Java Tutorial/EJB3/EJB Query Language
Use EJB QL To Retrieve Entity Bean
File: Customer.java
<source lang="java">
import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.IdClass; @Entity @IdClass(CustomerPK.class) public class Customer implements java.io.Serializable {
private String firstName; private String lastName; private long ssn; public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this.firstName = firstName; } @Id public String getLastName() { return lastName; } public void setLastName(String lastName) { this.lastName = lastName; } @Id public long getSsn() { return ssn; } public void setSsn(long ssn) { this.ssn = ssn; }
} class CustomerPK implements java.io.Serializable {
private String lastName; private long ssn; public CustomerPK() { } public CustomerPK(String lastName, long ssn) { this.lastName = lastName; this.ssn = ssn; } public String getLastName() { return this.lastName; } public void setLastName(String lastName) { this.lastName = lastName; } public long getSsn() { return ssn; } public void setSsn(long ssn) { this.ssn = ssn; } public boolean equals(Object obj) { if (obj == this) return true; if (!(obj instanceof CustomerPK)) return false; CustomerPK pk = (CustomerPK) obj; if (!lastName.equals(pk.lastName)) return false; if (ssn != pk.ssn) return false; return true; } public int hashCode() { return lastName.hashCode() + (int) ssn; }
}</source>