Admin: 1 версия

2010-06-01T05:18:15Z

1 версия

в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== Create Table From Table Generator ==

File: Student.java



<source lang="java">
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.TableGenerator;
@Entity
public class Student {
@TableGenerator(name = "Address_Gen", table = "ID_GEN", pkColumnName = "GEN_NAME", valueColumnName = "GEN_VAL", pkColumnValue = "Addr_Gen", initialValue = 10000, allocationSize = 100)
@Id
@GeneratedValue(strategy = GenerationType.TABLE, generator = "Address_Gen")
private int id;
transient private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String toString() {
return "\n\nID:" + id + "\nName:" + name + "\n\n";
}
}</source>



== Create Your Own Table For Table Generator ==

File: Student.java



<source lang="java">
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.TableGenerator;
@Entity
public class Student {
@Id
@TableGenerator(name = "EmpPkGen",
table = "ID_GEN",
pkColumnName = "GEN_NAME",
pkColumnValue = "Emp_Gen",
valueColumnName = "GEN_VAL",
initialValue = 0,
allocationSize = 100
)
@GeneratedValue(strategy=GenerationType.TABLE)
/*create table id_gen (
gen_name varchar(80),
gen_val integer,
constraint pk_id_gen
primary key (gen_name)
);
*/
private int id;
transient private String name;

public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

public String toString() {
return "\n\nID:" + id + "\nName:" + name + "\n\n";
}
}</source>



== Generated Value Based On Sequence Generator ==

File: Student.java



<source lang="java">
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.SequenceGenerator;
@Entity
public class Student {
@SequenceGenerator(name="Emp_Gen", sequenceName="Emp_Seq")
@Id @GeneratedValue(generator="Emp_Gen")
private int id;
private String name;

public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

public String toString() {
return "\n\nID:" + id + "\nName:" + name + "\n\n";
}
}</source>



== Generate ID From a Table ==

File: Student.java



<source lang="java">
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.TableGenerator;
@Entity
public class Student {
@TableGenerator(name = "Address_Gen", table = "ID_GEN", pkColumnName = "GEN_NAME", valueColumnName = "GEN_VAL", pkColumnValue = "Addr_Gen", initialValue = 10000, allocationSize = 100)
@Id
@GeneratedValue(strategy = GenerationType.TABLE, generator = "Address_Gen")
private int id;
transient private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String toString() {
return "\n\nID:" + id + "\nName:" + name + "\n\n";
}
}</source>



== ID Generation Type: AUTO ==

File: Helper.java



<source lang="java">
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Helper {
public static void checkData() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
Connection conn = DriverManager.getConnection("jdbc:hsqldb:data/tutorial", "sa", "");
Statement st = conn.createStatement();
ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
while (mrs.next()) {
String tableName = mrs.getString(3);
System.out.println("\n\n\n\nTable Name: "+ tableName);
ResultSet rs = st.executeQuery("select * from " + tableName);
ResultSetMetaData metadata = rs.getMetaData();
while (rs.next()) {
System.out.println(" Row:");
for (int i = 0; i < metadata.getColumnCount(); i++) {
System.out.println(" Column Name: "+ metadata.getColumnLabel(i + 1)+ ", ");
System.out.println(" Column Type: "+ metadata.getColumnTypeName(i + 1)+ ": ");
Object value = rs.getObject(i + 1);
System.out.println(" Column Value: "+value+"\n");
}
}
}
}
}</source>



== ID Generation Type: IDENTITY ==

File: Main.java



<source lang="java">
import java.sql.Timestamp;
import java.util.List;
import java.util.UUID;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
public class Main {
static EntityManagerFactory emf = Persistence.createEntityManagerFactory("JPAService");
static EntityManager em = emf.createEntityManager();
public static void main(String[] a) throws Exception {
em.getTransaction().begin();

Student student = new Student();
student.setName("Joe");

em.persist(student);
em.flush();
em.getTransaction().rumit();

Query query = em.createQuery("SELECT e FROM Student e");
List<Student> list = (List<Student>) query.getResultList();
System.out.println(list);

em.close();
emf.close();

Helper.checkData();
}
}</source>



== ID Generation Type: SEQUENCE ==

File: Main.java



<source lang="java">
import java.sql.Timestamp;
import java.util.List;
import java.util.UUID;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
public class Main {
static EntityManagerFactory emf = Persistence.createEntityManagerFactory("JPAService");
static EntityManager em = emf.createEntityManager();
public static void main(String[] a) throws Exception {
em.getTransaction().begin();

Student student = new Student();
student.setName("Joe");

em.persist(student);
em.flush();
em.getTransaction().rumit();

Query query = em.createQuery("SELECT e FROM Student e");
List<Student> list = (List<Student>) query.getResultList();
System.out.println(list);

em.close();
emf.close();

Helper.checkData();
}
}</source>



== ID Generation Type: TABLE ==

File: Helper.java



<source lang="java">
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Helper {
public static void checkData() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
Connection conn = DriverManager.getConnection("jdbc:hsqldb:data/tutorial", "sa", "");
Statement st = conn.createStatement();
ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
while (mrs.next()) {
String tableName = mrs.getString(3);
System.out.println("\n\n\n\nTable Name: "+ tableName);
ResultSet rs = st.executeQuery("select * from " + tableName);
ResultSetMetaData metadata = rs.getMetaData();
while (rs.next()) {
System.out.println(" Row:");
for (int i = 0; i < metadata.getColumnCount(); i++) {
System.out.println(" Column Name: "+ metadata.getColumnLabel(i + 1)+ ", ");
System.out.println(" Column Type: "+ metadata.getColumnTypeName(i + 1)+ ": ");
Object value = rs.getObject(i + 1);
System.out.println(" Column Value: "+value+"\n");
}
}
}
}
}</source>



== JPA Create Sequence Table For You ==

File: Helper.java



<source lang="java">
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Helper {
public static void checkData() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
Connection conn = DriverManager.getConnection("jdbc:hsqldb:data/tutorial", "sa", "");
Statement st = conn.createStatement();
ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
while (mrs.next()) {
String tableName = mrs.getString(3);
System.out.println("\n\n\n\nTable Name: "+ tableName);
ResultSet rs = st.executeQuery("select * from " + tableName);
ResultSetMetaData metadata = rs.getMetaData();
while (rs.next()) {
System.out.println(" Row:");
for (int i = 0; i < metadata.getColumnCount(); i++) {
System.out.println(" Column Name: "+ metadata.getColumnLabel(i + 1)+ ", ");
System.out.println(" Column Type: "+ metadata.getColumnTypeName(i + 1)+ ": ");
Object value = rs.getObject(i + 1);
System.out.println(" Column Value: "+value+"\n");
}
}
}
}
}</source>



== Sequence Generator Name Init Value And Size ==

File: Customer.java



<source lang="java">
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.PostLoad;
import javax.persistence.PostPersist;
import javax.persistence.PostRemove;
import javax.persistence.PostUpdate;
import javax.persistence.PrePersist;
import javax.persistence.PreRemove;
import javax.persistence.PreUpdate;
import javax.persistence.SequenceGenerator;
@Entity
@SequenceGenerator(name = "SequenceIdGenerator",
sequenceName = "SEQ_ID_GEN", initialValue = 100,
allocationSize = 20)
public class Customer implements java.io.Serializable {
@Id
@GeneratedValue(generator = "SequenceIdGenerator")
private int id;
private String lastName;
private String firstName;

public int getId() {
return id;
}
public void setId(int pk) {
id = pk;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
@PrePersist
public void prePersist() {
System.out.println("@PrePersist");
}
@PostPersist
public void postPersist() {
System.out.println("@PostPersist");
}
@PostLoad
public void postLoad() {
System.out.println("@PostLoad");
}
@PreUpdate
public void preUpdate() {
System.out.println("@PreUpdate");
}
@PostUpdate
public void postUpdate() {
System.out.println("@PostUpdate");
}
@PreRemove
public void preRemove() {
System.out.println("@PreRemove");
}
@PostRemove
public void postRemove() {
System.out.println("@PostRemove");
}
}</source>



== Use Sequence Generator ==

File: Student.java



<source lang="java">
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.SequenceGenerator;
@Entity
public class Student {
@SequenceGenerator(name="Emp_Gen", sequenceName="Emp_Seq")
@Id @GeneratedValue(generator="Emp_Gen")
private int id;
private String name;

public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

public String toString() {
return "\n\nID:" + id + "\nName:" + name + "\n\n";
}
}</source>

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Admin: 1 версия

в 17:44, 31 мая 2010