展示JDBC存取ORACLE大型數(shù)據(jù)對(duì)象LOB幾種情況的示范類
2024-08-29 13:49:49
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展示JDBC存取Oracle大型數(shù)據(jù)對(duì)象LOB幾種情況的示范類import java.io.*;
import java.util.*;
import java.sql.*;public class LobPRos
{ /**
* ORACLE驅(qū)動(dòng)程序
*/
private static final String DRIVER = "oracle.jdbc.driver.OracleDriver"; /**
* ORACLE連接用URL
*/
private static final String URL = "jdbc:oracle:thin:@test2000:1521:orac"; /**
* 用戶名
*/
private static final String USER = "user"; /**
* 密碼
*/
private static final String PASSWord = "pswd"; /**
* 數(shù)據(jù)庫(kù)連接
*/
private static Connection conn = null; /**
* SQL語(yǔ)句對(duì)象
*/
private static Statement stmt = null; /**
* @roseuid 3EDA089E02BC
*/
public LobPros()
{ } /**
* 往數(shù)據(jù)庫(kù)中插入一個(gè)新的CLOB對(duì)象
*
* @param infile - 數(shù)據(jù)文件
* @throws java.lang.Exception
* @roseuid 3EDA04A902BC
*/
public static void clobInsert(String infile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 插入一個(gè)空的CLOB對(duì)象 */
stmt.executeUpdate("INSERT INTO TEST_CLOB VALUES ('111', EMPTY_CLOB())");
/* 查詢此CLOB對(duì)象并鎖定 */
ResultSet rs = stmt.executeQuery("SELECT CLOBCOL FROM TEST_CLOB WHERE ID='111' FOR UPDATE");
while (rs.next()) {
/* 取出此CLOB對(duì)象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 向CLOB對(duì)象中寫(xiě)入數(shù)據(jù) */
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) {
/* 出錯(cuò)回滾 */
conn.rollback();
throw ex;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* 修改CLOB對(duì)象（是在原CLOB對(duì)象基礎(chǔ)上進(jìn)行覆蓋式的修改）
*
* @param infile - 數(shù)據(jù)文件
* @throws java.lang.Exception
* @roseuid 3EDA04B60367
*/
public static void clobModify(String infile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 查詢CLOB對(duì)象并鎖定 */
ResultSet rs = stmt.executeQuery("SELECT CLOBCOL FROM TEST_CLOB WHERE ID='111' FOR UPDATE");
while (rs.next()) {
/* 獲取此CLOB對(duì)象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 進(jìn)行覆蓋式修改 */
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) {
/* 出錯(cuò)回滾 */
conn.rollback();
throw ex;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* 替換CLOB對(duì)象（將原CLOB對(duì)象清除，換成一個(gè)全新的CLOB對(duì)象）
*
* @param infile - 數(shù)據(jù)文件
* @throws java.lang.Exception
* @roseuid 3EDA04BF01E1
*/
public static void clobReplace(String infile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 清空原CLOB對(duì)象 */
stmt.executeUpdate("UPDATE TEST_CLOB SET CLOBCOL=EMPTY_CLOB() WHERE ID='111'");
/* 查詢CLOB對(duì)象并鎖定 */
ResultSet rs = stmt.executeQuery("SELECT CLOBCOL FROM TEST_CLOB WHERE ID='111' FOR UPDATE");
while (rs.next()) {
/* 獲取此CLOB對(duì)象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 更新數(shù)據(jù) */
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) {
/* 出錯(cuò)回滾 */
conn.rollback();
throw ex;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* CLOB對(duì)象讀取
*
* @param outfile - 輸出文件名
* @throws java.lang.Exception
* @roseuid 3EDA04D80116
*/
public static void clobRead(String outfile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 查詢CLOB對(duì)象 */
ResultSet rs = stmt.executeQuery("SELECT * FROM TEST_CLOB WHERE ID='111'");
while (rs.next()) {
/* 獲取CLOB對(duì)象 */
oracle.sql.CLOB clob = (oracle.sql.CLOB)rs.getClob("CLOBCOL");
/* 以字符形式輸出 */
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;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* 向數(shù)據(jù)庫(kù)中插入一個(gè)新的BLOB對(duì)象
*
* @param infile - 數(shù)據(jù)文件
* @throws java.lang.Exception
* @roseuid 3EDA04E300F6
*/
public static void blobInsert(String infile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 插入一個(gè)空的BLOB對(duì)象 */
stmt.executeUpdate("INSERT INTO TEST_BLOB VALUES ('222', EMPTY_BLOB())");
/* 查詢此BLOB對(duì)象并鎖定 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222' FOR UPDATE");
while (rs.next()) {
/* 取出此BLOB對(duì)象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 向BLOB對(duì)象中寫(xiě)入數(shù)據(jù) */
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) {
/* 出錯(cuò)回滾 */
conn.rollback();
throw ex;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* 修改BLOB對(duì)象（是在原BLOB對(duì)象基礎(chǔ)上進(jìn)行覆蓋式的修改）
*
* @param infile - 數(shù)據(jù)文件
* @throws java.lang.Exception
* @roseuid 3EDA04E90106
*/
public static void blobModify(String infile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 查詢BLOB對(duì)象并鎖定 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222' FOR UPDATE");
while (rs.next()) {
/* 取出此BLOB對(duì)象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 向BLOB對(duì)象中寫(xiě)入數(shù)據(jù) */
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) {
/* 出錯(cuò)回滾 */
conn.rollback();
throw ex;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* 替換BLOB對(duì)象（將原BLOB對(duì)象清除，換成一個(gè)全新的BLOB對(duì)象）
*
* @param infile - 數(shù)據(jù)文件
* @throws java.lang.Exception
* @roseuid 3EDA0505000C
*/
public static void blobReplace(String infile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 清空原BLOB對(duì)象 */
stmt.executeUpdate("UPDATE TEST_BLOB SET BLOBCOL=EMPTY_BLOB() WHERE ID='222'");
/* 查詢此BLOB對(duì)象并鎖定 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222' FOR UPDATE");
while (rs.next()) {
/* 取出此BLOB對(duì)象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 向BLOB對(duì)象中寫(xiě)入數(shù)據(jù) */
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) {
/* 出錯(cuò)回滾 */
conn.rollback();
throw ex;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* BLOB對(duì)象讀取
*
* @param outfile - 輸出文件名
* @throws java.lang.Exception
* @roseuid 3EDA050B003B
*/
public static void blobRead(String outfile) throws Exception
{
/* 設(shè)定不自動(dòng)提交 */
boolean defaultCommit = conn.getAutoCommit();
conn.setAutoCommit(false); try {
/* 查詢BLOB對(duì)象 */
ResultSet rs = stmt.executeQuery("SELECT BLOBCOL FROM TEST_BLOB WHERE ID='222'");
while (rs.next()) {
/* 取出此BLOB對(duì)象 */
oracle.sql.BLOB blob = (oracle.sql.BLOB)rs.getBlob("BLOBCOL");
/* 以二進(jìn)制形式輸出 */
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) {
/* 出錯(cuò)回滾 */
conn.rollback();
throw ex;
} /* 恢復(fù)原提交狀態(tài) */
conn.setAutoCommit(defaultCommit);
} /**
* 建立測(cè)試用表格
* @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 - 命令行參數(shù)
* @throws java.lang.Exception
* @roseuid 3EDA052002AC
*/
public static void main(String[] args) throws Exception
{
/* 裝載驅(qū)動(dòng),建立數(shù)據(jù)庫(kù)連接 */
Class.forName(DRIVER);
conn = DriverManager.getConnection(URL,USER,PASSWORD);
stmt = conn.createStatement(); /* 建立測(cè)試表格 */
createTables(); /* CLOB對(duì)象插入測(cè)試 */
clobInsert("c:/clobInsert.txt");
clobRead("c:/clobInsert.out"); /* CLOB對(duì)象修改測(cè)試 */
clobModify("c:/clobModify.txt");
clobRead("c:/clobModify.out"); /* CLOB對(duì)象替換測(cè)試 */
clobReplace("c:/clobReplace.txt");
clobRead("c:/clobReplace.out"); /* BLOB對(duì)象插入測(cè)試 */
blobInsert("c:/blobInsert.doc");
blobRead("c:/blobInsert.out"); /* BLOB對(duì)象修改測(cè)試 */
blobModify("c:/blobModify.doc");
blobRead("c:/blobModify.out"); /* BLOB對(duì)象替換測(cè)試 */
blobReplace("c:/blobReplace.doc");
blobRead("c:/bolbReplace.out"); /* 關(guān)閉資源退出 */
conn.close();
System.exit(0);
}
}
