Reflections (toc or index)

Before we being reflections we should note the following:

Note of caution for reflection

Now we can proceed further.

Examining Classes

Following is required to examine a class:

Retrieving Class Objects
First things first. Before you can find out anything about a class, you must first retrieve its corresponding Class object.

Getting the Class Name
It's easy to find out the name of a Class object. All you have to do is invoke the getName method.

Discovering Class Modifiers
This section shows you the methods you need to call to find out what modifiers a particular class has.

Finding Superclasses
In this section you'll learn how to retrieve all of the Class objects for the ancestors of a given class.

Identifying the Interfaces Implemented by a Class
If you want to find out what interfaces a class implements, then check out this section.

Examining Interfaces
In this section you'll learn how to tell if a Class object represents an interface or a class. You'll also get some tips on how to get more information about an interface.

Identifying Class Fields
This section shows you how to discover what fields belong to a class, and how to find out more about these fields by accessing Field objects.

Discovering Class Constructors
This section, which introduces the Constructor class, explains how to get information about a class's contructors.

Obtaining Method Information
To find out about a class's methods, you need to retrieve the correspondingMethod objects. This section shows you how to do this.

Manipulating Objects

Software development tools, such as GUI builders and debuggers, need to manipulate objects at run time. For example, a GUI builder may allow the end-user to select a Button from a menu of components, create the Buttonobject, and then click the Button while running the application within the GUI builder. If you're in the business of creating software development tools, you'll want to take advantage of the reflection API features described in this lesson.

• Creating Objects
  How can you create an object if you don't know its class name until run time? You'll find the answer in this section.
• Getting Field Values
  In this section you'll learn how to get the values of an object's fields, even if you don't know the name of the object, or even its class, until run time.
• Setting Field Values
  Not only can you get field values at run time, you can also set them. This section shows you how.
• Invoking Methods
  This section shows you how to dynamically invoke methods. Given an object, you can find out what methods its class defines, and then invoke the methods.

Creating Objects

• Using No-Argument Constructors
• Using Constructors that Have Arguments
• Getting Field Values
• Setting Field Values
• Invoking Methods

Working with Arrays

• Identifying Arrays
• Retrieving Component Types
• Creating Arrays
• Getting and Setting Element Values

Summary of Classes