Map Serializable Entity To Lob : Clob Blob « JPA « Java Tutorial

1. Java Tutorial
2. JPA
3. Clob Blob

File: Customer.java

import javax.persistence.*;

import java.util.Date;

@Entity

public class Customer implements java.io.Serializable 
{
   private int id;
   private JPEG picture;
   
   @Id
   @GeneratedValue

   public int getId()
   {
      return id;
   }
   public void setId(int pk) 
   {
      id = pk;
   }


   @Lob @Basic(fetch=FetchType.LAZY)
   public JPEG getPicture() { return picture; }
   public void setPicture(JPEG jpeg) { picture = jpeg; }
}

File: JPEG.java

public class JPEG implements java.io.Serializable
{
   public JPEG() {}
}

File: Helper.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");
        }
      }
    }
  }
}

File: Main.java

import java.util.List;

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();




    em.getTransaction().commit();
    em.close();
    emf.close();

    Helper.checkData();
  }
}

File: persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>

22.24.Clob Blob
	22.24.1.	Mark String As Lob
	22.24.2.	Mark Byte Array Field As Lob
	22.24.3.	Mark Abstract Entity With Mapped Superclass
	22.24.4.	Map Serializable Entity To Lob
	22.24.5.	Java Byte Array Lob Mapped To Long VarBinary