guava/src/com/google/common/math/IntMath.java
public static int checkedPow(int b, int k) {
    checkNonNegative("exponent", k);
    switch (b) {
      case 0:
        return (k == 0) ? 1 : 0;
      case 1:
        return 1;
      case (-1):
        return ((k & 1) == 0) ? 1 : -1;
      case 2:
        checkNoOverflow(k < Integer.SIZE - 1, "checkedPow", b, k);
        return 1 << k;
      case (-2):
        checkNoOverflow(k < Integer.SIZE, "checkedPow", b, k);
        return ((k & 1) == 0) ? 1 << k : -1 << k;
      default:
        // continue below to handle the general case
    }
    int accum = 1;
    while (true) {
      switch (k) {
        case 0:
          return accum;
        case 1:
          return checkedMultiply(accum, b);
        default:
          if ((k & 1) != 0) {
            accum = checkedMultiply(accum, b);
          }
          k >>= 1;
          if (k > 0) {
            checkNoOverflow(-FLOOR_SQRT_MAX_INT <= b & b <= FLOOR_SQRT_MAX_INT, "checkedPow", b, k);
            b *= b;
          }
      }
    }
  }
public static int checkedPow(int b, int k) {
    checkNonNegative("exponent", k);
    switch (b) {
      case 0:
        return (k == 0) ? 1 : 0;
      case 1:
        return 1;
      case (-1):
        return ((k & 1) == 0) ? 1 : -1;
      case 2:
        checkNoOverflow(k < Integer.SIZE - 1, "checkedPow", b, k);
        return 1 << k;
      case (-2):
        checkNoOverflow(k < Integer.SIZE, "checkedPow", b, k);
        return ((k & 1) == 0) ? 1 << k : -1 << k;
      default:
        // continue below to handle the general case
    }
    int accum = 1;
    while (true) {
      switch (k) {
        case 0:
          return accum;
        case 1:
          return checkedMultiply(accum, b);
        default:
          if ((k & 1) != 0) {
            accum = checkedMultiply(accum, b);
          }
          k >>= 1;
          if (k > 0) {
            checkNoOverflow(-FLOOR_SQRT_MAX_INT <= b & b <= FLOOR_SQRT_MAX_INT, "checkedPow", b, k);
            b *= b;
          }
      }
    }
  }
Returns the {@code b} to the {@code k}th power, provided it does not overflow.

<p>{@link #pow} may be faster, but does not check for overflow.

@throws ArithmeticException if {@code b} to the {@code k}th power overflows in signed {@code
int} arithmetic