I'm pretty new to JPA and databases in general, and I'm trying to teach myself some of this. I want to know if it's at all possible to turn a List you retrieve of a particular entity into a map. Ultimately I want to get a List of Maps of the all the separate entities.
This is the error that I am getting:
java.lang.ClassCastException: consultant.billing.entity.WorkEntry cannot be cast to java.util.Map
Below is my entity and the code I am trying to run:
@Entity
@Table(name = "work_entry")
@XmlRootElement
@NamedQueries({
@NamedQuery(name = "WorkEntry.findAll", query = "SELECT w FROM WorkEntry w"),
@NamedQuery(name = "WorkEntry.findByWorkEntryId", query = "SELECT w FROM WorkEntry w WHERE w.workEntryId = :workEntryId"),
@NamedQuery(name = "WorkEntry.findByDate", query = "SELECT w FROM WorkEntry w WHERE w.date = :date"),
@NamedQuery(name = "WorkEntry.findByHoursWorked", query = "SELECT w FROM WorkEntry w WHERE w.hoursWorked = :hoursWorked")})
public class WorkEntry implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "work_entry_id")
private Integer workEntryId;
@Column(name = "date")
@Temporal(TemporalType.DATE)
private Date date;
// @Max(value=?) @Min(value=?)//if you know range of your decimal fields consider using these annotations to enforce field validation
@Column(name = "hours_worked")
private Double hoursWorked;
@JoinColumn(name = "activity_id", referencedColumnName = "activity_id")
@ManyToOne
private Activity activityId;
@JoinColumn(name = "customer_id", referencedColumnName = "customer_id")
@ManyToOne
private Customer customerId;
public WorkEntry() {
}
public WorkEntry(Date date, Double hoursWorked, Customer customerId, Activity activityId) {
this.date = date;
this.hoursWorked = hoursWorked;
this.activityId = activityId;
this.customerId = customerId;
}
public WorkEntry(Integer workEntryId) {
this.workEntryId = workEntryId;
}
public Integer getWorkEntryId() {
return workEntryId;
}
public void setWorkEntryId(Integer workEntryId) {
this.workEntryId = workEntryId;
}
public Date getDate() {
return date;
}
public void setDate(Date date) {
this.date = date;
}
public Double getHoursWorked() {
return hoursWorked;
}
public void setHoursWorked(Double hoursWorked) {
this.hoursWorked = hoursWorked;
}
public Activity getActivityId() {
return activityId;
}
public void setActivityId(Activity activityId) {
this.activityId = activityId;
}
public Customer getCustomerId() {
return customerId;
}
public void setCustomerId(Customer customerId) {
this.customerId = customerId;
}
@Override
public int hashCode() {
int hash = 0;
hash += (workEntryId != null ? workEntryId.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof WorkEntry)) {
return false;
}
WorkEntry other = (WorkEntry) object;
if ((this.workEntryId == null && other.workEntryId != null) || (this.workEntryId != null && !this.workEntryId.equals(other.workEntryId))) {
return false;
}
return true;
}
@Override
public String toString() {
return "consultant.billing.entity.WorkEntry[ workEntryId=" + workEntryId + " ]";
}
}
@Entity
@Table(name = "customer")
@XmlRootElement
@NamedQueries({
@NamedQuery(name = "Customer.findAll", query = "SELECT c FROM Customer c"),
@NamedQuery(name = "Customer.findByCustomerId", query = "SELECT c FROM Customer c WHERE c.customerId = :customerId"),
@NamedQuery(name = "Customer.findByFirstName", query = "SELECT c FROM Customer c WHERE c.firstName = :firstName"),
@NamedQuery(name = "Customer.findByLastName", query = "SELECT c FROM Customer c WHERE c.lastName = :lastName"),
@NamedQuery(name = "Customer.findByStreetAddress", query = "SELECT c FROM Customer c WHERE c.streetAddress = :streetAddress"),
@NamedQuery(name = "Customer.findByCity", query = "SELECT c FROM Customer c WHERE c.city = :city"),
@NamedQuery(name = "Customer.findByState", query = "SELECT c FROM Customer c WHERE c.state = :state"),
@NamedQuery(name = "Customer.findByPostalCode", query = "SELECT c FROM Customer c WHERE c.postalCode = :postalCode"),
@NamedQuery(name = "Customer.findByPhoneNumber", query = "SELECT c FROM Customer c WHERE c.phoneNumber = :phoneNumber"),
@NamedQuery(name = "Customer.findByEmail", query = "SELECT c FROM Customer c WHERE c.email = :email")})
public class Customer implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "customer_id")
private Integer customerId;
@Size(max = 75)
@Column(name = "first_name")
private String firstName;
@Size(max = 75)
@Column(name = "last_name")
private String lastName;
@Size(max = 250)
@Column(name = "street_address")
private String streetAddress;
@Size(max = 50)
@Column(name = "city")
private String city;
@Size(max = 50)
@Column(name = "state")
private String state;
@Size(max = 45)
@Column(name = "postal_code")
private String postalCode;
@Size(max = 45)
@Column(name = "phone_number")
private String phoneNumber;
// @Pattern(regexp="[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?", message="Invalid email")//if the field contains email address consider using this annotation to enforce field validation
@Size(max = 250)
@Column(name = "email")
private String email;
@OneToMany(mappedBy = "customerId")
private Collection<ExpenseEntry> expenseEntryCollection;
@OneToMany(mappedBy = "customerId")
private Collection<WorkEntry> workEntryCollection;
code I'm trying to run:
public Customer() {
}
String customerId = request.getParameter("customerId");
Customer customer = customerServ.find(Integer.parseInt(customerId));
request.setAttribute("customer", customer);
String sDate = request.getParameter("sDate");
Date parsedSDate = sdf.parse(sDate);
java.sql.Date sqlSDate = new java.sql.Date(parsedSDate.getTime());
String eDate = request.getParameter("eDate");
Date parsedEDate = sdf.parse(eDate);
java.sql.Date sqlEDate = new java.sql.Date(parsedEDate.getTime());
List<Map> workDone = workServ.getWorkDoneByCustAndDate(Integer.parseInt(customerId), sqlSDate, sqlEDate);
List<Map> expenses = expenseEntServ.getExpenseForCustIdAndDate(Integer.parseInt(customerId), sqlSDate, sqlEDate);
List newInvoice = invoice.getInvoice(workDone,expenses);
Method I'm using to get WorkEntry:
public List<Map> getWorkDoneByCustAndDate(int custId, Date sDate, Date eDate) {
String jpql = "SELECT w FROM WorkEntry w WHERE w.customerId.customerId = :customerId AND w.date BETWEEN :sDate AND :eDate";
Query q = getEntityManager().createQuery(jpql);
q.setParameter("customerId", custId);
q.setParameter("sDate", sDate, TemporalType.DATE);
q.setParameter("eDate", eDate, TemporalType.DATE);
return q.getResultList();
}
You can do that but no with JPA, after you get the list of your Work Entries, you can use Java reflection or more easier, use BeanUtils or JACKSON to convert any Java Bean ( in your case, WorkEntry class) into a Map.
You can see this example of BeanUtils library to achieve this goal.
You can add this code after you get your list:
List<Map> yourList=new ArrayList<Map>();
List<WorkEntry> list=q.getResultList();
for(WorkEntry we:list){
BeanMap map=new BeanMap(we);
yourList.add(map);
}
Hope it helps.