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seems to work. However, the following returns an error:

new MathContext(precision, BigDecimal.ROUND_HALF_UP);
Error:
java: no suitable constructor found for MathContext(int,int)
    constructor java.math.MathContext.MathContext(java.lang.String) is not applicable
      (actual and formal argument lists differ in length)
    constructor java.math.MathContext.MathContext(int,java.math.RoundingMode) is not applicable
      (actual argument int cannot be converted to java.math.RoundingMode by method invocation conversion)
    constructor java.math.MathContext.MathContext(int) is not applicable
      (actual and formal argument lists differ in length)
                One is a RoundingMode and one is an int field of a BigDecimal - the error tells you that. Is there something more to your question?
– Boris the Spider
                Nov 2, 2013 at 22:49
                Why is one RoundingMode and the other int? What is the difference between the two? docs.oracle.com/javase/7/docs/api/java/math/RoundingMode.html doesn't really explain anything
– user2948708
                Nov 2, 2013 at 22:50
                Because MathContext is part of the java math API, as is RoundingMode. The ROUND_HALF_UP field of BigDecimal is part of BigDecimal's own implementation detail.
– Boris the Spider
                Nov 2, 2013 at 22:55
                Why not look at the code? Google is your friend. RoundingMode is an enum. And in fact one quick glance at the code tells you that RoundingMode.valueOf(BigDecimal.ROUND_HALF_UP) == RoundingMode.HALF_UP. And in fact the comment in the code: Returns the RoundingMode object corresponding to the legacy rounding modes (emphasis mine).
– Boris the Spider
                Nov 2, 2013 at 23:06
                Enums are classes in Java. Not ints. Google for Java enum tutorial, and read it. If a variable has the type RoundingMode, then its type is RoundingMode, and not int.
– JB Nizet
                Nov 2, 2013 at 23:12
mean absolutely the same according to Javadocs and according to source code:
public enum RoundingMode {
HALF_UP(BigDecimal.ROUND_HALF_UP),
Please use BigDecimal.ROUND_HALF_UP instead of RoundingMode.HALF_UP because of RoundingMode.HALF_UP is calling BigDecimal.ROUND_HALF_UP internally so both will give you same result but RoundingMode.HALF_UP will require one more step.
Sources from java doc:
BigDecimal.ROUND_HALF_UP
public static final RoundingMode HALF_UP
Rounding mode to round towards "nearest neighbor" unless both neighbors are equidistant, in which case round up. Behaves as for RoundingMode.UP if the discarded fraction is ≥ 0.5; otherwise, behaves as for RoundingMode.DOWN. Note that this is the rounding mode commonly taught at school. (click here to know more)
RoundingMode.HALF_UP
public final static int ROUND_HALF_UP
Behave as for ROUND_UP if the discarded fraction is >= .5; otherwise, behave as for ROUND_DOWN. (Rounds towards "nearest neighbor" unless both neighbors are equidistant, in which case rounds up.) (click here to know more)
        
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