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展示JDBC存取ORACLE大型数据对象LOB几种情况的示范类

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;展示JDBC存取Oracle大型数据对象LOB几种情况的示范类 import Java.io.*;
import java.util.*;
import java.sql.*; public class LobPros
{ ;/**
* ORACLE驱动程序
*/
private static final String DRIVER = "oracle.jdbc.driver.OracleDriver"; ;/**
* ORACLE连接用URL
*/
private static final String URL = "jdbc:oracle:thin:@test2000:1521:orac"; ;/**
* 用户名
*/
private static final String USER = "user"; ;/**
* 密码
*/
private static final String PASSWord = "pswd"; ;/**
* 数据库连接
*/
private static Connection conn = null; ;/**
* SQL语句对象
*/
private static Statement stmt = null; ;/**
* @roseuid 3EDA089E02BC
*/
public LobPros()
{ ;} ;/**
* 往数据库中插入一个新的CLOB对象
*
* @param infile - 数据文件
* @throws java.lang.Exception
* @roseuid 3EDA04A902BC
*/
public static void clobInsert(String infile) throws Exception
{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); ;;;;;try {
/* 插入一个空的CLOB对象 */
stmt.executeUpdate("INSERT INTO TEST_CLOB VALUES ('111', EMPTY_CLOB())");
/* 查询此CLOB对象并锁定 */
ResultSet rs = stmt.executeQuery("SELECT CLOBCOL FROM TEST_CLOB WHERE ID='111' FOR UPDATE");
while (rs.next()) {

;;;;;/* 取出此CLOB对象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 向CLOB对象中写入数据 */
BufferedWriter out = new BufferedWriter(clob.getCharacterOutputStream());
BufferedReader in = new BufferedReader(new FileReader(infile));
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
in.close();
out.close();
}
/* 正式提交 */
conn.commit();
} catch (Exception ex) {
/* 出错回滚 */
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);
} ;/**
* 修改CLOB对象(是在原CLOB对象基础上进行覆盖式的修改)
*
* @param infile - 数据文件
* @throws java.lang.Exception
* @roseuid 3EDA04B60367
*/
public static void clobModify(String infile) throws Exception
{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); ;;;;;try {
/* 查询CLOB对象并锁定 */
ResultSet rs = stmt.executeQuery("SELECT CLOBCOL FROM TEST_CLOB WHERE ID='111' FOR UPDATE");

;while (rs.next()) {
/* 获取此CLOB对象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 进行覆盖式修改 */
BufferedWriter out = new BufferedWriter(clob.getCharacterOutputStream());
BufferedReader in = new BufferedReader(new FileReader(infile));
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
in.close();
out.close();
}
/* 正式提交 */
conn.commit();
} catch (Exception ex) {
/* 出错回滚 */
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);
} ;/**
* 替换CLOB对象(将原CLOB对象清除,换成一个全新的CLOB对象)
*
* @param infile - 数据文件
* @throws java.lang.Exception
* @roseuid 3EDA04BF01E1
*/
public static void clobReplace(String infile) throws Exception
{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); ;;;;;try {
/* 清空原CLOB对象 */

;stmt.executeUpdate("UPDATE TEST_CLOB SET CLOBCOL=EMPTY_CLOB() WHERE ID='111'");
/* 查询CLOB对象并锁定 */
ResultSet rs = stmt.executeQuery("SELECT CLOBCOL FROM TEST_CLOB WHERE ID='111' FOR UPDATE");
while (rs.next()) {
/* 获取此CLOB对象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 更新数据 */
BufferedWriter out = new BufferedWriter(clob.getCharacterOutputStream());
BufferedReader in = new BufferedReader(new FileReader(infile));
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
in.close();
out.close();
}
/* 正式提交 */
conn.commit();
} catch (Exception ex) {
/* 出错回滚 */
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);
} ;/**
* CLOB对象读取
*
* @param outfile - 输出文件名
* @throws java.lang.Exception
* @roseuid 3EDA04D80116
*/
public static void clobRead(String outfile) throws Exception

;{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); ;;;;;try {
/* 查询CLOB对象 */
ResultSet rs = stmt.executeQuery("SELECT * FROM TEST_CLOB WHERE ID='111'");
while (rs.next()) {
/* 获取CLOB对象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 以字符形式输出 */
BufferedReader in = new BufferedReader(clob.getCharacterStream());
BufferedWriter out = new BufferedWriter(new FileWriter(outfile));
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
out.close();
in.close();
}
} catch (Exception ex) {
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);
} ;/**
* 向数据库中插入一个新的BLOB对象
*
* @param infile - 数据文件
* @throws java.lang.Exception
* @roseuid 3EDA04E300F6
*/
public static void blobInsert(String infile) throws Exception
{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();

;;;;;conn.setAutoCommit(false); ;;;;;try {
/* 插入一个空的BLOB对象 */
stmt.executeUpdate("INSERT INTO TEST_BLOB VALUES ('222', EMPTY_BLOB())");
/* 查询此BLOB对象并锁定 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222' FOR UPDATE");
while (rs.next()) {
/* 取出此BLOB对象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 向BLOB对象中写入数据 */
BufferedOutputStream out = new BufferedOutputStream(blob.getBinaryOutputStream());
BufferedInputStream in = new BufferedInputStream(new FileInputStream(infile));
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
in.close();
out.close();
}
/* 正式提交 */
conn.commit();
} catch (Exception ex) {
/* 出错回滚 */
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);
} ;/**
* 修改BLOB对象(是在原BLOB对象基础上进行覆盖式的修改)
*
* @param infile - 数据文件

;;* @throws java.lang.Exception
* @roseuid 3EDA04E90106
*/
public static void blobModify(String infile) throws Exception
{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); ;;;;;try {
/* 查询BLOB对象并锁定 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222' FOR UPDATE");
while (rs.next()) {
/* 取出此BLOB对象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 向BLOB对象中写入数据 */
BufferedOutputStream out = new BufferedOutputStream(blob.getBinaryOutputStream());
BufferedInputStream in = new BufferedInputStream(new FileInputStream(infile));
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
in.close();
out.close();
}
/* 正式提交 */
conn.commit();
} catch (Exception ex) {
/* 出错回滚 */
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);

;} ;/**
* 替换BLOB对象(将原BLOB对象清除,换成一个全新的BLOB对象)
*
* @param infile - 数据文件
* @throws java.lang.Exception
* @roseuid 3EDA0505000C
*/
public static void blobReplace(String infile) throws Exception
{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); ;;;;;try {
/* 清空原BLOB对象 */
stmt.executeUpdate("UPDATE TEST_BLOB SET BLOBCOL=EMPTY_BLOB() WHERE ID='222'");
/* 查询此BLOB对象并锁定 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222' FOR UPDATE");
while (rs.next()) {
/* 取出此BLOB对象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 向BLOB对象中写入数据 */
BufferedOutputStream out = new BufferedOutputStream(blob.getBinaryOutputStream());
BufferedInputStream in = new BufferedInputStream(new FileInputStream(infile));
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
in.close();
out.close();
}
/* 正式提交 */
conn.commit();
} catch (Exception ex) {

;/* 出错回滚 */
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);
} ;/**
* BLOB对象读取
*
* @param outfile - 输出文件名
* @throws java.lang.Exception
* @roseuid 3EDA050B003B
*/
public static void blobRead(String outfile) throws Exception
{
/* 设定不自动提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); ;;;;;try {
/* 查询BLOB对象 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222'");
while (rs.next()) {
/* 取出此BLOB对象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 以二进制形式输出 */
BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(outfile));
BufferedInputStream in = new BufferedInputStream(blob.getBinaryStream());
int c;
while ((c=in.read())!=-1) {
out.write(c);
}
in.close();
out.close();
}
/* 正式提交 */

;conn.commit();
} catch (Exception ex) {
/* 出错回滚 */
conn.rollback();
throw ex;
} ;;;;;/* 恢复原提交状态 */
conn.setAutoCommit(defaultCommit);
} ;/**
* 建立测试用表格
* @throws Exception
*/
public static void createTables() throws Exception {
try {
stmt.executeUpdate("CREATE TABLE TEST_CLOB ( ID NUMBER(3), CLOBCOL CLOB)");
stmt.executeUpdate("CREATE TABLE TEST_BLOB ( ID NUMBER(3), BLOBCOL BLOB)");
} catch (Exception ex) { ;;;;;}
} ;/**
* @param args - 命令行参数
* @throws java.lang.Exception
* @roseuid 3EDA052002AC
*/
public static void main(String[] args) throws Exception
{
/* 装载驱动,建立数据库连接 */
Class.forName(DRIVER);
conn = DriverManager.getConnection(URL,USER,PASSWORD);
stmt = conn.createStatement(); ;;;;;/* 建立测试表格 */
createTables(); ;;;;;/* CLOB对象插入测试 */
clobInsert("c:/clobInsert.txt");
clobRead("c:/clobInsert.out"); ;;;;;/* CLOB对象修改测试 */
clobModify("c:/clobModify.txt");
clobRead("c:/clobModify.out"); ;;;;;/* CLOB对象替换测试 */
clobReplace("c:/clobReplace.txt");
clobRead("c:/clobReplace.out"); ;;;;;/* BLOB对象插入测试 */
blobInsert("c:/blobInsert.doc");
blobRead("c:/blobInsert.out"); ;;;;;/* BLOB对象修改测试 */

;;;;;blobModify("c:/blobModify.doc");
blobRead("c:/blobModify.out"); ;;;;;/* BLOB对象替换测试 */
blobReplace("c:/blobReplace.doc");
blobRead("c:/bolbReplace.out"); ;;;;;/* 关闭资源退出 */
conn.close();
System.exit(0);
}
}

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