堆栈吗？@Berger堆栈中未显示任何错误trace@Berger你能告诉我原因吗

@Path("bloodresource")
public class BloodResourceNew {

BloodDonorClassService bloodService = new BloodDonorClassService();

@Path("new")
@POST
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public BloodDonorObjectClass addNew(BloodDonorObjectClass blood){
    return bloodService.addNewDonor(blood);
}
}

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Hibernate: select nextval ('hibernate_sequence')
Hibernate: select nextval ('hibernate_sequence')
Hibernate: insert into DonorClass (age, city, cnic, contactNumber, country, email, firstName, homeNumber, houseNo, lastName, streetNo, town, donorId) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
Hibernate: insert into BloodDonorClass (bloodType, donor_id, price, bloodId) values (?, ?, ?, ?)