public static Expression castIfNecessary()

in src/main/java/net/hydromatic/linq4j/expressions/Types.java [432:466]

23 lines of code
10 McCabe index (conditional complexity)


  public static Expression castIfNecessary(Type returnType,
      Expression expression) {
    final Type type = expression.getType();
    if (Types.isAssignableFrom(returnType, type)) {
      return expression;
    }
    if (returnType instanceof Class
        && Number.class.isAssignableFrom((Class) returnType)
        && type instanceof Class
        && Number.class.isAssignableFrom((Class) type)) {
      // E.g.
      //   Integer foo(BigDecimal o) {
      //     return o.intValue();
      //   }
      return Expressions.unbox(expression, Primitive.ofBox(returnType));
    }
    if (Primitive.is(returnType) && !Primitive.is(type)) {
      // E.g.
      //   int foo(Object o) {
      //     return ((Integer) o).intValue();
      //   }
      return Expressions.unbox(
          Expressions.convert_(expression, Types.box(returnType)),
          Primitive.of(returnType));
    }
    if (!Primitive.is(returnType) && Primitive.is(type)) {
      // E.g.
      //   Short foo(Object o) {
      //     return (short) (int) o;
      //   }
      return Expressions.convert_(expression,
          Types.unbox(returnType));
    }
    return Expressions.convert_(expression, returnType);
  }