oracle-操作lob文件（举例Blob）

一.写入BLOB



1.先在blob中插入empty_blob()



2.获得对刚刚插入记录的引用

BLOB blob = (BLOB) rs.getBlob("你的blob字段名称");

3.写入

OutputStream out = blob.getBinaryOutputStream();

out.write(ENCYPWD);//注意这里

二.读出BLOB



1.blob = rs.getBlob("你的blob字段名称");

、

2.InputStream is = blob.getBinaryStream();

int length = (int) blob.length();

byte[] buffer = new byte[length];

is.read(buffer);

is.close();



3.你有了is就随便处理了

比如说输出到一个文件

FileOutputStream fo = new FileOutputStream(filename);//数据到的文件名

fo.write(buffer);

fo.close();

一、BLOB操作1、入库（1）JDBC方式     //通过JDBC获得数据库连接    Class.forName("oracle.jdbc.driver.OracleDriver");    Connection con = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:testdb", "test", "test");    con.setAutoCommit(false);    Statement st = con.createStatement();    //插入一个空对象empty_blob()    st.executeUpdate("insert into TESTBLOB (ID, NAME, BLOBATTR) values (1, "thename", empty_blob())");    //锁定数据行进行更新，注意“for update”语句    ResultSet rs = st.executeQuery("select BLOBATTR from TESTBLOB where ID=1 for update");    if (rs.next())    {        //得到java.sql.Blob对象后强制转换为oracle.sql.BLOB        oracle.sql.BLOB blob = (oracle.sql.BLOB) rs.getBlob("BLOBATTR");        OutputStream outStream = blob.getBinaryOutputStream();        //data是传入的byte数组，定义：byte[] data        outStream.write(data, 0, data.length);    }    outStream.flush();    outStream.close();    con.commit();    con.close();  2、出库    //获得数据库连接    Connection con = ConnectionFactory.getConnection();    con.setAutoCommit(false);    Statement st = con.createStatement();    //不需要“for update”    ResultSet rs = st.executeQuery("select BLOBATTR from TESTBLOB where ID=1");    if (rs.next())    {        java.sql.Blob blob = rs.getBlob("BLOBATTR");        InputStream inStream = blob.getBinaryStream();        //data是读出并需要返回的数据，类型是byte[]        data = new byte[input.available()];        inStream.read(data);        inStream.close();    }    inStream.close();    con.commit();    con.close();