mysql中blob数据处理方式

具体代码如下所示：

package epoint.mppdb_01.h3c;
import java.io.file;
import java.io.fileinputstream;
import java.io.fileoutputstream;
import java.io.inputstream;
import java.io.outputstream;
import java.net.uri;
import java.sql.blob;
import java.sql.connection;
import java.sql.drivermanager;
import java.sql.resultset;
import java.sql.statement;
import org.apache.commons.net.ftp.ftpclient;
import org.apache.commons.net.ftp.ftpreply;
import org.apache.hadoop.conf.configuration;
import org.apache.hadoop.fs.fsdatainputstream;
import org.apache.hadoop.fs.filesystem;
import org.apache.hadoop.fs.path;
import org.apache.hadoop.io.ioutils;
public class mysqlblobtomppphoto {
  // mysql连接
  public static connection getmysqlconnection() throws exception {
    string mysqldriver = "com.mysql.jdbc.driver";
    string mysqlurl = "jdbc:mysql://192.168.186.13:3306/bigdata_scene03_rktj";
    string mysqlusername = "root";
    string mysqlpassword = "gepoint";
    connection mysqlconn = drivermanager.getconnection(mysqlurl, mysqlusername, mysqlpassword);
    return mysqlconn;
  }
  // mpp连接
  public static connection getmppconnection() throws exception {
    string mppdriver = "com.mpp.jdbc.driver";
    string mppurl = "jdbc:mpp://192.168.186.14:5258/bigdata_scene03_rktj";
    string mppusername = "mpp";
    string mpppassword = "h3c";
    connection mppconn = drivermanager.getconnection(mppurl, mppusername, mpppassword);
    return mppconn;
  }
  //
  public static void getmysqlblobtohdfs() throws exception {
    connection conn = getmysqlconnection();
    resultset rs = null;
    try {
      string sql = "select row_id,photo from t_rk_baseinfo_blob limit 10";
      statement prest = conn.preparestatement(sql);
      rs = prest.executequery(sql);
      while (rs.next()) {
        int row_id = rs.getint(1);
        blob photo = rs.getblob(2);
        system.out.println(row_id + " " + photo);
        inputstream in = photo.getbinarystream();
        outputstream out = new fileoutputstream("h:/photo/" + row_id + ".jpg");
        int len = 0;
        byte[] buffer = new byte[1024];
        while ((len = in.read(buffer)) != -1) {
          out.write(buffer, 0, len);
        }
        upload("h:/photo/" + row_id + ".jpg");
      }
      prest.close();
      rs.close();
    } catch (exception e) {
      e.printstacktrace();
    } finally {
      // 关闭连接
      if (conn != null) {
        try {
          conn.close();
          conn = null;
        } catch (exception e) {
          e.printstacktrace();
        }
      }
    }
  }
  public static void main(string[] args) throws exception {
    getmysqlblobtohdfs();
  }
  // hdfs附件上传
  public static void upload(string uploadpath) throws exception {
    configuration conf = new configuration();
    uri uri = new uri("hdfs://192.168.186.14:8020");
    filesystem fs = filesystem.get(uri, conf, "hdfs");
    path resp = new path(uploadpath);
    path destp = new path("/photo");
    if (!fs.exists(destp)) {
      fs.mkdirs(destp);
    }
    fs.copyfromlocalfile(resp, destp);
    fs.close();
    system.out.println("***********************");
    system.out.println("上传成功！");
  }
  // hdfs附件下载
  public static void download() throws exception {
    configuration conf = new configuration();
    string dest = "hdfs://192.168.186.14:/photo/11.png";
    string local = "d://11.png";
    filesystem fs = filesystem.get(uri.create(dest), conf, "hdfs");
    fsdatainputstream fsdi = fs.open(new path(dest));
    outputstream output = new fileoutputstream(local);
    ioutils.copybytes(fsdi, output, 4096, true);
    system.out.println("***********************");
    system.out.println("下载成功！");
  }
}

总结

以上所述是小编给大家介绍的mysql中blob数据处理方式，希望对大家有所帮助