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Generieren Sie Tabellen aus Entity-Klassen in Hibernate

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1- Das Zweck des Unterlagen

Das Dokument wird nach der Quelle vom ... geschrieben:
  • Hibernate 5.2.2.Final

  • Eclipse 4.6 (MARS)

Im Dokument führe ich Sie bei der Erstellung eines Tabellessystem auf einer Database (Oracle, MySQL, SQL Server, ..) nach der Grundlage von Klasse Entity. Die erstellten Tabelle haben die vollen Constraints in der Klasse Entity.

Beachten Sie, dass Hibernate mit allen Database umgehen kann. Deshalb brauchen Sie bei der Umwandlung zu den anderen Database die Kode des Programm nicht ändern. Allerdings sollen Sie ein System der Tabelle in database erstellen. Hibernate unterstützt Sie bei der Erstellung eines System vom Tabelle aus der Klasse Entity 
Das Dokument ist das nächste Teil vom "Die Führung über die Programmierung von Hibernate für den Anfänger'', das Sie hier sehen können:

2- Maven Project erstellen und die Bibliothek melden

Im pom.xml melde ich die Bibliothek Hibernate 5, und die Bibliothek JDBC für die verchiedenen Database wie Oracle, MySQL und SQL Server.
pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
  http://maven.apache.org/xsd/maven-4.0.0.xsd">
 
  <modelVersion>4.0.0</modelVersion>

  <groupId>org.o7planning</groupId>
  <artifactId>HibernateGenerateTables</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>HibernateGenerateTables</name>
  <url>http://maven.apache.org</url>


   <properties>
       <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
   </properties>


   <repositories>
       <!-- Repository for ORACLE JDBC Driver -->
       <repository>
           <id>codelds</id>
           <url>https://code.lds.org/nexus/content/groups/main-repo</url>
       </repository>
   </repositories>
 
 
   <dependencies>


       <dependency>
           <groupId>junit</groupId>
           <artifactId>junit</artifactId>
           <version>3.8.1</version>
           <scope>test</scope>
       </dependency>

       <!-- Hibernate Core -->
       <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
       <dependency>
           <groupId>org.hibernate</groupId>
           <artifactId>hibernate-core</artifactId>
           <version>5.2.2.Final</version>
       </dependency>


       <!-- MySQL JDBC driver -->
       <!-- http://mvnrepository.com/artifact/mysql/mysql-connector-java -->
       <dependency>
           <groupId>mysql</groupId>
           <artifactId>mysql-connector-java</artifactId>
           <version>5.1.34</version>
       </dependency>

       <!-- Oracle JDBC driver -->
       <dependency>
           <groupId>com.oracle</groupId>
           <artifactId>ojdbc6</artifactId>
           <version>11.2.0.3</version>
       </dependency>

       <!-- SQLServer JDBC driver (JTDS) -->
       <!-- http://mvnrepository.com/artifact/net.sourceforge.jtds/jtds -->
       <dependency>
           <groupId>net.sourceforge.jtds</groupId>
           <artifactId>jtds</artifactId>
           <version>1.3.1</version>
       </dependency>

   </dependencies>
 
</project>

3- Die Klasse Entity

Wir erstellen die Klasse Entity. Jede Entity bezeichnet eine Tabelle in DB. Meinen wir noch nicht die Klasse
  1. Department - die Abteilung
  2. Employee - Der Arbeitnehmer
  3. SalaryGrade - das Lohn niveau
  4. Timekeeper - der Zeitnehmer für Arbeitnehmer.
Department.java

package org.o7planning.tutorial.hibernate.entities;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.persistence.UniqueConstraint;

@Entity
@Table(name = "DEPARTMENT",
  uniqueConstraints = { @UniqueConstraint(columnNames = { "DEPT_NO" }) })
public class Department {

private Integer deptId;
private String deptNo;

private String deptName;
private String location;
private Set<Employee> employees = new HashSet<Employee>(0);

public Department() {
}

public Department(Integer deptId, String deptName, String location) {
   this.deptId = deptId;
   this.deptNo = "D" + this.deptId;
   this.deptName = deptName;
   this.location = location;
}

@Id
@Column(name = "DEPT_ID")
public Integer getDeptId() {
   return deptId;
}

public void setDeptId(Integer deptId) {
   this.deptId = deptId;
}

@Column(name = "DEPT_NO", length = 20, nullable = false)
public String getDeptNo() {
   return deptNo;
}

public void setDeptNo(String deptNo) {
   this.deptNo = deptNo;
}

@Column(name = "DEPT_NAME", nullable = false)
public String getDeptName() {
   return deptName;
}

public void setDeptName(String deptName) {
   this.deptName = deptName;
}

@Column(name = "LOCATION")
public String getLocation() {
   return location;
}

public void setLocation(String location) {
   this.location = location;
}

@OneToMany(fetch = FetchType.LAZY, mappedBy = "department")
public Set<Employee> getEmployees() {
   return employees;
}

public void setEmployees(Set<Employee> employees) {
   this.employees = employees;
}
}
Employee.java

package org.o7planning.tutorial.hibernate.entities;

import java.util.Date;
import java.util.HashSet;
import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.Lob;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.persistence.UniqueConstraint;

@Entity
@Table(name = "EMPLOYEE",
   uniqueConstraints = { @UniqueConstraint(columnNames = { "EMP_NO" }) })
public class Employee {
private Long empId;
private String empNo;

private String empName;
private String job;
private Employee manager;
private Date hideDate;
private Float salary;
private byte[] image;

private Department department;
private Set<Employee> employees = new HashSet<Employee>(0);

public Employee() {
}

public Employee(Long empId, String empName, String job, Employee manager,
        Date hideDate, Float salary, Float comm, Department department) {
    this.empId = empId;
    this.empNo = "E" + this.empId;
    this.empName = empName;
    this.job = job;
    this.manager = manager;
    this.hideDate = hideDate;
    this.salary = salary;
    this.department = department;
}

@Id
@Column(name = "EMP_ID")
public Long getEmpId() {
    return empId;
}

public void setEmpId(Long empId) {
    this.empId = empId;
}

@Column(name = "EMP_NO", length = 20, nullable = false)
public String getEmpNo() {
    return empNo;
}

public void setEmpNo(String empNo) {
    this.empNo = empNo;
}

@Column(name = "EMP_NAME", length = 50, nullable = false)
public String getEmpName() {
    return empName;
}

public void setEmpName(String empName) {
    this.empName = empName;
}

@Column(name = "JOB", length = 30, nullable = false)
public String getJob() {
    return job;
}

public void setJob(String job) {
    this.job = job;
}

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "MNG_ID")
public Employee getManager() {
    return manager;
}

public void setManager(Employee manager) {
    this.manager = manager;
}

@Column(name = "HIRE_DATE", nullable = false)
@Temporal(TemporalType.DATE)
public Date getHideDate() {
    return hideDate;
}

public void setHideDate(Date hideDate) {
    this.hideDate = hideDate;
}

@Column(name = "SALARY", nullable = false)
public Float getSalary() {
    return salary;
}

public void setSalary(Float salary) {
    this.salary = salary;
}

@Column(name = "IMAGE", length = 1111111, nullable = true)
@Lob
public byte[] getImage() {
    return image;
}

public void setImage(byte[] image) {
    this.image = image;
}

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "DEPT_ID", nullable = false)
public Department getDepartment() {
    return department;
}

public void setDepartment(Department department) {
    this.department = department;
}

@OneToMany(fetch = FetchType.LAZY, mappedBy = "empId")
public Set<Employee> getEmployees() {
    return employees;
}

public void setEmployees(Set<Employee> employees) {
    this.employees = employees;
}

}
SalaryGrade.java

package org.o7planning.tutorial.hibernate.entities;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "SALARY_GRADE")
public class SalaryGrade {
 private Integer grade;
 private Float lowSalary;
 private Float highSalary;

 public SalaryGrade() {
 }

 public SalaryGrade(Integer grade, Float lowSalary, Float highSalary) {
     this.grade = grade;
     this.lowSalary = lowSalary;
     this.highSalary = highSalary;
 }

 @Id
 @Column(name = "GRADE")
 public Integer getGrade() {
     return grade;
 }

 public void setGrade(Integer grade) {
     this.grade = grade;
 }

 @Column(name = "LOW_SALARY", nullable = false)
 public Float getLowSalary() {
     return lowSalary;
 }

 public void setLowSalary(Float lowSalary) {
     this.lowSalary = lowSalary;
 }

 @Column(name = "HIGH_SALARY", nullable = false)
 public Float getHighSalary() {
     return highSalary;
 }

 public void setHighSalary(Float highSalary) {
     this.highSalary = highSalary;
 }
}
Timekeeper.java

package org.o7planning.tutorial.hibernate.entities;

import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;

import org.hibernate.annotations.GenericGenerator;

@Entity
@Table(name = "TIMEKEEPER")
public class Timekeeper {
  public static final char IN = 'I';
  public static final char OUT = 'O';

  private String timekeeperId;

  private Date dateTime;

  private Employee employee;

  // 'I' or 'O'
  private char inOut;

  @Id
  @GeneratedValue(generator = "uuid")
  @GenericGenerator(name = "uuid", strategy = "uuid2")
  @Column(name = "Timekeeper_Id", length = 36)
  public String getTimekeeperId() {
      return timekeeperId;
  }

  public void setTimekeeperId(String timekeeperId) {
      this.timekeeperId = timekeeperId;
  }

  @Column(name = "Date_Time", nullable = false)
  @Temporal(TemporalType.TIMESTAMP)
  public Date getDateTime() {
      return dateTime;
  }

  public void setDateTime(Date dateTime) {
      this.dateTime = dateTime;
  }

  @ManyToOne(fetch = FetchType.LAZY)
  @JoinColumn(name = "EMP_ID", nullable = false)
  public Employee getEmployee() {
      return employee;
  }

  public void setEmployee(Employee employee) {
      this.employee = employee;
  }

  @Column(name = "In_Out", nullable = false, length = 1)
  public char getInOut() {
      return inOut;
  }

  public void setInOut(char inOut) {
      this.inOut = inOut;
  }

}

4- hibernate-xxx.cfg.xml

Zur Erstellung einer Tabelle sollen Sie eine Konfigurationsfile der Information database (hibernate-<datatype>.cfg.xml) und die Klasse Entity.
hibernate-oracle.cfg.xml

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
                            "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
   <session-factory>

       <property name="hibernate.dialect">org.hibernate.dialect.OracleDialect</property>
       <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
       <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:1521:db12c</property>
       <property name="hibernate.connection.username">simplehr2</property>
       <property name="hibernate.connection.password">12345</property>
       <property name="hibernate.show_sql">true</property>
       <property name="hibernate.connection.release_mode">auto</property>
       <property name="current_session_context_class">thread</property>
       <property name="hibernate.connection.autoReconnect">true</property>


       <mapping class="org.o7planning.tutorial.hibernate.entities.Department" />
       <mapping class="org.o7planning.tutorial.hibernate.entities.Employee" />
       <mapping class="org.o7planning.tutorial.hibernate.entities.SalaryGrade" />
       <mapping class="org.o7planning.tutorial.hibernate.entities.Timekeeper" />

   </session-factory>
 
</hibernate-configuration>
hibernate-mysql.cfg.xml

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
 
<hibernate-configuration>
<session-factory>
  <!-- Database connection settings -->
  <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
  <property name="connection.url">jdbc:mysql://tran-vmware:3306/simplehr?serverTimezone=UTC</property>
  <property name="connection.username">root</property>
  <property name="connection.password">1234</property>
 
  <!-- JDBC connection pool (use the built-in) -->
  <property name="connection.pool_size">1</property>
 
  <!-- SQL dialect -->
  <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
 
  <!-- Enable Hibernate's automatic session context management -->
  <property name="current_session_context_class">thread</property>
 
  <!-- Disable the second-level cache  -->
  <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>
 
  <!-- Echo all executed SQL to stdout -->
  <property name="show_sql">true</property>
 
   <mapping class="org.o7planning.tutorial.hibernate.entities.Department" />
   <mapping class="org.o7planning.tutorial.hibernate.entities.Employee" />
   <mapping class="org.o7planning.tutorial.hibernate.entities.SalaryGrade" />
   <mapping class="org.o7planning.tutorial.hibernate.entities.Timekeeper" />
 
</session-factory>

</hibernate-configuration>
hibernate-sqlserver.cfg.xml

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
      "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
      "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
 
<hibernate-configuration>
 <session-factory>
   <!-- Database connection settings -->
   <property name="connection.driver_class">net.sourceforge.jtds.jdbc.Driver</property>
   <property name="connection.url">jdbc:jtds:sqlserver://localhost:1433/simplehr;instance=SQLEXPRESS</property>
   <property name="connection.username">sa</property>
   <property name="connection.password">1234</property>
 
   <!-- JDBC connection pool (use the built-in) -->
   <property name="connection.pool_size">1</property>
 
   <!-- SQL dialect -->
   <property name="dialect">org.hibernate.dialect.SQLServerDialect</property>
 
   <!-- Enable Hibernate's automatic session context management -->
   <property name="current_session_context_class">thread</property>
 
   <!-- Disable the second-level cache  -->
   <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>
 
   <!-- Echo all executed SQL to stdout -->
   <property name="show_sql">true</property>
 
    <mapping class="org.o7planning.tutorial.hibernate.entities.Department" />
    <mapping class="org.o7planning.tutorial.hibernate.entities.Employee" />
    <mapping class="org.o7planning.tutorial.hibernate.entities.SalaryGrade" />
    <mapping class="org.o7planning.tutorial.hibernate.entities.Timekeeper" />
 
</session-factory>

</hibernate-configuration>
Stellen Sie sicher, dass Sie die leeren Schema erstellt haben (Die leeren database) hat keine Tabelle. Zum Beispiel: mit Oracle erstelle ich ein Schema mit dem Name vom simplehr2 

-- ORACLE
Create user simplehr2 identified by 12345;
grant dba to simplehr2;

5- Die Tabelle aus Entity erstellen

SchemaGeneratorDemo.java

package org.o7planning.generatetables;

import java.io.File;
import java.util.EnumSet;

import org.hibernate.boot.Metadata;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.hibernate.tool.schema.TargetType;

// Hibernate 5.
public class SchemaGeneratorDemo {

   public static final String SCRIPT_FILE = "exportScript.sql";

   private static SchemaExport getSchemaExport() {

       SchemaExport export = new SchemaExport();
       // Script file.
       File outputFile = new File(SCRIPT_FILE);
       String outputFilePath = outputFile.getAbsolutePath();

       System.out.println("Export file: " + outputFilePath);

       export.setDelimiter(";");
       export.setOutputFile(outputFilePath);
       
       // No Stop if Error
       export.setHaltOnError(false);
       //
       return export;
   }

   public static void dropDataBase(SchemaExport export, Metadata metadata) {
       // TargetType.DATABASE - Execute on Databse
       // TargetType.SCRIPT - Write Script file.
       // TargetType.STDOUT - Write log to Console.
       EnumSet<TargetType> targetTypes = EnumSet.of(TargetType.DATABASE, TargetType.SCRIPT, TargetType.STDOUT);

       export.drop(targetTypes, metadata);
   }

   public static void createDataBase(SchemaExport export, Metadata metadata) {
       // TargetType.DATABASE - Execute on Databse
       // TargetType.SCRIPT - Write Script file.
       // TargetType.STDOUT - Write log to Console.
 
       EnumSet<TargetType> targetTypes = EnumSet.of(TargetType.DATABASE, TargetType.SCRIPT, TargetType.STDOUT);

       SchemaExport.Action action = SchemaExport.Action.CREATE;
       //
       export.execute(targetTypes, action, metadata);

       System.out.println("Export OK");

   }

   public static void main(String[] args) {

       // Using Oracle Database.
 
       String configFileName = "hibernate-oracle.cfg.xml";

       // Create the ServiceRegistry from hibernate-xxx.cfg.xml
       ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()//
               .configure(configFileName).build();

       // Create a metadata sources using the specified service registry.
       Metadata metadata = new MetadataSources(serviceRegistry).getMetadataBuilder().build();

       SchemaExport export = getSchemaExport();

       System.out.println("Drop Database...");
       // Drop Database
       dropDataBase(export, metadata);

       System.out.println("Create Database...");
       // Create tables
       createDataBase(export, metadata);
   }
   
}
Das Beispiel durchführen
Sehen Sie die File Script:

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