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Generics
Introduction
Generic Types
Generic Methods and Constructors
Bounded Type Parameters
Subtyping
Wildcards
Type Erasure
Summary of Generics
Questions and Exercises
Trail: Learning the Java Language
Lesson: Generics

> Generics are a built-in language feature that will make your software more reliable. This lesson discusses the following topics:

> ### Introduction

> > This section explains some common shortcomings associated with non-generic code. Specifically, it shows how certain kinds of bugs will crash an application at runtime, since they are not detectable by the compiler.

> ### Generic Types

> > This section explains generic type declarations, type variables, type parameters, and type arguments. It also describes the naming conventions that are specific to generics.

> ### Generic Methods and Constructors

> > This section shows how type parameters can be used to define generic methods and constructors.

> ### Bounded Type Parameters

> > This section describes how type parameters can specify an upper bound that limits the kind of types that can be passed in.

> ### Subtyping

> > This section describes how generic subtyping differs from non-generic subtyping.

> ### Wildcards

> > This section continues the discussion of subtyping by describing bounded and unbounded wildcards.

> ### Type Erasure

> > This section describes type erasure, raw types, and unchecked warnings.

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