帮忙看一下？为什么错，太奇怪了。例子读取oracle的clob

Question

用JDBC存储ORACLE的BLOB字段模板import java.io.*;import java.sql.*;
import oracle.jdbc.driver.*;
import oracle.sql.*;public class testSuite
{    public void writeBLOB() throws Exception
    {
        Class.forName("oracle.jdbc.driver.OracleDriver");
        Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@myhost:1521:mysid","myname","mypassword");
        conn.setAutoCommit(false);        String filename = "d:/passion.jpg";
        Statement st = conn.createStatement();
        int b= st.executeUpdate("insert into blobsamp values(60,empty_blob())"); //注意在插入  //BLOB字段时必须先插入一个空字段
        st.execute("commit");
        System.out.println("Int Value:\t"+b);        ResultSet rs= st.executeQuery("select * from blobsamp for update");
        rs.next();
        BLOB blob=((oracle.jdbc.driver.OracleResultSet)rs).getBLOB(2);
        rs.close();
        FileInputStream instream = new FileInputStream(filename);
        OutputStream outstream = blob.getBinaryOutputStream();        int chunk = blob.getChunkSize();
        System.out.println(chunk);
        byte[] buff = new byte[chunk];
        int le;        System.out.println("Writing file " + filename+ " into blob.....");
        while( (le=instream.read(buff)) !=-1)
        {
            outstream.write(buff,0,le);
        }
        outstream.close();
        st.execute("commit");
        System.out.println("Blob Written.....");
        instream.close();
        conn.commit();
        st.close();
        conn.close();
        conn = null;
        System.out.println("Database updated.....");
    }    public void readBLOB() throws Exception
    {
        //Reading the BLOB :
        String sql = "select id,blob_col from blobsamp where id=?";
        Class.forName("oracle.jdbc.driver.OracleDriver");
        ResultSet rs;
        BLOB blob=null;
        Connection con = DriverManager.getConnection("jdbc:oracle:thin:@myhost:1521:mysid","myname","mypassword");
        PreparedStatement pstmt = con.prepareStatement(sql);
        pstmt.setInt(1,70);
        rs = pstmt.executeQuery();
        while(rs.next())
        {
            blob = ((OracleResultSet)rs).getBLOB("blob_col");
        }
        rs.close();
        InputStream blobStream = blob.getBinaryStream();
        System.out.println("blob length : " + blob.length());
        FileOutputStream fileOutStream = new FileOutputStream("d:\\abc.jpg");
        byte[] buffer = new byte[10];
        int nbytes = 0;
        while ((nbytes = blobStream.read(buffer))!= -1)
        fileOutStream.write(buffer,0,nbytes);
        fileOutStream.flush();
        fileOutStream.close();
        blobStream.close();
        pstmt.close();
        con.commit();
        con.close();
    }}