Hibernate操作Oracle中clob、blob总结

一、区别与定义
LONG: 可变长的字符串数据，最长2G，LONG具有VARCHAR2列的特性，可以存储长文本一个表中最多一个LONG列
LONG RAW: 可变长二进制数据，最长2G
CLOB:  字符大对象Clob 用来存储单字节的字符数据
NCLOB: 用来存储多字节的字符数据
BLOB: 用于存储二进制数据
BFILE: 存储在文件中的二进制数据，这个文件中的数据只能被只读访。但该文件不包含在数据库内。
bfile字段实际的文件存储在文件系统中,字段中存储的是文件定位指针.bfile对oracle来说是只读的,也不参与事务性控制和数据恢复。
二、clob、blob实现方式
1、 Clob字段 - 注解方式的实现
2、 Clob字段 - 映射文件的实现
3、 Blob字段 - 注解方式的实现
4、 Blob字段 - 映射文件的实现


1、 Clob字段 - 注解方式的实现

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;  
    }  
  
}  

提示:
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")。（[color=blue]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。[/color]
2、 Clob字段 - 映射文件的实现
Bean文件:

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：

 <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;  
    }  
  
}

提示:
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"。

3、Blob字段 - 注解 方式的实现

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;  
    }  
}  

提示:
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")  

4、Blob字段 - 映射文件的实现
bean文件

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;  
    }  
  
}  

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



本文转自：http://sjsky.iteye.com/blog/1154916