Examples of java.util.Random.nextFloat()

java.util.Random.nextFloat()
Returns the next pseudorandom, uniformly distributed {@code float}value between {@code 0.0} and {@code 1.0} from this randomnumber generator's sequence.
The general contract of {@code nextFloat} is that one{@code float} value, chosen (approximately) uniformly from therange {@code 0.0f} (inclusive) to {@code 1.0f} (exclusive), ispseudorandomly generated and returned. All 2²⁴ possible {@code float} valuesof the form m x 2^-24, where m is a positive integer less than 2²⁴ , are produced with (approximately) equal probability.
The method {@code nextFloat} is implemented by class {@code Random}as if by:
```
  {@code}public float nextFloat()  return next(24) / ((float)(1 << 24)); }}
```
The hedge "approximately" is used in the foregoing description only because the next method is only approximately an unbiased source of independently chosen bits. If it were a perfect source of randomly chosen bits, then the algorithm shown would choose {@code float}values from the stated range with perfect uniformity.
[In early versions of Java, the result was incorrectly calculated as:
```
  {@code return next(30) / ((float)(1 << 30));}
```
This might seem to be equivalent, if not better, but in fact it introduced a slight nonuniformity because of the bias in the rounding of floating-point numbers: it was slightly more likely that the low-order bit of the significand would be 0 than that it would be 1.] @return the next pseudorandom, uniformly distributed {@code float}value between {@code 0.0} and {@code 1.0} from thisrandom number generator's sequence

        s.myBool = new Boolean(rand.nextBoolean());
        s.myByte = new Byte((byte) rand.nextInt(Byte.MAX_VALUE));
        s.myShort = new Short((short) rand.nextInt(Short.MAX_VALUE));
        s.myInteger = new Integer(rand.nextInt());
        s.myLong = new Long(rand.nextLong());
        s.myFloat = new Float(rand.nextFloat());
        s.myDouble = new Double(rand.nextDouble());
        s.myBigDecimal = new BigDecimal(rand.nextDouble());
        s.myString = Long.toHexString(rand.nextLong());
        s.myUtilDate = new java.util.Date(rand.nextLong());
        s.mySqlDate = new java.sql.Date(rand.nextLong());

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    System.out.println("Clearing the framebuffer a gazillion times...");


    Random rand = new Random(System.currentTimeMillis());
    for ( int i = 0; i < clears; i++ ) {
      glClearColor(rand.nextFloat(), rand.nextFloat(), rand.nextFloat(), 1.0f);
      glClear(GL_COLOR_BUFFER_BIT);
    }


    GLSync sync = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);

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    System.out.println("Clearing the framebuffer a gazillion times...");


    Random rand = new Random(System.currentTimeMillis());
    for ( int i = 0; i < clears; i++ ) {
      glClearColor(rand.nextFloat(), rand.nextFloat(), rand.nextFloat(), 1.0f);
      glClear(GL_COLOR_BUFFER_BIT);
    }


    GLSync sync = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);

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    System.out.println("Clearing the framebuffer a gazillion times...");


    Random rand = new Random(System.currentTimeMillis());
    for ( int i = 0; i < clears; i++ ) {
      glClearColor(rand.nextFloat(), rand.nextFloat(), rand.nextFloat(), 1.0f);
      glClear(GL_COLOR_BUFFER_BIT);
    }


    GLSync sync = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);

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      float[] orig = new float[1024];
      MutableSparseFloatArray fromEmpty = new MutableSparseFloatArray(new float[1024]);
      float density = 0.2f;
      int idx = 0;
      while (rand.nextFloat() > density) {
        idx++;
      }
      int count = 0;
      while (idx < orig.length) {
        float val = rand.nextFloat();

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      while (rand.nextFloat() > density) {
        idx++;
      }
      int count = 0;
      while (idx < orig.length) {
        float val = rand.nextFloat();
        orig[idx] = val;
        fromEmpty.set(idx, val);
        count++;
        idx += 1;
        while (rand.nextDouble() > density) {

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      MutableSparseFloatArray fromPartial = new MutableSparseFloatArray(copy);
      
      // do 128 modifications
      int mods = 128;
      for (int i = 0; i < mods; i++) {
        float val = rand.nextFloat();
        idx = rand.nextInt(orig.length);
        orig[idx] = val;
        fromEmpty.set(idx, val);
        fromPartial.set(idx, val);        
      }

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      for (int i = 0; i < 32*1024; i++) {
        int idx = r.nextInt(orig.length);
        if (r.nextBoolean()) {
          assertTrue("orig "+orig[idx]+" not the same as arr "+arr.get(idx)+" at idx="+idx, orig[idx] == arr.get(idx));
        } else {
          float val = r.nextFloat();
          orig[idx] = val;
          arr.set(idx, val);
        }
      }

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      arr = new MutableSparseFloatArray(new float[orig.length]);
      int[] idxs = new int[1024*1024];
      float[] vals = new float[idxs.length];
      for (int i = 0; i < idxs.length; i++) {
        idxs[i] = r.nextInt(orig.length);
        vals[i] = r.nextFloat();
      }
      
      long markTime = System.currentTimeMillis();
      for (int i = 0; i < idxs.length; i++) {
        orig[i] = vals[i];

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    try {
      float[] orig = new float[32*1024*1024];
      float density = 0.4f;
      Random rand = new Random(SEED);
      int idx = 0;
      while (rand.nextFloat() > density) {
        idx++;
      }
      int count = 0;
      while (idx < orig.length) {
        orig[idx] = rand.nextFloat();

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