Why doesn’t java.lang.Object implement the Serializable Interface? [duplicate]

Potential security hole All subtypes of a serializable class are themselves serializable. In other words: all classes you ever create, were or will be created are all serializable. transient only excludes fields, not whole classes. This is a potential security hole – by coincidence you can serialize e.g. your DataSource with database credentials inside – … Read more

Penalty to implement Serializable in Java?

There is no performance impact unless you perform serialization/deserialization but there are trade offs in terms of api design. From Effective java by Joshua Bloch A major cost of implementing Serializable is that it decreases the flexibility to change a class’s implementation once it has been released A second cost of implementing Serializable is that … Read more

Cannot pass custom Object in an Intent: The Method Put Extra is Ambiguous for the type Intent

The first error: ‘The Method Put Extra is Ambiguous for the type Intent’. The class Car is both Serializable and Parcelable, the compiler doesn’t know whether to use putExtra(Serializable s) or putExtra(Parcelable p) to handle your request. So you have to cast your Car to one of them when using Intent.putExtra(). Intent.putExtra(“car”, (Parcelable)myCarObject); Intent.putExtra(“car”, (Serializable)myCarObject); … Read more

Portable class library: recommended replacement for [Serializable]

Portable Class Libraries (PCLs) now officially deprecated [16 August 2017] If you’re sharing code between different .NET implementations today, you’re probably aware of Portable Class Libraries (PCLs). With the release of .NET Standard 2.0, we’re now officially deprecating PCLs and you should move your projects to .NET Standard. Source: Announcing .NET Standard 2.0 Portable Class … Read more

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