Weblogic 下 oracle 的 blob 操作
最后公司的WEB服务器要用 WebLogic 8.1 替换原来的 Resin ，因为要用webloic 的 数据库连接池，原有的程序需要变动
（1）向 blob 字段写入值
String medpk = dao.getElementPK(cn, vo);
evo.setEle_elementId(medpk);
evo.setEle_contentid(conpk);
evo.setEle_type("23");
dao.addElementRelation(cn, evo);
evo.setMmsnews_elementID(medpk);
//Connection conn=JdbcConnectionPool.getConnection();
try {
String sql =
"insert into OM_CM_MMSNEWS (elementid,title,content) values(?,?,empty_blob())"; //1.blob字段插入空值
PreparedStatement ps = cn.prepareStatement(sql);
ps.setString(1, evo.getEle_elementId());
ps.setString(2, evo.getMmsnews_title());
ps.execute();
sql =
"select content from OM_CM_MMSNEWS where elementid=" + medpk + " for update"; //2.更新指定记录的 blob字段
Statement st = cn.createStatement();
ResultSet rs = st.executeQuery(sql);
File file = new File(evo.getMmsnews_content());
if (rs.next()) {
OracleThinBlob blob = (weblogic.jdbc.vendor.oracle.OracleThinBlob) rs.getBlob(1);
//必须用weblogic 的jar包
OutputStream outStream = blob. getBinaryOutputStream();
InputStream fin = new FileInputStream(file);
byte[] b = new byte[blob.getBufferSize()];
int len = 0;
while ((len = fin.read(b)) != -1) {
outStream.write(b, 0, len);
}
fin.close();
outStream.flush();
outStream.close();
}
rs.close();
st.close();
logger.error("this MmsNews is save!");
} catch (Exception ex) {
logger.error(ex.getMessage());
throw new Exception(ex.getMessage());
}
（2）提取blob字段的值，并保存为文件
private static void getZipFile(String contentid, String filepath,
String zipfile) throws
DOException {
String sql = "select content from om_cm_mmsnews a where a.elementid in (select b.elementid from om_cm_elementrelation b where b.contentid in (select c.contentid from om_cm_content c where c.contentid=?))";
Connection conn = null;
try {
//建立文件夹
File tempDicFile = new java.io.File(filepath);
tempDicFile.mkdirs();
//提取 blob 字段的内容并保存为 zip 文件
conn = JdbcConnectionPool.getConnection();
PreparedStatement ps = conn.prepareStatement(sql);
ps.setString(1, contentid); //传入 contentid
ResultSet rst = ps.executeQuery();
while (rst.next()) {
/* 取出此BLOB对象 */
java.sql.Blob blob = rst.getBlob("content");
if (blob != null) {
/* 以二进制形式输出 */
BufferedInputStream in = new BufferedInputStream(blob.
getBinaryStream());
BufferedOutputStream out = new BufferedOutputStream(new
FileOutputStream(zipfile));
byte[] buf = new byte[1024];
while (true)
{
int count = in.read(buf);
if (count <= 0)
{
break;
}
out.write(buf, 0, count);
}
in.close();
out.close();
}
}
rst.close();
ps.close();
conn.close();
logger.error("Mmspreview -->getZipFile 创建zip文件成功");
} catch (Exception ex) {
logger.error("Mmspreview -->getZipFile 创建zip文件失败!!!!!" +
ex.getMessage());
} finally {
PublicUtilit.rapidReleaseConnection(null, conn, null, null);
}
}