Java Generate Random Number Between Two Given Values

Java Generate Random Number Between Two Given Values

You could use e.g. r.nextInt(101)

For a more generic "in between two numbers" use:

Random r = new Random();
int low = 10;
int high = 100;
int result = r.nextInt(high-low) + low;

This gives you a random number in between 10 (inclusive) and 100 (exclusive)

random integers between 2 values

If you want a value between two integer values (min and max)
Here you go:

Random r = new Random();
int randInt = r.nextInt(max-min) + min;
System.out.println(randInt);

So max would be 5 and min would be 2 if you want a integer between 2 and 5

Need to generate random numbers between two values ignoring the given values

The correct formula for random numbers in a range is Min + (Math.random() * (Max - Min)) (including lower bound and excluding upper bound).

For your numbers the correct way would be

double fv = (-7) + Math.random() * (0 - -7);

Since you used only one - in the formula the Minvalue was assumed to be 7 and not -7 which leads to wrong results.

How to generate a random number between two values then set to TextView?

Random random = new Random();
int value = random.nextInt(max - min) + min;
num1.setText(value+"");

You can't use .setText(value), because integer will be a resource link to /res/strings! Add +"" after number!!!

There are two (or more) methods:

public final void setText (CharSequence text) - To set text

public final void setText (int resid) - to set text from file /res/string/strings.xml

Getting random numbers in Java between two numbers

The static method Math.random() returns a number between 0 and 1 so you just have to multiply the result with the difference between you minimal and maximal value and add this to your minimal value.

int min = 65;
int max = 122;
int random = (int) min + (max - min) * Math.random();

Generating a Random Number between 1 and 10 Java

As the documentation says, this method call returns "a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive)". This means that you will get numbers from 0 to 9 in your case. So you've done everything correctly by adding one to that number.

Generally speaking, if you need to generate numbers from min to max (including both), you write

random.nextInt(max - min + 1) + min

getting a random long in range of two values

The delay value will be a random number from 2500 to 4999, since nextInt upper bound is exclusive. From the Java SE Specification:

public int nextInt(int bound)

Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence. The general contract of nextInt is that one int value in the specified range is pseudorandomly generated and returned. All bound possible int values are produced with (approximately) equal probability.

rand.nextInt(5000-2500) + 2500 is the same as rand.nextInt(2500) + 2500 (which in my opinion is a cleaner way to write it).

Also int values are converted to long without losing information (long has a wider range than int so no problems there). From the Java SE Specification:

A conversion from type int to type long requires run-time sign-extension of a 32-bit integer value to the 64-bit long representation. No information is lost.

Finally about random not being truly random, you are right it's pseudo-random (which means that all posible numbers has not an exact equal probability, but an approximately equal one). I'm not completely sure what are you using this code for, but I think this will be "random enough" for your needs.

You can have a look at this post about random values in java between a given range.
And this post about Random randomness.

PD: A nice improvement in your code (imho) would be making the rand variable private static instead of local.

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