I encountering a problem when sending a GET request from Postman to test my endpoints. The same NamedQueries worked before with Derby with just the one Schema, so no need to differentiate then. I have now changed to DB2 running in a local Docker instance and am using Maven to run Open-Liberty Framework to create the endpoints. I am receiving the below error. Do I need to create a orm.xml file with entity-mappings, or do something else to resolve this? I would prefer to do this without more xml files if possible.
Postman:
Error 500: java.lang.NullPointerException: Cannot invoke >"javax.persistence.EntityManager.createNamedQuery(String, java.lang.Class)" because "this.em" is null
Maven:
[INFO] [ERROR ] CWWJP0015E: An error occurred in the org.eclipse.persistence.jpa.PersistenceProvider persistence provider when it attempted to create the container entity manager factory for the jpa-unit persistence unit. The following error occurred: Exception [EclipseLink-28019] (Eclipse Persistence Services - 2.7.9.v20210604-2c549e2208): org.eclipse.persistence.exceptions.EntityManagerSetupException
[INFO] Exception Description: Deployment of PersistenceUnit [jpa-unit] failed. Close all factories for this PersistenceUnit.
[INFO] Internal Exception: Exception [EclipseLink-0] (Eclipse Persistence Services - 2.7.9.v20210604-2c549e2208): org.eclipse.persistence.exceptions.JPQLException
[INFO] Exception Description: Problem compiling [SELECT u FROM Sankofa.Users u].
[INFO] [14, 29] 'Sankofa.Users u' cannot be the first declaration of the FROM clause.
UserDao
package dao;
import java.util.List;
import java.util.concurrent.TimeoutException;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import org.hyperledger.fabric.gateway.ContractException;
import javax.enterprise.context.RequestScoped;
import models.*;
@RequestScoped
public class UserDao {
//DB2 Methods
@PersistenceContext(name = "jpa-unit")
private EntityManager em;
public void createUser(Users user){
em.persist(user);
}
public Users readUser(int userID){
return em.find(Users.class, userID);
}
//NEED TO DO set return limit to 20
public List<Users> readAllUsers(){
return em.createNamedQuery("Users.findAll", Users.class).getResultList();
}
public void updateUser(Users user){
em.merge(user);
}
public void deleteUser(Users userID){
em.remove(userID);
}
public List<Users> findUser(String email){
return em.createNamedQuery("Users.findUser", Users.class)
.setParameter("email", email)
.getResultList();
}
public void createHistory(History hist){
em.persist(hist);
}
//wait this doesnt do anything?
public Users readHistory(int userID){
return em.find(Users.class, userID);
}
public List<History> readAllHistory(){
return em.createNamedQuery("History.findAll", History.class).getResultList();
}
}
Users
package models;
import java.util.HashSet;
import java.util.Objects;
import java.util.Set;
import javax.json.Json;
import javax.json.JsonArrayBuilder;
import javax.json.JsonObject;
import javax.json.JsonObjectBuilder;
import javax.persistence.*;
import java.time.LocalDate;
@Entity
@Table(name = "Users")
@NamedQueries({
@NamedQuery(name = "Users.findAll", query = "SELECT u FROM Users u"),
@NamedQuery(name = "Users.findUser", query = "SELECT usr FROM Users usr WHERE usr.email = :email")
})
public class Users {
private static JsonObjectBuilder builder = Json.createObjectBuilder();
@GeneratedValue(strategy = GenerationType.AUTO)
@Id
@Column(name = "userId")
private int id;
@Column(name = "firstName")
private String firstName;
@Column(name = "lastName")
private String lastName;
@Column(name = "gender")
private String gender;
@Column(name = "address")
private String address;
@Column(name = "email")
private String email;
@Column(name = "password")
private String password;
@Column(name = "dateOfBirth")
private LocalDate dateOfBirth;
Persistence.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.2"
xmlns="http://xmlns.jcp.org/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
http://xmlns.jcp.org/xml/ns/persistence/persistence_2_2.xsd">
<persistence-unit name="jpa-unit" transaction-type="JTA">
<mapping-file>orm.xml</mapping-file>
<properties>
<!-- Connection Specific -->
<property name="hibernate.dialect" value="org.hibernate.dialect.DB2Dialect"/>
<property name="javax.persistence.schema-generation.database.action" value="create" />
<property name="javax.persistence.schema-generation.create-database-schemas" value="true" />
<property name="javax.persistence.schema-generation.scripts.action" value="create" />
<property name="javax.persistence.schema-generation.scripts.create-target" value="create.ddl"/>
</properties>
</persistence-unit>
</persistence>
Server.xml
<server description="Obdoblock REST Server">
<featureManager>
<feature>jaxrs-2.1</feature>
<feature>openapi-3.1</feature>
<feature>jpa-2.2</feature>
<feature>cdi-2.0</feature>
</featureManager>
<httpEndpoint
httpPort="${default.http.port}"
httpsPort="${default.https.port}"
id="defaultHttpEndpoint"
host="*"
/>
<webApplication
location="hyperledger-api.war"
contextRoot="${app.context.root}"
/>
<!-- DB2 Library Configuration -->
<library id="DB2JCCLib">
<file name="${shared.resource.dir}/jcc-11.5.6.0" />
</library>
<dataSource id="DefaultDataSource" jndiName="jdbc/db2">
<jdbcDriver libraryRef="jdbcLib"/>
<properties.db2.jcc
databaseName="testdb"
serverName="localhost"
portNumber="50000"
user="****" password="****"
/>
</dataSource>
</server>
Versions:
- Docker: 20.10.8, build 3967b7d
- DB2: ibm/db2 docker image version 11.5.6
- Maven: 3.8.3
- Java: JDK 14.0.2
If needing any more details, I'm happy to provide them. Thanks, Dylan
