static Type gcd()

in src/main/java/net/hydromatic/linq4j/expressions/Types.java [384:421]

• 33 lines of code
• 11 McCabe index (conditional complexity)

  static Type gcd(Type... types) {
    // TODO: improve this
    if (types.length == 0) {
      return Object.class;
    }
    Type best = types[0];
    Primitive bestPrimitive = Primitive.of(best);
    if (bestPrimitive != null) {
      for (int i = 1; i < types.length; i++) {
        final Primitive primitive = Primitive.of(types[i]);
        if (primitive == null) {
          return Object.class;
        }
        if (primitive.assignableFrom(bestPrimitive)) {
          bestPrimitive = primitive;
        } else if (bestPrimitive.assignableFrom(primitive)) {
          // ok
        } else if (bestPrimitive == Primitive.CHAR
                   || bestPrimitive == Primitive.BYTE) {
          // 'char' and 'byte' are problematic, because they don't
          // assign to each other. 'char' can't even assign to
          // 'short'. Before we give up, try one last time with 'int'.
          bestPrimitive = Primitive.INT;
          --i;
        } else {
          return Object.class;
        }
      }
      return bestPrimitive.primitiveClass;
    } else {
      for (int i = 1; i < types.length; i++) {
        if (types[i] != types[0]) {
          return Object.class;
        }
      }
    }
    return types[0];
  }