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How to Generate Unique Random Numbers?
[code:1xmtc0iv] import com.sun.crypto.provider.RSACipher; import java.util.Random; public class RandomRange { static int START = 1; static int END; static Random random = new Random(); private static void showRandomInteger(int aStart, int aEnd, Random aRandom){ if ( aStart > aEnd ) { throw new IllegalArgumentException("Start cannot exceed End."); } //get the range, casting to long to avoid overflow problems long range = (long)aEnd - (long)aStart + 1; // compute a fraction of the range, 0 <= frac < range long fraction = (long)(range * aRandom.nextDouble()); int randomNumber = (int)(fraction + aStart); // System.out.println("Hi this is from senthil == >"+ j ); log("Generated : " + randomNumber); } private static void log(String aMessage){ System.out.println(aMessage); } public static void main(String aArgs[]){ int countrec = 9; log("Generating random integers in the range "+START+"...." + countrec); END = countrec - 1; for (int idx = START; idx <= 5; ++idx){ showRandomInteger(START, END, random); } log("Done."); } } [/code:1xmtc0iv]