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bboss persistent 1.0.2中方便地实现大字段(clob,blob)的处理

程序员文章站 2022-03-31 15:28:02
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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: