src/java.base/share/classes/java/math/BigDecimal.java

*** 1991,2000 ****
--- 1991,2034 ----
          result[0] = lhs.divideToIntegralValue(divisor, mc);
          result[1] = lhs.subtract(result[0].multiply(divisor));
          return result;
      }
  
+ 
+     /**
+      * Returns an approximation to the square root of {@code this}
+      * with rounding according to the context settings.
+      *
+      * <p>The preferred scale of the returned result is equal to
+      * {@code floor(this.scale()/2.0)}. The value of the returned
+      * result is always within one ulp of the exact decimal value for
+      * the precision in question.  If the rounding mode is {@link
+      * RoundingMode#HALF_UP HALF_UP}, {@link RoundingMode#HALF_DOWN
+      * HALF_DOWN}, or {@link RoundingMode#HALF_EVEN HALF_EVEN}, the
+      * result is within one half an ulp of the exact decimal value.
+      *
+      * <p>Special case:
+      * <ul>
+      * <li> The square root of {@code ZERO} is {@code ZERO}
+      * </ul>
+      *
+      * @param mc the context to use.
+      * @return the square root of {@code this}.
+      * @throws ArithmeticException if {@code this} is less than zero.
+      * @throws ArithmeticException if an exact result is requested
+      * ({@code mc.getPrecision()==0}) and there is no finite decimal
+      * expansion of the exact result
+      * @throws ArithmeticException if
+      * {@code (mc.getRoundingMode()==RoundingMode.UNNECESSARY}) and
+      * the exact result cannot fit in {@code mc.getPrecision()}
+      * digits.
+      * @since  9
+      */
+     BigDecimal sqrt(MathContext mc) {
+         return ZERO; // Just the specification for now.
+     }
+ 
      /**
       * Returns a {@code BigDecimal} whose value is
       * <code>(this<sup>n</sup>)</code>, The power is computed exactly, to
       * unlimited precision.
       *