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1、往数据库中插入一个新的CLOB对象 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); } 2、修改CLOB对象（是在原CLOB对象基础上进行覆盖式的修改） 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); } 3、替换CLOB对象（将原CLOB对象清除，换成一个全新的CLOB对象） 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); } 4、CLOB对象读取 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); } 转载于:https://my.oschina.net/yululaile/blog/56004
