展示JDBC存取ORACLE大型数据对象LOB几种情况的示范类
[*]package test;
[*]
[*]import java.io.*;
[*]import java.util.*;
[*]import java.sql.*;
[*]
[*]/**
[*] * 展示JDBC存取ORACLE大型数据对象LOB几种情况的示范类
[*] *
[*] *
[*] * @version 1.0
[*] *
[*] */
[*]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:@10.11.25.66:1521:wjc";
[*]
[*] /**
[*] * 用户名
[*] */
[*] private static final String USER = "wjc";
[*]
[*] /**
[*] * 密码
[*] */
[*] private static final String PASSWORD = "anyue";
[*]
[*] /**
[*] * 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"); </
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