bboss persistent 1.0.2中方便地实现大字段(clob,blob)的处理
bboss项目下载列表 在sourceforge访问地址为：
https://sourceforge.net/project/showfiles.php?group_id=238653
bboss-persistent 1.0.2 下载地址
http://sourceforge.net/project/platformdownload.php?group_id=238653
bboss persistent框架提供了对大字段处理的封装，本文详细介绍具体的用法：
1.获取与blob和clob字段相关的流对象
2.直接获取操作lob字段包括增删改查4种操作，其中有通用的操作（适用于所有的数据库），针对oracle的操作方法。
下面详细介绍
获取与blob和clob字段相关的流对象
package com.frameworkset.common;
import java.sql.SQLException;
import com.frameworkset.common.poolman.DBUtil;
import com.frameworkset.common.poolman.PreparedDBUtil;
import com.frameworkset.common.poolman.handle.ValueExchange;
/**
* 测试如下方法是否正常工作
* dbUtil.getBinaryStream
* dbUtil.getUnicodeStream(
* dbUtil.getAsciiStream(
* getCharacterStream(
* <p>Title: TestStream.java</p>
*
* <p>Description: </p>
*
* <p>Copyright: Copyright (c) 2007</p>
* @Date Dec 5, 2008 3:12:22 PM
* @author biaoping.yin
* @version 1.0.1
*/
public class TestStream {
public static void testClob()
{
DBUtil dbUtil = new DBUtil();
try {
dbUtil.executeSelect("select clobname from test where id='0'");
System.out.println("BinaryStream:" + ValueExchange.getStringFromStream(dbUtil.getBinaryStream(0, 0)));
System.out.println("UnicodeStream:" + ValueExchange.getStringFromStream(dbUtil.getUnicodeStream(0, 0)));
System.out.println("AsciiStream:" + ValueExchange.getStringFromStream(dbUtil.getAsciiStream(0, 0)));
System.out.println("Reader:" + ValueExchange.getStringFromReader(dbUtil.getCharacterStream(0, 0)));
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void testBlob()
{
PreparedDBUtil pdb = new PreparedDBUtil();
DBUtil dbUtil = new DBUtil();
try {
pdb.preparedUpdate("update test set blobname = ? where id = '0'");
pdb.setBlob(1, "blob".getBytes());
pdb.executePrepared();
dbUtil.executeSelect("select blobname from test where id='0'");
System.out.println("BinaryStream:" + ValueExchange.getStringFromStream(dbUtil.getBinaryStream(0, 0)));
System.out.println("UnicodeStream:" + ValueExchange.getStringFromStream(dbUtil.getUnicodeStream(0, 0)));
System.out.println("AsciiStream:" + ValueExchange.getStringFromStream(dbUtil.getAsciiStream(0, 0)));
/**
* blob类型的字段不能直接转换为Reader对象
*/
System.out.println("Reader:" + ValueExchange.getStringFromReader(dbUtil.getCharacterStream(0, 0)));
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void main(String[] args)
{
testBlob();
}
}
直接获取操作lob字段包括增删改查4种操作，其中有通用的操作（适用于所有的数据库）和针对oracle的操作方法
/*
* Copyright 2008 biaoping.yin
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.frameworkset.common;
import javax.transaction.RollbackException;
import oracle.sql.BLOB;
import oracle.sql.CLOB;
import com.frameworkset.common.poolman.DBUtil;
import com.frameworkset.common.poolman.PreparedDBUtil;
import com.frameworkset.orm.transaction.TransactionManager;
/**
*
* <p>Title: TestLob.java</p>
*
* <p>
* Description:运行本类时必须下载 bboss persistent 框架的version 1.0.2 下载的地址如下：
* https://sourceforge.net/project/showfiles.php?group_id=238653
* </p>
*
* <p>Copyright: Copyright (c) 2007</p>
* @Date Dec 24, 2008 10:05:04 PM
* @author biaoping.yin
* @version 1.0
*/
public class TestLob {
/**
* 第一种插入blob字段的方法，通用的处理模式，适用于所有类型的数据库
*/
public static void testBlobWrite(String id)
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
try {
dbUtil.preparedInsert( "insert into test(id,blobname) values(?,?)");
dbUtil.setString(1, id);
dbUtil.setBlob(2, new java.io.File("d:/内容管理系统升级步骤.txt"));//直接将文件存储到大字段中
dbUtil.executePrepared();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally
{
}
}
/**
* 针对oracle Blob字段的插入操作
*/
public static void testBigBlobWrite()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
TransactionManager tm = new TransactionManager();
try {
//启动事务
tm.begin();
//先插入一条记录,blob字段初始化为empty_lob
dbUtil.preparedInsert( "insert into test(id,blobname) values(?,?)");
String id = DBUtil.getNextStringPrimaryKey("test");
dbUtil.setString(1, id);
dbUtil.setBlob(2,BLOB.empty_lob());//先设置空的blob字段
dbUtil.executePrepared();
//查找刚才的插入的记录，修改blob字段的值为一个文件
dbUtil = new PreparedDBUtil();
dbUtil.preparedSelect("select blobname from test where id = ?");
dbUtil.setString(1, id);
dbUtil.executePrepared();
BLOB blob = (BLOB)dbUtil.getBlob(0, "blobname");
if(blob != null)
{
DBUtil.updateBLOB(blob, new java.io.File("d:/wls_docs92.chm"));
}
tm.commit();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
try {
tm.rollback();
} catch (RollbackException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
finally
{
tm = null;
dbUtil = null;
}
}
/**
* 第一种update blob字段的方法，通用的处理模式，适用于所有类型的数据库
*/
public static void testBlobUpdate()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
try {
dbUtil.preparedUpdate("update test set blobname= ? where id= ?");
dbUtil.setString(2, "12");
dbUtil.setBlob(1, new java.io.File("d:/readme.txt"));//直接将文件存储到大字段中
dbUtil.executePrepared();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally
{
dbUtil = null;
}
}
/**
* 针对oracle Blob字段的update操作
*/
public static void testBigBlobUpdate()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
TransactionManager tm = new TransactionManager();
try {
//启动事务
tm.begin();
//先查询id=12一条记录,以乐观锁的方式来处理这条记录，当有其他程序正在修改id=12的记录时，将抛出异常直接终止改修改操作
dbUtil.preparedSelect( "select id,blobname from test where id = ? for update nowait");
String id = "12";
dbUtil.setString(1, id);
dbUtil.executePrepared();
BLOB blob = (BLOB)dbUtil.getBlob(0, "blobname");
if(blob != null)
{
//更新blob字段的值
DBUtil.updateBLOB(blob, new java.io.File("d:/readme.txt"));
}
//提交事务
tm.commit();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
try {
//回滚事务
tm.rollback();
} catch (RollbackException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
finally
{
tm = null;
dbUtil = null;
}
}
/**
* 大字段的读取
*/
public static void testBlobRead()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
try {
//查询大字段内容并且将大字段存放到文件中
dbUtil.preparedSelect( "select id,blobname from test");
dbUtil.executePrepared();
for(int i = 0; i < dbUtil.size(); i ++)
{
dbUtil.getFile(i, "blobname", new java.io.File("d:/wls_docs921.chm"));//将blob字段的值转换为文件
// Blob blob = dbUtil.getBlob(i, "blobname");//获取blob字段的值到blob变量中。
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally
{
}
}
/**
* clob字段的写入
*/
public static void testClobWrite(String id)
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
try {
dbUtil.preparedInsert( "insert into test(id,clobname) values(?,?)");
// dbUtil.setString(1, DBUtil.getNextStringPrimaryKey("test"));
dbUtil.setString(1, id);
dbUtil.setClob(2,"clobvalue");//直接将字符串存储到clob字段中，也可以直接使用dbUtil.setString(2,"clobvalue")来设置clob字段的值
dbUtil.executePrepared();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally
{
}
}
/**
* 针对oracle Clob字段的插入操作
*/
public static void testBigClobWrite()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
TransactionManager tm = new TransactionManager();
try {
//启动事务
tm.begin();
//先插入一条记录,blob字段初始化为empty_lob
dbUtil.preparedInsert( "insert into test(id,clobname) values(?,?)");
String id = DBUtil.getNextStringPrimaryKey("test");
dbUtil.setString(1, id);
dbUtil.setClob(2,CLOB.empty_lob());//先设置空的blob字段
dbUtil.executePrepared();
//查找刚才的插入的记录，修改blob字段的值为一个文件
dbUtil = new PreparedDBUtil();
dbUtil.preparedSelect("select clobname from test where id = ?");
dbUtil.setString(1, id);
dbUtil.executePrepared();
CLOB clob = (CLOB)dbUtil.getClob(0, "clobname");
if(clob != null)
{
DBUtil.updateCLOB(clob, new java.io.File("d:\\route.txt"));
}
tm.commit();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
try {
tm.rollback();
} catch (RollbackException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
finally
{
tm = null;
dbUtil = null;
}
}
/**
* clob字段的更新
*/
public static void testClobUpdate()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
try {
dbUtil.preparedUpdate( "update test set clobname=? where id='12'");
dbUtil.setClob(1,"clobvalue11111");//直接将字符串存储到clob字段中，也可以直接使用dbUtil.setString(2,"clobvalue")来设置clob字段的值
dbUtil.executePrepared();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally
{
}
}
/**
* 针对oracle Clob字段的修改操作
*/
public static void testBigClobUpdate()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
TransactionManager tm = new TransactionManager();
try {
//启动事务
tm.begin();
//先插入一条记录,blob字段初始化为empty_lob
dbUtil.preparedSelect( "select id,clobname from test where id='12' for update nowait");
dbUtil.executePrepared();
CLOB clob = (CLOB)dbUtil.getClob(0, "clobname");
if(clob != null)
{
DBUtil.updateCLOB(clob, new java.io.File("d:\\readme.txt"));
}
tm.commit();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
try {
tm.rollback();
} catch (RollbackException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
finally
{
tm = null;
dbUtil = null;
}
}
/**
* clob字段的读取
*/
public static void testClobRead()
{
PreparedDBUtil dbUtil = new PreparedDBUtil();
try {
//查询大字段内容并且将大字段存放到文件中
dbUtil.preparedSelect( "select id,clobname from test");
dbUtil.executePrepared();
for(int i = 0; i < dbUtil.size(); i ++)
{
dbUtil.getFile(i, "clobname", new java.io.File("d:/route" + i + ".txt")); //读取clob字段到文件中
// String clobvalue = dbUtil.getString(i, "clobname");//获取clob字段到字符串变量中
// Clob clob = dbUtil.getClob(i, "clobname");//获取clob字段值到clob类型变量中
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally
{
dbUtil = null;
}
}
public static void main(String[] args)
{
System.out.print("start.........");
DBUtil.debugMemory();
for(int i = 0; i < 1; i ++)
{
// String id = DBUtil.getNextStringPrimaryKey("test");
String id = "12";
// testBlobWrite(id);
testClobWrite( id);
// testBigBlobWrite();
// testClobWrite();
// testBigClobWrite();
}
// TestLob.testClobUpdate();
testBigClobUpdate();
// TestLob.testBlobUpdate();
// TestLob.testBigBlobUpdate();
// testBlobWrite();
// testBigBlobWrite();
// DBUtil.debugMemory();
// testBlobRead();
// testClobRead();
System.out.println("end.........");
DBUtil.debugMemory();
}
}
运行上述的测试示例，需要在数据库中执行以下脚本，脚本已经在oracle 10上测试通过：
drop table test;
CREATE TABLE TEST
(
NAME VARCHAR2(4000),
ID VARCHAR2(100)
);
drop table test1;
CREATE TABLE TEST1
(
A VARCHAR2(12)
);
DROP SEQUENCE SEQ_TEST;
CREATE SEQUENCE SEQ_TEST
START WITH 160
MAXVALUE 999999999999999999999999999
MINVALUE 0
NOCYCLE
CACHE 20
NOORDER;
drop table TABLEINFO cascade constraints
/
CREATE TABLE TABLEINFO
(
TABLE_NAME VARCHAR2(255) NOT NULL,
TABLE_ID_NAME VARCHAR2(255),
TABLE_ID_INCREMENT NUMBER(5) DEFAULT 1,
TABLE_ID_VALUE NUMBER(20) DEFAULT 0,
TABLE_ID_GENERATOR VARCHAR2(255),
TABLE_ID_TYPE VARCHAR2(255),
TABLE_ID_PREFIX VARCHAR2(255)
);
COMMENT ON TABLE TABLEINFO IS '表信息维护对象';
COMMENT ON COLUMN TABLEINFO.TABLE_NAME IS '表名称';
COMMENT ON COLUMN TABLEINFO.TABLE_ID_NAME IS '表的主键名称';
COMMENT ON COLUMN TABLEINFO.TABLE_ID_INCREMENT IS '表的主键递增量
缺省为1';
COMMENT ON COLUMN TABLEINFO.TABLE_ID_VALUE IS '主键当前值：缺省为0';
COMMENT ON COLUMN TABLEINFO.TABLE_ID_GENERATOR IS '自定义表主键生成机制
必需从
com.frameworkset.common.poolman.sql.PrimaryKey集成';
由于脚本太长，请下载附件：