C#


CSHARP.CLASS.CLONE.CNC : clone Non-cloneable (C#)

Summary

Method Clone() is defined in a non-cloneable class.

This checker identifies frequent problems in the definition of the method Clone(). That method is used to generate a clone of an object, that is, a distinct instance with the same behavior as the original one. The default implementation in System.Object checks that the object to clone implements the interface System.ICloneable or otherwise throws an exception. Hence, in order to clone an object it is in general enough to implement that interface and use the default implementation of Clone(). It is also possible to override that default implementation. Note that a class that inherits the default implementation allows its subclasses to implement System.ICloneable and clone its instances.

Properties

Class Name clone Non-cloneable (C#)
Significance reliability
Mnemonic CSHARP.CLASS.CLONE.CNC
Categories
CWE CWE:491 Public cloneable() Method Without Final ('Object Hijack')
Availability Available for C# only.
Enabling Checks for this warning class are enabled by default. To disable them, add the following WARNING_FILTER rule to the project configuration file.
WARNING_FILTER += discard class="clone Non-cloneable (C#)"

Example

namespace DocumentationExamples
{

    public class Clone1
    {
        public static void Main(string[] args)
        { }

        public object Clone()             // "clone Non-cloneable (C#)" warning issued here
        {
            return new Clone1();
        }
    }
}

Resolution

Check that Clone() is only redefined in classes that implement System.ICloneable. Check that the default implementation of Clone() is only used for classes that have explicitly declared to implement System.ICloneable.

Relevant Configuration File Parameters

The following configuration file parameters affect checks for this warning class.