OOAD Design for furniture and testing [closed] - oop

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This question was asked in a interview.
A furniture can be made of one or more material. There are various furniture types like chair, table, sofa etc.
A furniture test is dependent on material & furniture type. Few tests are choakable, fire resistable, WithStands100KgWeight etc
Design this in OOAD. The design should follow Open Close principle and should be optimistic such that in future if new furniture is added, it should not need more code change.
Initially suggested with
class Furniture{
List<Material> materials;
boolean supportsTest(Test test);
}
class Chair extends Furniture{
boolean supportsTest(Test test){
// check material and based on type return true/false
}
Interviewer said that a furniture is a furniture, it should not say that it supports this test or not. Any alternative solution? Thanks.

Answer 1

Based on your description and the interviewer's comment, this is what comes to my mind:
// An interface so that it's separate from Furniture class
interface FurnitureTest {
bool IsSupportedBy(Furniture furniture);
}
// Sample test, can add as many as you like
class FireResistable : FurnitureTest {
public bool IsSupportedBy(Furniture furniture) {
return furniture.Type.Name == ! "Mirror" && /* just to use the Type property */
!furniture.HasMaterial(x => x == "Wood");
}
}
///
/// Other class definitions.
///
// Open to extension
class Chair : Furniture { /* additional properties */ }
class Table : Furniture { /* additional properties */ }
// Closed to modification
class Furniture {
public FurnitureType FurnitureType { get; private set; }
private IList<Material> materials;
public Furniture(FurnitureType type, IList<Material> materials) {
this.materials = materials;
}
public bool HasMaterial(string materialName) {
return materials.Any(x => x.Name == materialName);
}
}
class FurnitureType {
public string Name { get; set; }
// ...other properties
}
class Material {
public string Name { get; set; }
// other properties..
}