Mysql automatic backup, using MD5 for unique backup _ MySQL

1. name the backup database tempsql and calculate its MD520540. (for MD5 calculation method, see MD5java) spanstylewhite-space: Slave-uroot-pwugroupweixinD: mysql_backtemp 1. name the backup database temp. SQL, calculate its MD5 value (for MD5 calculation method, see MD5.java)

String dos = "cmd/c mysqldump-uroot-pwugroup weixin> D:/mysql_back/temp. SQL "; // doscommand runtime.getruntime(cmd.exe c (dos); // execute the doscommand Thread. sleep (1000); // sleep for one minute to prevent the following code from executing too fast File fileTemp = new File ("D:/mysql_back/temp. SQL "); String fileTempString = FileString. getFileString (fileTemp); String fileTempMd5 = MD5.GetMD5Code (fileTempString );

2. traverse the backup directory and calculate the MD5 value of the files under the Directory, respectively compared with temp. SQL

File dir = new File ("D:/mysql_back"); File [] fs = dir. listFiles (); for (int I = 1; I <fs. length; I ++) {// I starts from 1 to skip temp. SQL file String fileString = FileString. getFileString (fs [I]); String fileMd5 = MD5.GetMD5Code (fileString); // System. out. println (fileTempMd5); // System. out. println (fileMd5); if (fileMd5.equals (fileTempMd5) {// exit the System if the file is the same as the file. exit (0 );}}

4. exit the program if there is the same

If (fileMd5.equals (fileTempMd5) {// exit System. exit (0) if there is a file with the same name as this file );}

5. if all files in the directory are different, rename temp to the current time to save

String name = new SimpleDateFormat ("yyyyMMddHHmmss "). format (new Date ()). toString (); // get the current time and format File rename = new File (fileTemp. getParent () + File. separator + "weixin _" + name + ". SQL "); // If this file does not exist, rename the created temp file // System. out. println (rename); fileTemp. renameTo (rename); System. exit (0 );

Code:

Package backup; import java. io. file; import java. io. IOException; import java. text. simpleDateFormat; import java. util. date; /***** @ author wuxingye **/public class Main {/***** main function ** @ param args * @ throws IOException * @ throws InterruptedException */public static void main (String [] args) throws IOException, InterruptedException {String dos = "cmd/c mysqldump-uroot-pwugroup weixin> D:/mysql_back/temp. SQL "; // doscommand runtime.getruntime(cmd.exe c (dos); // execute the doscommand Thread. sleep (1000); // sleep for one minute to prevent the following code from executing too fast File fileTemp = new File ("D:/mysql_back/temp. SQL "); String fileTempString = FileString. getFileString (fileTemp); String fileTempMd5 = MD5.GetMD5Code (fileTempString); // TODO Auto-generated method stubFile dir = new File ("D:/mysql_back "); file [] fs = dir. listFiles (); for (int I = 1; I <fs. length; I ++) {// I starts from 1 to skip temp. SQL file String fileString = FileString. getFileString (fs [I]); String fileMd5 = MD5.GetMD5Code (fileString); // System. out. println (fileTempMd5); // System. out. println (fileMd5); if (fileMd5.equals (fileTempMd5) {// exit the System if the file is the same as the file. exit (0) ;}} String name = new SimpleDateFormat ("yyyyMMddHHmmss "). format (new Date ()). toString (); // get the current time and format File rename = new File (fileTemp. getParent () + File. separator // If this file is not available, rename the created temp file + "weixin _" + name + ". SQL "); // System. out. println (rename); fileTemp. renameTo (rename); System. exit (0 );}}

FileString. java

Package backup; import java. io. bufferedReader; import java. io. file; import java. io. fileReader; import java. io. IOException;/*** convert File to String, convert the file into a string ** @ author wuxingye */public class FileString {/***** @ param file * @ return returns the file content, returns */public static String getFileString (File file) {BufferedReader br = null; StringBuffer sb = null; try {br = new BufferedReader (new FileReader (File )); sb = new St RingBuffer (); String str = null; // read a row at a time until null is read as the end of the file while (str = br. readLine ())! = Null) {if (! Str. contains ("Dump completed on") {// The last row of the exported data file is -- Dump completed on 20:03:21 // the end time of the last row of the exported database, in this way, the MD5 of files everywhere is different, so this line of sb is removed. append (str); // StringBuffer is faster than String} br. close ();} catch (IOException e) {e. printStackTrace ();} finally {if (br! = Null) {try {br. close () ;}catch (IOException e1) {}} return sb. toString ();}}

MD5.java

Package backup; import java. security. messageDigest; import java. security. noSuchAlgorithmException; /***** obtain the MD5 value of the String ** @ author from the network **/public class MD5 {// Global Array private final static String [] strDigits = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "", "B", "c", "d", "e", "f"}; public MD5 () {} // return format: numeric and String/***** @ param bByte * @ return byte to convert to String, hexadecimal String */private static String byteToArrayString (byte bByte) {int iRet = bByte; // System. out. println ("iRet =" + iRet); if (iRet <0) {iRet + = 256;} int iD1 = iRet/16; int iD2 = iRet % 16; return strDigits [iD1] + strDigits [iD2];} // The return format is only numbers. // private static String byteToNum (byte bByte) {// int iRet = bByte; // System. out. println ("iRet1 =" + iRet); // if (iRet <0) {// iRet + = 256; //} // return String. valueOf (iRet); // Convert the byte array to a hexadecimal string/*** call byteToArrayString ** @ param bByte * @ return to convert the byte to a string, hexadecimal String */private static String byteToString (byte [] bByte) {StringBuffer sBuffer = new StringBuffer (); for (int I = 0; I <bByte. length; I ++) {sBuffer. append (byteToArrayString (bByte [I]);} return sBuffer. toString ();}/***** @ param strObj * @ return obtain the MD5 value of the String */public static String GetMD5Code (String strObj) {// System. out. println (strObj); String resultString = null; try {resultString = new String (strObj); MessageDigest md = MessageDigest. getInstance ("MD5"); // md. digest () The return value of this function is the byte array resultString = byteToString (md. digest (strObj. getBytes ();} catch (NoSuchAlgorithmException ex) {ex. printStackTrace () ;}return resultString ;}}