public static void md5toFile() {
        char[] c = {'0','1','2','3','4','5','6','7','8','9',
                'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};


        try {
           /* Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
            Connection conn = null;
            Statement statement = null;
            conn = DriverManager.getConnection("jdbc:oracle:thin:@10.0.0.33:1521:orcl", "dcc", "dcc");
            PreparedStatement oraPs = null;
            String oraInsertSql = "insert into t_md5dict(original,md5char) values (?,?)";
            oraPs = conn.prepareStatement("delete from t_md5dict");
            oraPs.executeUpdate();
            long curtime = System.currentTimeMillis();
            System.out.println(curtime);
            //下面不能放入For循环中.
            oraPs = conn.prepareStatement(oraInsertSql);*/

                RandomAccessFile randomFile = new RandomAccessFile("E:\\test\\md5\\all_md5.txt", "rw");
            for (int c1=0;c1<=c.length-1;c1++) {

                for (int c2=0;c2<=c.length-1;c2++) {
                    long curtime = System.currentTimeMillis();
                    for (int c3=0;c3<=c.length-1;c3++) {
                        for (int c4=0;c4<=c.length-1;c4++)
                        {  // 文件长度，字节数
                            long fileLength = randomFile.length();
                            //将写文件指针移到文件尾。
                            randomFile.seek(fileLength);
                            String s = ""+c[c1]+c[c2]+c[c3]+c[c4];
                            randomFile.writeBytes(s+"\t\t"+MD5.GetMD5Code(s).toUpperCase()+"\r\n");
                        }
                        System.out.println(""+c[c1]+","+c[c2]+","+c[c3]);
                        //oraPs.executeBatch();
                    }
                }
            }
                randomFile.close();
            //oraPs.executeBatch();
            //oraPs.executeUpdate();
            //conn.commit();

            //conn.close();
            //System.out.println(System.currentTimeMillis() - curtime);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }