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Hibernate操作Oarcle中Clob、Blob字段小结

阅读更多

   blog迁移至 :http://www.micmiu.com

 

最近常碰到有人问如何运用Hibernate操作Oracle中的Clob、Blob字段,相关问题大概如下几种:

  • 如何读、写数据库中的Clob、Blob字段?
  • 注释方式或者映射文件两种方式是如何实现的?
  • Clob字段是否可当成一般String来操作?
  • 为什么Clob字段插入正常,但是读取时却为null
  • JDBC的驱动是不是需要最新的,才能支持Clob当成String?
  • JDBC驱动不更新,有没有办法实现Clob当成String操作?
  • 。。。。。等等这些问题

下面我将以不同的实现方式的分别来演示,上述提到的问题答案将在具体的实例中给出详细的答案。本文目录:

  • [一]、Clob字段 - 注解方式的实现
  • [二]、Clob字段 - 映射文件的实现
  • [三]、Blob字段 - 注解方式的实现
  • [四]、Blob字段 - 映射文件的实现

     测试的相关源代码bigstring_oracle_src.7z

 

[一]、Clob字段 - 注解 方式的实现

 

   域对象:TbBigStrClob.java

package michael.hibernate.bigstring.oracle;

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

import org.hibernate.annotations.Type;

/**
 * 
 * @blog http://sjsky.iteye.com
 * @author Michael
 */
@Entity
@Table(name = "MY_TB_BIG_STR_CLOB")
public class TbBigStrClob {

    private Integer id;

    private String name;

    private String content;

    /**
     * @return the id
     */
    @Id
    @GeneratedValue
    @Column(name = "ID")
    public Integer getId() {
        return id;
    }

    /**
     * @return the name
     */
    @Column(name = "NAME", length = 20)
    public String getName() {
        return name;
    }

    /**
     * @return the content
     */
    @Lob
    //@Type(type = "text")
    @Column(name = "CONTENT", columnDefinition = "CLOB")
    public String getContent() {
        return content;
    }

    /**
     * @param pId the id to set
     */
    public void setId(Integer pId) {
        id = pId;
    }

    /**
     * @param pName the name to set
     */
    public void setName(String pName) {
        name = pName;
    }

    /**
     * @param pContent the content to set
     */
    public void setContent(String pContent) {
        content = pContent;
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return "TbBigStrClob :: id = [" + id + "],name = [" + name
                + "],content = [" + content + "].";
    }

}

 

   Hibernate 配置文件:hibernate.cfg.xml

 

<!DOCTYPE hibernate-configuration
    PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN"
    "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

	<session-factory>
		<property name="connection.driver_class">
			oracle.jdbc.driver.OracleDriver
		</property>
		<property name="connection.url">
			jdbc:oracle:thin:@192.168.8.49:1521:ora9i
		</property>
		<property name="connection.username">mytest</property>
		<property name="connection.password">123456</property>

		<property name="dialect">
			org.hibernate.dialect.Oracle9Dialect
		</property>

		<property name="connection.useUnicode">true</property>
		<property name="connection.characterEncoding">UTF-8</property>
		<property name="connection.SetBigStringTryClob">true</property>
		<property name="connection.pool_size">10</property>
		<property name="hibernate.jdbc.batch_size">10</property>


		<property name="show_sql">true</property>
		<property name="format_sql">false</property>
		<property name="current_session_context_class">thread</property>
		<property name="hbm2ddl.auto">update</property>

		<!-- 注释  -->
		<mapping
			class="michael.hibernate.bigstring.oracle.TbBigStrClob" />

	</session-factory>
</hibernate-configuration>
 

   测试程序:

package michael.hibernate.bigstring.oracle;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;

/**
 * 大字段Clob测试
 * @blog http://sjsky.iteye.com
 * @author Michael
 */
public class TestTbBigStr {

    /**
     * @param args
     */
    @SuppressWarnings("unchecked")
    public static void main(String[] args) {

        // 测试Hibernate 注释方法 操作 大字段 Clob
        TestTbBigStr.testClob();

    }

    /**
     * 测试Hibernate 注释方法 操作 大字段 Clob
     */
    @SuppressWarnings("unchecked")
    public static void testClob() {
        SessionFactory sessionFactory = null;
        Transaction ta = null;
        try {
            System.out.println("../../hibernate.cfg.xml configure");
            Configuration config = new AnnotationConfiguration()
                    .configure("michael/hibernate/bigstring/oracle/hibernate.cfg.xml");

            sessionFactory = config.buildSessionFactory();
            Session session = sessionFactory.getCurrentSession();
            String hsql = "select t from TbBigStrClob t ";
            System.out.println("start test clob ...");
            ta = session.beginTransaction();
            org.hibernate.Query query = session.createQuery(hsql);
            List<TbBigStrClob> list = query.list();
            if (list.size() == 0) {
                System.out.println("start to init clob data");
                List<TbBigStrClob> initlist = initClobData(5);
                for (TbBigStrClob po : initlist) {
                    session.save(po);
                }

                list = query.list();
            }
            System.out.println("query data list size = " + list.size());
            for (TbBigStrClob vo : list) {
                System.out.println(vo);
            }
            ta.commit();
        } catch (Exception e) {
            e.printStackTrace();
            ta.rollback();
        } finally {
            if (null != sessionFactory) {
                sessionFactory.close();
            }

        }
    }

    /**
     * 
     * @param dataSize
     * @return List
     */
    public static List<TbBigStrClob> initClobData(int dataSize) {
        List<TbBigStrClob> list = new ArrayList<TbBigStrClob>();
        for (int i = 1; i <= dataSize; i++) {
            TbBigStrClob vo = new TbBigStrClob();
            vo.setName("test_" + i);
            vo.setContent("我是大字段<Clob>,at date:" + new Date());
            list.add(vo);
        }
        return list;
    }

}

 运行结果:

../../hibernate.cfg.xml configure
start test clob ...
Hibernate: select tbbigstrcl0_.ID as ID2_, tbbigstrcl0_.NAME as NAME2_, tbbigstrcl0_.CONTENT as CONTENT2_ from MY_TB_BIG_STR_CLOB tbbigstrcl0_
start to init clob data
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: insert into MY_TB_BIG_STR_CLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_CLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_CLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_CLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_CLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: select tbbigstrcl0_.ID as ID2_, tbbigstrcl0_.NAME as NAME2_, tbbigstrcl0_.CONTENT as CONTENT2_ from MY_TB_BIG_STR_CLOB tbbigstrcl0_
query data list size = 5
TbBigStrClob :: id = [1813873],name = [test_1],content = [我是大字段<Clob>,at date:Mon Aug 22 13:10:38 CST 2011].
TbBigStrClob :: id = [1813874],name = [test_2],content = [我是大字段<Clob>,at date:Mon Aug 22 13:10:38 CST 2011].
TbBigStrClob :: id = [1813875],name = [test_3],content = [我是大字段<Clob>,at date:Mon Aug 22 13:10:38 CST 2011].
TbBigStrClob :: id = [1813876],name = [test_4],content = [我是大字段<Clob>,at date:Mon Aug 22 13:10:38 CST 2011].
TbBigStrClob :: id = [1813877],name = [test_5],content = [我是大字段<Clob>,at date:Mon Aug 22 13:10:38 CST 2011].

   运行结果可见:注解方式下,插入Clob数据和读取Clob数据均正常。

 

   Tips:

    1. 在Oracle10g + 10g驱动(或者Oracle11g + 11g驱动)的环境下,只需要在Clob字段上,增加注解@Column(name = "CONTENT", columnDefinition = "CLOB"),即可成功实现建表、Clob字段的读写操作。

    2. 在Oracle9i+9i的驱动环境下,仅增加注释@Column(name = "CONTENT", columnDefinition = "CLOB")时,建表、写人数据均能正常,但读取时会显示数据为空。如果在Oracle9i下又必须用9i的驱动,可以在Clob字段中再增加一行注解@Lob 或者 @Type(type = "text")。(运用spring中org.springframework.jdbc.support.lob.OracleLobHandler,这个没有具体实践过,就不在本文展开了

    3. 在Oracle9i+10g的驱动环境下,增加注解@Column(name = "CONTENT", columnDefinition = "CLOB"),同样可以成功实现建表、Clob字段的读写操作,可见9i的驱动对Clob支持不是很好,但10g、11g已经做了更新。

 


[二]、Clob字段 - 映射文件的实现

 

   bean文件:BigStrClob.java

package michael.hibernate.bigstring.oracle;

/**
 * 
 * @blog http://sjsky.iteye.com
 * @author Michael
 */

public class BigStrClob {

    private Integer id;

    private String name;

    private String content;

    /**
     * @return the id
     */
    public Integer getId() {
        return id;
    }

    /**
     * @return the name
     */
    public String getName() {
        return name;
    }

    /**
     * @return the content
     */
    public String getContent() {
        return content;
    }

    /**
     * @param pId the id to set
     */
    public void setId(Integer pId) {
        id = pId;
    }

    /**
     * @param pName the name to set
     */
    public void setName(String pName) {
        name = pName;
    }

    /**
     * @param pContent the content to set
     */
    public void setContent(String pContent) {
        content = pContent;
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return "BigStrClob :: id = [" + id + "],name = [" + name
                + "],content = [" + content + "].";
    }

}
 

   映射文件:tb_bigstr.hb.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
	"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="michael.hibernate.bigstring.oracle">

	<class name="BigStrClob" table="MY_HB_BIG_STR_CLOB">

		<id name="id" type="int" unsaved-value="null">
			<generator class="increment" />
		</id>

		<property name="name" column="NAME" type="string"
			not-null="false" length="20" />

		<property name="content" column="CONTENT" type="text"
			not-null="false" />

	</class>

</hibernate-mapping>

 

  在hibernate.cfg.xml文件中增加域对象的映射文件:

<!-- 映射 -->
		<mapping
			resource="michael/hibernate/bigstring/oracle/tb_bigstr.hb.xml" />

 

   测试程序:

package michael.hibernate.bigstring.oracle;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;

/**
 * 大字段Clob测试
 * @blog http://sjsky.iteye.com
 * @author Michael
 */
public class TestHbBigStr {

    /**
     * @param args
     */

    public static void main(String[] args) {

        // 测试Hibernate 映射文件 操作 大字段 Clob
        TestHbBigStr.testClob();
    }

    /**
     * 测试Hibernate 映射文件 操作 大字段 Clob
     */
    @SuppressWarnings("unchecked")
    public static void testClob() {
        SessionFactory sessionFactory = null;
        Transaction ta = null;
        try {
            System.out.println("../../hibernate.cfg.xml configure");
            Configuration config = new AnnotationConfiguration()
                    .configure("michael/hibernate/bigstring/oracle/hibernate.cfg.xml");

            sessionFactory = config.buildSessionFactory();
            Session session = sessionFactory.getCurrentSession();
            String hsql = "select t from BigStrClob t ";
            ta = session.beginTransaction();
            org.hibernate.Query query = session.createQuery(hsql);
            List<BigStrClob> list = query.list();
            if (list.size() == 0) {
                System.out.println("start to init clob data");
                List<BigStrClob> initlist = initClobData(5);
                for (BigStrClob po : initlist) {
                    session.save(po);
                }
                list = query.list();
            }
            System.out.println("Query data list size = " + list.size());
            for (BigStrClob vo : list) {
                System.out.println(vo);
            }

            ta.commit();
        } catch (Exception e) {
            e.printStackTrace();
            ta.rollback();
        } finally {
            if (null != sessionFactory) {
                sessionFactory.close();
            }

        }
    }

    /**
     * 
     * @param dataSize
     * @return List
     */
    public static List<BigStrClob> initClobData(int dataSize) {
        List<BigStrClob> list = new ArrayList<BigStrClob>();
        for (int i = 1; i <= dataSize; i++) {
            BigStrClob vo = new BigStrClob();
            vo.setName("test_" + i);
            vo.setContent("我是大字段<Clob>,at date:" + new Date());
            list.add(vo);
        }
        return list;
    }

}

 

   运行结果如下:

../../hibernate.cfg.xml configure
Hibernate: select bigstrblob0_.id as id1_, bigstrblob0_.NAME as NAME1_, bigstrblob0_.CONTENT as CONTENT1_ from MY_HB_BIG_STR_BLOB bigstrblob0_
start to init blob data
Hibernate: select max(id) from MY_HB_BIG_STR_BLOB
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: select bigstrblob0_.id as id1_, bigstrblob0_.NAME as NAME1_, bigstrblob0_.CONTENT as CONTENT1_ from MY_HB_BIG_STR_BLOB bigstrblob0_
Query data list size = 5
BigStrBlob :: id = [1],name = [test_1],content = [我是大字段<Blob>,at date:Mon Aug 22 13:28:51 CST 2011].
BigStrBlob :: id = [2],name = [test_2],content = [我是大字段<Blob>,at date:Mon Aug 22 13:28:51 CST 2011].
BigStrBlob :: id = [3],name = [test_3],content = [我是大字段<Blob>,at date:Mon Aug 22 13:28:51 CST 2011].
BigStrBlob :: id = [4],name = [test_4],content = [我是大字段<Blob>,at date:Mon Aug 22 13:28:51 CST 2011].
BigStrBlob :: id = [5],name = [test_5],content = [我是大字段<Blob>,at date:Mon Aug 22 13:28:51 CST 2011].

   从运行结果可见:映射文件的方式下,插入Clob数据和读取Clob数据均正常

 

     Tips: 如果是映射文件的,只需要把Clob字段的类型指定为text即:type="text"


[三]、Blob字段 - 注解 方式的实现

 

域对象的文件:TbBigStrBlob.java

package michael.hibernate.bigstring.oracle;

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

/**
 * 
 * @blog http://sjsky.iteye.com
 * @author Michael
 */
@Entity
@Table(name = "MY_TB_BIG_STR_BLOB")
public class TbBigStrBlob {

    private Integer id;

    private String name;

    private byte[] content;

    /**
     * @return the id
     */
    @Id
    @GeneratedValue
    @Column(name = "ID")
    public Integer getId() {
        return id;
    }

    /**
     * @return the name
     */
    @Column(name = "NAME", length = 20)
    public String getName() {
        return name;
    }

    /**
     * @return the content
     */
    @Lob
    @Column(name = "CONTENT", columnDefinition = "BLOB")
    public byte[] getContent() {
        return content;
    }

    /**
     * @param pId the id to set
     */
    public void setId(Integer pId) {
        id = pId;
    }

    /**
     * @param pName the name to set
     */
    public void setName(String pName) {
        name = pName;
    }

    /**
     * @param pContent the content to set
     */
    public void setContent(byte[] pContent) {
        content = pContent;
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return "TbBigStrBlob :: id = [" + id + "],name = [" + name
                + "],content = [" + new String(content) + "].";
    }

}

 

   在hibernate.cfg.xml中增加域对象:

<mapping  class="michael.hibernate.bigstring.oracle.TbBigStrBlob" />

   运行测试程序:

package michael.hibernate.bigstring.oracle;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;

/**
 * 大字段Clob测试
 * @blog http://sjsky.iteye.com
 * @author Michael
 */
public class TestTbBigStr {

    /**
     * @param args
     */
    @SuppressWarnings("unchecked")
    public static void main(String[] args) {
        // 测试Hibernate 注释方法 操作 大字段 Blob
        TestTbBigStr.testBlob();
    }

    /**
     * 测试Hibernate 注释方法 操作 大字段 Blob
     */
    @SuppressWarnings("unchecked")
    public static void testBlob() {
        SessionFactory sessionFactory = null;
        Transaction ta = null;
        try {
            System.out.println("../../hibernate.cfg.xml configure");
            Configuration config = new AnnotationConfiguration()
                    .configure("michael/hibernate/bigstring/oracle/hibernate.cfg.xml");

            sessionFactory = config.buildSessionFactory();
            Session session = sessionFactory.getCurrentSession();
            String hsql = "select t from TbBigStrBlob t ";
            System.out.println("start test clob ...");
            ta = session.beginTransaction();
            org.hibernate.Query query = session.createQuery(hsql);
            List<TbBigStrBlob> list = query.list();
            if (list.size() == 0) {
                System.out.println("start to init blob data");
                List<TbBigStrBlob> initlist = initBlobData(5);
                for (TbBigStrBlob po : initlist) {
                    session.save(po);
                }

                list = query.list();
            }
            System.out.println("query data list size = " + list.size());
            for (TbBigStrBlob vo : list) {
                System.out.println(vo);
            }
            ta.commit();
        } catch (Exception e) {
            e.printStackTrace();
            ta.rollback();
        } finally {
            if (null != sessionFactory) {
                sessionFactory.close();
            }

        }
    }

    /**
     * 
     * @param dataSize
     * @return List
     */
    public static List<TbBigStrBlob> initBlobData(int dataSize) {
        List<TbBigStrBlob> list = new ArrayList<TbBigStrBlob>();
        for (int i = 1; i <= dataSize; i++) {
            TbBigStrBlob vo = new TbBigStrBlob();
            vo.setName("test_" + i);
            vo.setContent(("我是大字段<Blob>,at date:" + new Date()).getBytes());
            list.add(vo);
        }
        return list;
    }
}

 

运行结果如下:

../../hibernate.cfg.xml configure
start test clob ...
Hibernate: select tbbigstrbl0_.ID as ID3_, tbbigstrbl0_.NAME as NAME3_, tbbigstrbl0_.CONTENT as CONTENT3_ from MY_TB_BIG_STR_BLOB tbbigstrbl0_
start to init blob data
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: select hibernate_sequence.nextval from dual
Hibernate: insert into MY_TB_BIG_STR_BLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_BLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_BLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_BLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: insert into MY_TB_BIG_STR_BLOB (NAME, CONTENT, ID) values (?, ?, ?)
Hibernate: select tbbigstrbl0_.ID as ID3_, tbbigstrbl0_.NAME as NAME3_, tbbigstrbl0_.CONTENT as CONTENT3_ from MY_TB_BIG_STR_BLOB tbbigstrbl0_
query data list size = 5
TbBigStrBlob :: id = [1813878],name = [test_1],content = [我是大字段<Blob>,at date:Mon Aug 22 13:40:56 CST 2011].
TbBigStrBlob :: id = [1813879],name = [test_2],content = [我是大字段<Blob>,at date:Mon Aug 22 13:40:56 CST 2011].
TbBigStrBlob :: id = [1813880],name = [test_3],content = [我是大字段<Blob>,at date:Mon Aug 22 13:40:56 CST 2011].
TbBigStrBlob :: id = [1813881],name = [test_4],content = [我是大字段<Blob>,at date:Mon Aug 22 13:40:56 CST 2011].
TbBigStrBlob :: id = [1813882],name = [test_5],content = [我是大字段<Blob>,at date:Mon Aug 22 13:40:56 CST 2011].

   从运行结果可见:注解的方式下,插入Blob数据和读取Blob数据均正常

 

   Tips: 对于byte[] 类型的字段如果要映射成Blob字段,只需要在该字段增加如下注解即可:

@Lob
@Column(name = "CONTENT", columnDefinition = "BLOB")


[四]、Blob字段 - 映射文件的实现

 映射文件对象:BigStrBlob.java

package michael.hibernate.bigstring.oracle;

/**
 * 
 * @blog http://sjsky.iteye.com
 * @author Michael
 */

public class BigStrBlob {

    private Integer id;

    private String name;

    private byte[] content;

    /**
     * @return the id
     */
    public Integer getId() {
        return id;
    }

    /**
     * @return the name
     */
    public String getName() {
        return name;
    }

    /**
     * @return the content
     */
    public byte[] getContent() {
        return content;
    }

    /**
     * @param pId the id to set
     */
    public void setId(Integer pId) {
        id = pId;
    }

    /**
     * @param pName the name to set
     */
    public void setName(String pName) {
        name = pName;
    }

    /**
     * @param pContent the content to set
     */
    public void setContent(byte[] pContent) {
        content = pContent;
    }

    /*
     * (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return "BigStrBlob :: id = [" + id + "],name = [" + name
                + "],content = [" + new String(content) + "].";
    }

}

映射文件:tb_bigstr.hb.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
	"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="michael.hibernate.bigstring.oracle">

	<class name="BigStrBlob" table="MY_HB_BIG_STR_BLOB">

		<id name="id" type="int" unsaved-value="null">
			<generator class="increment" />
		</id>

		<property name="name" column="NAME" type="string"
			not-null="false" length="20" />

		<property name="content" column="CONTENT" type="binary"
			not-null="false" />

	</class>

</hibernate-mapping>

   测试程序:

package michael.hibernate.bigstring.oracle;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;

/**
 * 大字段Clob测试
 * @blog http://sjsky.iteye.com
 * @author Michael
 */
public class TestHbBigStr {

    /**
     * @param args
     */

    public static void main(String[] args) {
        // 测试Hibernate 映射文件 操作 大字段 Blob
        TestHbBigStr.testBlob();
    }

    /**
     * 测试Hibernate 映射文件 操作 大字段 Clob
     */
    @SuppressWarnings("unchecked")
    public static void testBlob() {
        SessionFactory sessionFactory = null;
        Transaction ta = null;
        try {
            System.out.println("../../hibernate.cfg.xml configure");
            Configuration config = new AnnotationConfiguration()
                    .configure("michael/hibernate/bigstring/oracle/hibernate.cfg.xml");

            sessionFactory = config.buildSessionFactory();
            Session session = sessionFactory.getCurrentSession();
            String hsql = "select t from BigStrBlob t ";
            ta = session.beginTransaction();
            org.hibernate.Query query = session.createQuery(hsql);
            List<BigStrBlob> list = query.list();
            if (list.size() == 0) {
                System.out.println("start to init blob data");
                List<BigStrBlob> initlist = initBlobData(5);
                for (BigStrBlob po : initlist) {
                    session.save(po);
                }
                list = query.list();
            }
            System.out.println("Query data list size = " + list.size());
            for (BigStrBlob vo : list) {
                System.out.println(vo);
            }

            ta.commit();
        } catch (Exception e) {
            e.printStackTrace();
            ta.rollback();
        } finally {
            if (null != sessionFactory) {
                sessionFactory.close();
            }

        }
    }

    /**
     * 
     * @param dataSize
     * @return List
     */
    public static List<BigStrBlob> initBlobData(int dataSize) {
        List<BigStrBlob> list = new ArrayList<BigStrBlob>();
        for (int i = 1; i <= dataSize; i++) {
            BigStrBlob vo = new BigStrBlob();
            vo.setName("test_" + i);
            vo.setContent(("我是大字段<Blob>,at date:" + new Date()).getBytes());
            list.add(vo);
        }
        return list;
    }

}

   运行结果如下:

../../hibernate.cfg.xml configure
Hibernate: select bigstrblob0_.id as id1_, bigstrblob0_.NAME as NAME1_, bigstrblob0_.CONTENT as CONTENT1_ from MY_HB_BIG_STR_BLOB bigstrblob0_
start to init blob data
Hibernate: select max(id) from MY_HB_BIG_STR_BLOB
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: insert into MY_HB_BIG_STR_BLOB (NAME, CONTENT, id) values (?, ?, ?)
Hibernate: select bigstrblob0_.id as id1_, bigstrblob0_.NAME as NAME1_, bigstrblob0_.CONTENT as CONTENT1_ from MY_HB_BIG_STR_BLOB bigstrblob0_
Query data list size = 5
BigStrBlob :: id = [1],name = [test_1],content = [我是大字段<Blob>,at date:Mon Aug 22 13:47:50 CST 2011].
BigStrBlob :: id = [2],name = [test_2],content = [我是大字段<Blob>,at date:Mon Aug 22 13:47:50 CST 2011].
BigStrBlob :: id = [3],name = [test_3],content = [我是大字段<Blob>,at date:Mon Aug 22 13:47:50 CST 2011].
BigStrBlob :: id = [4],name = [test_4],content = [我是大字段<Blob>,at date:Mon Aug 22 13:47:50 CST 2011].
BigStrBlob :: id = [5],name = [test_5],content = [我是大字段<Blob>,at date:Mon Aug 22 13:47:50 CST 2011].

    从运行结果可见:映射文件的方式下,插入Blob数据和读取Blob数据均正常

 

    Tips: 对于是映射文件的方式,Blob字段的类型指定为binary即:type=" binary "

 

 

 

本文连接:http://sjsky.iteye.com/blog/1154916

 

 

转载请注明来自:Michael's blog @ http://sjsky.iteye.com

----------------------------- 分 ------------------------------ 隔 ------------------------------ 线 ------------------------------

 

 

 

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4 楼 fengqing90 2013-09-17  
//@Type(type = "text")
//@Type(type="org.springframework.orm.hibernate3.support.ClobStringType")
//@Type(type="org.hibernate.type.ClobType")
@Column(name = "DATA_INFO", columnDefinition = "CLOB") 
太给力了,找了半天用了上面的3种实现均有问题,最后用columnDefinition = "CLOB" 轻松解决了。
3 楼 draem0507 2013-08-23  
字节肯定有长度限制
可以通过SerializableBlob平滑的从java.sql.Blob过度到oracle.sql.BLOB

SerializableBlob blob = (SerializableBlob) lazy2.getBlobname();
            java.sql.Blob wrapBlob = blob.getWrappedBlob();
            BLOB tmpBlob = (BLOB) wrapBlob;
//流读写
//重刷缓存 提交
2 楼 sjsky 2011-12-26  
gzcsschen 写道
你这个对小于4000的没问题
大了就会出问题


这个我有时间测试下的 ,奇怪了
1 楼 gzcsschen 2011-12-22  
你这个对小于4000的没问题
大了就会出问题

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