Shulou(Shulou.com)05/31 Report--

Today, I will talk to you about how to deal with blob data in mysql. Many people may not know much about it. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

The specific code is as follows:

Package epoint.mppdb_01.h4c;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 connection 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 connection 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 = "h4c"; 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 {/ / close connection if (conn! = null) {try {conn.close (); conn = null } catch (Exception e) {e.printStackTrace ();} public static void main (String [] args) throws Exception {getMySQLblobToHDFS ();} / / HDFS attachment upload 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 ("upload succeeded!") ;} / / download 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 ("download successful!") After reading the above, do you have any further understanding of how to deal with blob data in mysql? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.