| 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);
}
二、 BLOB对象的存取
1、 向数据库中插入一个新的BLOB对象
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);
}
2、修改BLOB对象（是在原BLOB对象基础上进行覆盖式的修改）
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);
}
3、替换BLOB对象（将原BLOB对象清除，换成一个全新的BLOB对象）
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);
}
4、BLOB对象读取
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 */
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