创建一个表LOB_TEST
 
CREATE TABLE LOB_TEST
(
  A  NUMBER(10),
  B  BLOB,
  C  CLOB
)

下面是java代码
package test;

import java.io.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Random;

/**
 * A general-purpose SQL interpreter program.
 **/
public class ExecuteSQL {
 final static String url="jdbc:oracle:thin:@127.0.0.1:1521:test"; //orcl为数据库的SID
 final static String user="test";
 final static String password="test";
 final static String driver="oracle.jdbc.driver.OracleDriver";
 final static String filePath="D:\\test\\test.txt";
 
    public static void main(String[  ] args) {
        Connection conn = null;  // Our JDBC connection to the database server
        PreparedStatement pstmt = null;
        Random random=new Random();
        String num=String.valueOf(random.nextLong());
        try {
         StringBuffer sql=new StringBuffer();
         StringBuffer updateSql=new StringBuffer();
         sql.append("INSERT INTO guof_test (A,C)  values ('"+num+"',EMPTY_CLOB())");
         updateSql.append("SELECT A,C from guof_test WHERE A= ? For update");
            conn = getConnection();
            conn.setAutoCommit(false);
            Statement state = conn.createStatement( );
            state.executeUpdate(sql.toString());
            state.close();
            pstmt = conn.prepareStatement(updateSql.toString());
            pstmt.setString(1, num);
            ResultSet rest = pstmt.executeQuery();
            File parsed = new File(filePath);
            BufferedReader in =new BufferedReader(new InputStreamReader(new FileInputStream(parsed)));
            String readStr=null;
        
            if(rest.next()){
              oracle.sql.CLOB clob = (oracle.sql.CLOB) rest.getClob("C");
                 Writer outStream = clob.getCharacterOutputStream();
                try{
                while((readStr=in.readLine())!=null){
                     outStream.write(readStr);
                     }
                    outStream.close();
                    }catch (IOException e)
                {
                    e.printStackTrace();
                }
                finally
                {
                    try
                    {
                       outStream.close();
                    } catch (IOException e)
                    {
                        e.printStackTrace();
                    }         
                } 
           
            }
            conn.commit();
            conn.setAutoCommit(true);
        }
        catch (Exception e) {
            e.printStackTrace();;
          
        }

          finally {
            try { conn.close( ); } catch (Exception e) {  }
        }
    }

 /**
  * @return
  * @throws ClassNotFoundException
  * @throws SQLException
  */
 public static Connection getConnection() throws ClassNotFoundException, SQLException {
  Connection conn;
  
  if (url == null)
      throw new IllegalArgumentException("No database specified");

   if (driver != null) Class.forName(driver);

  conn = DriverManager.getConnection(url, user, password);
 return conn;
 }
}