Java Tool class for random string fetching

Source: Java Random String Tool class

Source code: Http://www.zuidaima.com/share/1550463479532544.htm

Java random string of the tool class can be all numbers, characters, can also be a combination of characters and numbers of the tool class, hope to bring you help

Package Com.zuidaima.test;import Java.util.random;public class Randomutils {public static final String Allchar = "0123456 789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ ";p ublic static final String Letterchar =" ABCDEFGHIJKLLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZ ";p ublic static final String Numberchar =" 0123456789 ";      /** * Returns a fixed-length random string (containing only uppercase and lowercase letters, numbers) * @param length random string lengths * @author www.zuidaima.com * @return Random string */public static String generatestring (int length) {stringbuffer sb = new StringBuffer (); Random random = new random (), for (int i = 0; i < length; i++) {Sb.append (Allchar.charat (Random.nextint (Allchar.length () )));} return sb.tostring ();}      /** * Returns a fixed-length random, pure-letter string (containing only uppercase and lowercase letters) * @param length random string lengths * @author www.zuidaima.com * @return Random string             */public static String generatemixstring (int length) {stringbuffer sb = new StringBuffer ();             Random random = new random (); for (int i = 0; i < Length             i++) {sb.append (Allchar.charat (Random.nextint (Letterchar.length ())));     } return sb.tostring (); }/** * Returns a fixed-length random pure capital letter string (with uppercase and lowercase letters only) * * @param length random string lengths * @return Random String */public s     Tatic String generatelowerstring (int length) {return generatemixstring (length). toLowerCase (); }/** * Returns a fixed-length random plain lowercase letter string (with only uppercase letters) * * @param length random string lengths * @author www.zuidaima.com * @re Turn random String */public static string generateupperstring (int length) {return generatemixstring (length)     . toUpperCase (); }/** * Generates a fixed length of pure 0 strings * * @param length string lengths * @return Pure 0 Strings */public static string gene             ratezerostring (int length) {stringbuffer sb = new StringBuffer ();             for (int i = 0; i < length; i++) {sb.append (' 0 ');     } return sb.tostring (); }     /** * Generates a fixed-length string based on a number that is not long enough to be preceded by 0 * * @param num number * @param fixdlenth string length * @auth             or www.zuidaima.com * @return fixed-length string */public static string tofixdlengthstring (long num, int fixdlenth) {             StringBuffer sb = new StringBuffer ();             String strnum = string.valueof (num);              if (fixdlenth-strnum.length () >= 0) {sb.append (generatezerostring (Fixdlenth-strnum.length ())); } else {throw new RuntimeException ("Convert number + num +" to a string with a length of "+ Fixdlenth +") An exception occurred!             ");             } sb.append (Strnum);     return sb.tostring (); }/** * Generates a fixed-length string based on number, length is not enough for the previous 0 * * @param num number * @param fixdlenth string length * @aut             Hor www.zuidaima.com * @return Fixed-length string */public static string tofixdlengthstring (int num, int fixdlenth) {             StringBuffer sb = new StringBuffer (); String Strnum = StRing.valueof (num);              if (fixdlenth-strnum.length () >= 0) {sb.append (generatezerostring (Fixdlenth-strnum.length ())); } else {throw new RuntimeException ("Convert number + num +" to a string with a length of "+ Fixdlenth +") An exception occurred!             ");             } sb.append (Strnum);     return sb.tostring (); /** * generates different len digits each time * @param param * @return Fixed-length number */public static int Getnotsimple (int[         ] Param,int len) {Random rand = new Random ();             for (int i = param.length; i > 1; i--) {int index = rand.nextint (i);             int tmp = Param[index];             Param[index] = param[i-1];         PARAM[I-1] = tmp;         } int result = 0;         for (int i = 0; i < len; i++) {result = result * + Param[i];    } return result; } public static void Main (string[] args) {System.out.println (GeneratestriNg (10));             System.out.println (generatemixstring (10));             System.out.println (generatelowerstring (10));             System.out.println (generateupperstring (10));             System.out.println (generatezerostring (10));             System.out.println (tofixdlengthstring (123, 10));             System.out.println (Tofixdlengthstring (123L, 10));            Int[] in = {1,2,3,4,5,6,7};    System.out.println (Getnotsimple (in,3)); } }

Java Tool class for random string fetching