Rounding mode to round towards negative infinity. If the result is positive, behave as for RoundingMode.`DOWN`

; if negative, behave as for `RoundingMode`

.UP. Note that this rounding mode never increases the calculated value.

It is just matter of whole number and its position against number chart. From here you can see `javadocs`

.

```
public static int round(float a)
```

Returns the closest int to the argument, with ties rounding up.

```
Special cases:
```

- If the argument is
`NaN`

, the result is 0. - If the argument is negative infinity or any value less than or equal to the value of
`Integer.MIN_VALUE`

, the result is equal to the value of`Integer.MIN_VALUE`

. -
If the argument is positive infinity or any value greater than or equal to the value of

`Integer.MAX_VALUE`

, the result is equal to the value of`Integer.MAX_VALUE`

.Parameters:

a – a floating-point value to be rounded to an integer.

```
Returns:
```

the value of the argument rounded to the nearest int value.

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solved Why does Java and Javascript Math.round(-1.5) to -1?