JPA Cases
Estos Son ejemplos prácticos de generación de tablas de
bases de datos a partir de entidades (@Entity)
annotations en Java JPA
Enlace a archivo work con imagenes
JPA_1_Simple Table
@Entity
public class Tabla implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String nombre;
private String apellido;
private Double valDouble;
private Integer valInteger;
private boolean valboolean;
@Temporal(DATE)
private java.util.Date utilDate;
private java.sql.Date sqlDate;
private Time sqlTime;
private Timestamp sqlTimeStamp;
@Lob
private String descripcion;
@Lob
@Column(name="EMP_PIC",columnDefinition="BLOB NOT NULL")
private byte[] pic;
public Long getId() {
return id;
} …
Genera
drop table DEVELOP.TABLA cascade
constraints;
/*==============================================================*/
/* Table: TABLA */
/*==============================================================*/
create table DEVELOP.TABLA
(
ID
NUMBER(19) not null,
APELLIDO
VARCHAR2(255),
DESCRIPCION CLOB,
NOMBRE
VARCHAR2(255),
EMP_PIC BLOB not null,
SQLDATE DATE,
SQLTIME TIMESTAMP,
SQLTIMESTAMP TIMESTAMP,
UTILDATE DATE,
VALDOUBLE NUMBER(19,4),
VALINTEGER NUMBER(10),
VALBOOLEAN
NUMBER(1) default 0,
constraint SYS_C007261 primary key (ID)
using index pctfree 10
initrans 2
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
logging
tablespace DEVELOP_TABSPACE
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
lob
(DESCRIPCION)
store as
basicfile
(tablespace DEVELOP_TABSPACE
chunk 8192
retention nocache);
drop table DEVELOP.SEQUENCE cascade
constraints;
/*==============================================================*/
/* Table: SEQUENCE */
/*==============================================================*/
create table DEVELOP.SEQUENCE
(
SEQ_NAME
VARCHAR2(50) not null,
SEQ_COUNT NUMBER,
constraint SYS_C007263 primary key (SEQ_NAME)
using index pctfree 10
initrans 2
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
logging
tablespace DEVELOP_TABSPACE
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
monitoring
noparallel;
JPA_2_SimpleTable
@Entity
public class Tabla implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE,
generator="TABLA_SEQ")
@Column(name="TABLA_ID")
private Long id;
private String nombre;
…
drop table DEVELOP.TABLA cascade
constraints;
/*==============================================================*/
/* Table: TABLA
*/
/*==============================================================*/
create table DEVELOP.TABLA
(
TABLA_ID NUMBER(19) not null,
APELLIDO
VARCHAR2(255),
DESCRIPCION CLOB,
NOMBRE VARCHAR2(255),
EMP_PIC BLOB not null,
SQLDATE DATE,
SQLTIME TIMESTAMP,
SQLTIMESTAMP TIMESTAMP,
UTILDATE DATE,
VALDOUBLE NUMBER(19,4),
VALINTEGER NUMBER(10),
VALBOOLEAN
NUMBER(1) default 0,
constraint SYS_C007266 primary key (TABLA_ID)
using index pctfree 10
initrans 2
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
logging
tablespace DEVELOP_TABSPACE
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
lob
(DESCRIPCION)
store as
basicfile
(tablespace DEVELOP_TABSPACE
chunk 8192
retention nocache);
JPA_3_SimpleTable
@Entity
public class Tabla implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.TABLE,
generator="TABLA_GEN")
@Column(name="TABLA_ID")
private Long id;
private String nombre;
…
drop table DEVELOP.TABLA cascade
constraints;
/*==============================================================*/
/* Table: TABLA
*/
/*==============================================================*/
create table DEVELOP.TABLA
(
TABLA_ID
NUMBER(19) not null,
APELLIDO
VARCHAR2(255),
DESCRIPCION CLOB,
NOMBRE VARCHAR2(255),
EMP_PIC BLOB not null,
SQLDATE DATE,
SQLTIME TIMESTAMP,
SQLTIMESTAMP TIMESTAMP,
UTILDATE DATE,
VALDOUBLE NUMBER(19,4),
VALINTEGER NUMBER(10),
VALBOOLEAN
NUMBER(1) default 0,
constraint SYS_C007269 primary key (TABLA_ID)
using index pctfree 10
initrans 2
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
logging
tablespace DEVELOP_TABSPACE
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
lob
(DESCRIPCION)
store as
basicfile
(tablespace DEVELOP_TABSPACE
chunk 8192
retention nocache);
drop table DEVELOP.SEQUENCE cascade
constraints;
/*==============================================================*/
/* Table: SEQUENCE
*/
/*==============================================================*/
create table DEVELOP.SEQUENCE
(
SEQ_NAME
VARCHAR2(50) not null,
SEQ_COUNT NUMBER,
constraint SYS_C007271 primary key (SEQ_NAME)
using index pctfree 10
initrans 2
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
logging
tablespace DEVELOP_TABSPACE
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
monitoring
noparallel;
JPA_4_SimpleTableElemColl
@Entity
public class Tabla implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.TABLE,
generator="TABLA_GEN")
@Column(name="TABLA_ID")
private Long id;
private String nombre;
private String apellido;
private Double valDouble;
private Integer valInteger;
private boolean valboolean;
@Temporal(DATE)
private java.util.Date utilDate;
private java.sql.Date sqlDate;
private Time sqlTime;
private Timestamp sqlTimeStamp;
@Lob
private String descripcion;
@Lob
@Column(name="EMP_PIC",columnDefinition="BLOB NOT
NULL")
//@Column(name="EMP_PIC",columnDefinition="LONGBLOB
NOT NULL") //en caso de MySQL
private byte[] pic;
@ElementCollection //uses default
table TABLA_ELEMCOLL
@Column(name="DetalleTabla", length=50)
private Set<String> ElemColl = new HashSet();
…
drop table DEVELOP.TABLA cascade constraints;
/*==============================================================*/
/* Table: TABLA
*/
/*==============================================================*/
create table DEVELOP.TABLA
(
TABLA_ID
NUMBER(19) not null,
APELLIDO
VARCHAR2(255),
DESCRIPCION CLOB,
NOMBRE VARCHAR2(255),
EMP_PIC BLOB not null,
SQLDATE DATE,
SQLTIME TIMESTAMP,
SQLTIMESTAMP TIMESTAMP,
UTILDATE DATE,
VALDOUBLE NUMBER(19,4),
VALINTEGER NUMBER(10),
VALBOOLEAN
NUMBER(1) default 0,
constraint SYS_C006999 primary key (TABLA_ID)
using index pctfree 10
initrans 2
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
logging
tablespace DEVELOP_TABSPACE
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
lob
(DESCRIPCION)
store as
basicfile
(tablespace DEVELOP_TABSPACE
chunk 8192
retention nocache);
alter table DEVELOP.TABLA_ELEMCOLL
drop constraint TABLA_ELEMCOLL_TABLA_TABLA_ID;
drop table DEVELOP.TABLA_ELEMCOLL
cascade constraints;
/*==============================================================*/
/* Table: TABLA_ELEMCOLL */
/*==============================================================*/
create table DEVELOP.TABLA_ELEMCOLL
(
TABLA_TABLA_ID
NUMBER(19),
DETALLETABLA VARCHAR2(50)
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
monitoring
noparallel;
alter table DEVELOP.TABLA_ELEMCOLL
add constraint TABLA_ELEMCOLL_TABLA_TABLA_ID foreign key
(TABLA_TABLA_ID)
references DEVELOP.TABLA (TABLA_ID)
not deferrable;
drop table DEVELOP.SEQUENCE cascade
constraints;
/*==============================================================*/
/* Table: SEQUENCE
*/
/*==============================================================*/
create table DEVELOP.SEQUENCE
(
SEQ_NAME
VARCHAR2(50) not null,
SEQ_COUNT NUMBER,
constraint SYS_C007002 primary key (SEQ_NAME)
using index pctfree 10
initrans 2
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
logging
tablespace DEVELOP_TABSPACE
)
pctfree 10
initrans 1
storage
(
initial 64K
next 1024K
minextents 1
maxextents unlimited
)
tablespace DEVELOP_TABSPACE
logging
nocompress
monitoring
noparallel;
En caso de MySQL
drop table if exists wsp.tabla;
/*==============================================================*/
/* Table: tabla
*/
/*==============================================================*/
create table wsp.tabla
(
TABLA_ID bigint(20)
not null,
APELLIDO
national varchar(255),
DESCRIPCION national longtext,
NOMBRE national
varchar(255),
EMP_PIC longblob not
null,
SQLDATE date,
SQLTIME time,
SQLTIMESTAMP datetime,
UTILDATE date,
VALDOUBLE double,
VALINTEGER int(11),
VALBOOLEAN tinyint(1)
default 0,
primary key (TABLA_ID)
);
drop table if exists
wsp.tabla_elemcoll;
/*==============================================================*/
/* Table: tabla_elemcoll */
/*==============================================================*/
create table wsp.tabla_elemcoll
(
Tabla_TABLA_ID
bigint(20),
DetalleTabla national varchar(50)
);
alter table wsp.tabla_elemcoll add
constraint FK_Tabla_ELEMCOLL_Tabla_TABLA_ID foreign key (Tabla_TABLA_ID)
references wsp.tabla (TABLA_ID);
drop table if exists wsp.sequence;
/*==============================================================*/
/* Table: sequence */
/*==============================================================*/
create table wsp.sequence
(
SEQ_NAME national
varchar(50) not null,
SEQ_COUNT
decimal(38,0),
primary key (SEQ_NAME)
);
JPA Relationships
ManyToOne Mappings
Employee(Many) Department(One)
@Entity
public class Employee implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private Long salary;
@ManyToOne
private Department department;
…
}
@Entity
public class Department implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
…
}
DB scripts from Entity classes…
CREATE TABLE EMPLOYEE (ID NUMBER(19)
NOT NULL, NAME VARCHAR2(255) NULL, SALARY NUMBER(19) NULL, DEPARTMENT_ID
NUMBER(19) NULL, PRIMARY KEY (ID))
CREATE TABLE DEPARTMENT (ID
NUMBER(19) NOT NULL, NAME VARCHAR2(255) NULL, PRIMARY KEY (ID))
ALTER TABLE EMPLOYEE ADD CONSTRAINT
FK_EMPLOYEE_DEPARTMENT_ID FOREIGN KEY (DEPARTMENT_ID) REFERENCES DEPARTMENT
(ID)
CREATE TABLE SEQUENCE (SEQ_NAME VARCHAR2(50)
NOT NULL, SEQ_COUNT NUMBER(38) NULL, PRIMARY KEY (SEQ_NAME))
INSERT INTO SEQUENCE(SEQ_NAME,
SEQ_COUNT) values ('SEQ_GEN', 0)
ManyToOne JoinColumn
@Entity
public class Employee implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private Long salary;
@ManyToOne
@JoinColumn(name="DEPT_ID")
private Department department;
…
}
@Entity
public class Department implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
…
}
CREATE TABLE EMPLOYEE (ID NUMBER(19)
NOT NULL, NAME VARCHAR2(255) NULL, SALARY NUMBER(19) NULL, DEPT_ID NUMBER(19)
NULL, PRIMARY KEY (ID))
CREATE TABLE DEPARTMENT (ID
NUMBER(19) NOT NULL, NAME VARCHAR2(255) NULL, PRIMARY KEY (ID))
ALTER TABLE EMPLOYEE ADD CONSTRAINT
FK_EMPLOYEE_DEPT_ID FOREIGN KEY (DEPT_ID) REFERENCES DEPARTMENT (ID)
CREATE TABLE SEQUENCE (SEQ_NAME
VARCHAR2(50) NOT NULL, SEQ_COUNT NUMBER(38) NULL, PRIMARY KEY (SEQ_NAME))
INSERT INTO SEQUENCE(SEQ_NAME,
SEQ_COUNT) values ('SEQ_GEN', 0)
OneToOne Mappings
Employee
(one) --- ParkingSpace (one)
@Entity
public class Employee implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private Long salary;
@OneToOne
@JoinColumn(name="PSPACE_ID")
private ParkingSpace parkingSpace;
…
}
@Entity
public class ParkingSpace implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private int lot;
private String location;
…
}
CREATE TABLE EMPLOYEE (ID NUMBER(19)
NOT NULL, NAME VARCHAR2(255) NULL, SALARY NUMBER(19) NULL, PSPACE_ID NUMBER(19)
NULL, PRIMARY KEY (ID))
CREATE TABLE PARKINGSPACE (ID
NUMBER(19) NOT NULL, LOCATION VARCHAR2(255) NULL, LOT NUMBER(10) NULL, PRIMARY
KEY (ID))
ALTER TABLE EMPLOYEE ADD CONSTRAINT
FK_EMPLOYEE_PSPACE_ID FOREIGN KEY (PSPACE_ID) REFERENCES PARKINGSPACE (ID)
CREATE TABLE SEQUENCE (SEQ_NAME
VARCHAR2(50) NOT NULL, SEQ_COUNT NUMBER(38) NULL, PRIMARY KEY (SEQ_NAME))
INSERT INTO SEQUENCE(SEQ_NAME,
SEQ_COUNT) values ('SEQ_GEN', 0)
Check that the foreing key must have
a uniqueness constraint, and it doesn’t happen. So in case of MySQL is added
manually the constraint
ALTER TABLE EMPLOYEE ADD UNIQUE
PARKINGSPACECONSTRAINT (DEPT_ID);
In Oracle
ALTER TABLE EMPLOYEE ADD CONTRAINT
PARKINGSPACECONSTRAINT UNIQUE (DEPT_ID)
When populate with data test report
an error of duplicates.
OneToOne Bidirectional
@Entity
public class Employee implements
Serializable {
private static final long
serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private Long salary;
@OneToOne
@JoinColumn(name="PSPACE_ID")
private ParkingSpace parkingSpace;
@Entity
public class ParkingSpace implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private int lot;
private String location;
@OneToOne(mappedBy="parkingSpace")
private Employee employee;
CREATE TABLE EMPLOYEE (ID NUMBER(19)
NOT NULL, NAME VARCHAR2(255) NULL, SALARY NUMBER(19) NULL, PSPACE_ID NUMBER(19)
NULL, PRIMARY KEY (ID))
CREATE TABLE PARKINGSPACE (ID
NUMBER(19) NOT NULL, LOCATION VARCHAR2(255) NULL, LOT NUMBER(10) NULL, PRIMARY
KEY (ID))
ALTER TABLE EMPLOYEE ADD CONSTRAINT
FK_EMPLOYEE_PSPACE_ID FOREIGN KEY (PSPACE_ID) REFERENCES PARKINGSPACE (ID)
CREATE TABLE SEQUENCE (SEQ_NAME
VARCHAR2(50) NOT NULL, SEQ_COUNT NUMBER(38) NULL, PRIMARY KEY (SEQ_NAME))
INSERT INTO SEQUENCE(SEQ_NAME,
SEQ_COUNT) values ('SEQ_GEN', 0)
The generated script is the same as
the OneToOne unidirection relation???
OneToMany
Employee
(many) ---- Department (one)
@Entity
public class Employee implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private Long salary;
private Department department;
…
}
@Entity
public class Department implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
@OneToMany(cascade=CascadeType.PERSIST,mappedBy="department")
//(fetch=FetchType.LAZY, cascade=CascadeType.PERSIST)
private List<Employee> employees = new ArrayList<Employee>();
…
}
Script generated for MySQL:
CREATE TABLE EMPLOYEE (ID BIGINT NOT
NULL, NAME VARCHAR(255), SALARY BIGINT, DEPARTMENT_ID BIGINT, PRIMARY KEY (ID))
CREATE TABLE DEPARTMENT (ID BIGINT
NOT NULL, NAME VARCHAR(255), PRIMARY KEY (ID))
ALTER TABLE EMPLOYEE ADD CONSTRAINT
FK_EMPLOYEE_DEPARTMENT_ID FOREIGN KEY (DEPARTMENT_ID) REFERENCES DEPARTMENT
(ID)
CREATE TABLE SEQUENCE (SEQ_NAME
VARCHAR(50) NOT NULL, SEQ_COUNT DECIMAL(38), PRIMARY KEY (SEQ_NAME))
INSERT INTO SEQUENCE(SEQ_NAME,
SEQ_COUNT) values ('SEQ_GEN', 0)
OneToMany Version 2
@Entity
public class Employee implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy =
GenerationType.TABLE,generator="EMPLOYEE_GEN")
@Column(name="EMP_ID")
private Long id;
private String name;
private Long salary;
@ManyToOne(targetEntity=Department.class, fetch=FetchType.LAZY)
private Department department;
…
}
@Entity
public class Department implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy =
GenerationType.TABLE,generator="DEPARTMENT_GEN")
@Column(name="DEP_ID")
private Long id;
private String name;
@OneToMany(cascade=CascadeType.ALL,mappedBy="department")
//(fetch=FetchType.LAZY, cascade=CascadeType.PERSIST)
private List<Employee> employees = new
ArrayList<Employee>();
…
}
MySQL script:
ManyToMany with out CascadeType.Persist
@Entity
public class Employee implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
//@GeneratedValue(strategy =
GenerationType.TABLE,generator="EMP_TAB")
//@TableGenerator(name="EMP_TAB",table="EMP_GEN")
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="EMP_ID")
private Long id;
private String name;
private Long salary;
@ManyToMany//(cascade = {CascadeType.PERSIST, CascadeType.MERGE})
@JoinTable(name="EMP_PROJ",
joinColumns=@JoinColumn(name="EMP_ID"),
inverseJoinColumns=@JoinColumn(name="PROJ_ID"))
private List<Project> projects = new ArrayList<Project>();
…
}
@Entity
public class Project implements
Serializable {
private static final long serialVersionUID = 1L;
@Id
//@GeneratedValue(strategy =
GenerationType.TABLE,generator="PROJ_TAB")
//@TableGenerator(name="PROJ_TAB",table="PROJ_GEN")
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="PROJ_ID")
private Long id;
private String name;
@ManyToMany(mappedBy="projects")
private List<Employee> employees = new
ArrayList<Employee>();
…
}
public class Populate {
public static void main(String... args) {
EntityManagerFactory emf =
createEntityManagerFactory("JPArelationshipsPU");
EntityManager em =
emf.createEntityManager();
populate(emf);
emf.close();
}
private static void populate(EntityManagerFactory emf) {
EntityManager em =
emf.createEntityManager();
Employee emp = new Employee();
emp.setName("Un
Empleado");
emp.setSalary(1203L);
Employee emp2 = new Employee();
emp2.setName("Empleado Dos");
emp2.setSalary(77777L);
Employee emp3 = new Employee();
emp3.setName("Empleado sin
Departamento");
emp3.setSalary(9999L);
Project proj = new Project();
proj.setName("Projecto ONE");
Project proj2 = new Project();
proj2.setName("Projecto X");
emp.getProjects().add(proj);
emp.getProjects().add(proj2);
emp2.getProjects().add(proj2);
proj.getEmployees().add(emp2);
proj2.getEmployees().add(emp);
em.getTransaction().begin();
em.persist(emp);
em.persist(emp2);
em.persist(proj); // Without PERSIST this is necesary
em.persist(proj2); //
Withoiut PERSIST this is necesary
em.getTransaction().commit();
//em.flush();
em.close();
}
If only is PERSISTED the employee
with out CascadeType.PERSIST and not is PERSISTED the project the following
error will throws:
[EL
Warning]: java.lang.IllegalStateException: During synchronization a new object
was found through a relationship that was not marked cascade PERSIST:
org.jamr.model.Project[ id=null ].
Exception
in thread "main" javax.persistence.RollbackException:
java.lang.IllegalStateException: During synchronization a new object was found
through a relationship that was not marked cascade PERSIST:
org.jamr.model.Project[ id=null ].
at
org.eclipse.persistence.internal.jpa.transaction.EntityTransactionImpl.commit(EntityTransactionImpl.java:157)
at
com.jamr.example.Populate.populate(Populate.java:63)
at
com.jamr.example.Populate.main(Populate.java:25)
Caused
by: java.lang.IllegalStateException: During synchronization a new object was
found through a relationship that was not marked cascade PERSIST:
org.jamr.model.Project[ id=null ].
at
org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.discoverUnregisteredNewObjects(RepeatableWriteUnitOfWork.java:310)
at
org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.calculateChanges(UnitOfWorkImpl.java:723)
at
org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.commitToDatabaseWithChangeSet(UnitOfWorkImpl.java:1516)
at
org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.commitRootUnitOfWork(RepeatableWriteUnitOfWork.java:277)
at
org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.commitAndResume(UnitOfWorkImpl.java:1169)
at
org.eclipse.persistence.internal.jpa.transaction.EntityTransactionImpl.commit(EntityTransactionImpl.java:132)
... 2 more
Otherwise with employee with
CascadeType.PERSIST, is not necessary Persist de project. Is automatically
persisted by his relationship marked with employee.
