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• is USED to load the class dynamically.
• returns the instance of Class class.
• It should be used if you know the fully qualified name of class. This cannot be used for primitive types. 

Let's SEE the SIMPLE example of forName () method.

class Simple{}

class Test{

public STATIC void main(String ARGS[]){

Class c=Class.forName("Simple");

System.out.println(c.getName());

}

}

Output: Simple

Let's see the simple example of forName () method.

class Simple{}

class Test{

public static void main(String args[]){

Class c=Class.forName("Simple");

System.out.println(c.getName());

}

}

Output: Simple

Following methods of Class class is USED to DETERMINE the class object: 

1. Public Boolean is Interface (): determines if the specified Class object represents an interface type. 
2. Public Boolean isArray (): determines if this Class object represents an array class. 
3. Public Boolean is Primitive (): determines if the specified Class object represents a primitive type. 

Let's see the SIMPLE example of reflection api to determine the object type.

class Simple{}

interface My{}

class TEST{

public static void main(STRING args[]){

try{

Class c=Class.forName("Simple");

System.out.println(c.is Interface());

Class c2=Class.forName("My");

System.out.println(c2.is Interface());

}catch(Exception e){System.out.println(e);}

}

}

Output:

false

true

Following methods of Class class is used to determine the class object: 

Let's see the simple example of reflection api to determine the object type.

class Simple{}

interface My{}

class Test{

public static void main(String args[]){

try{

Class c=Class.forName("Simple");

System.out.println(c.is Interface());

Class c2=Class.forName("My");

System.out.println(c2.is Interface());

}catch(Exception e){System.out.println(e);}

}

}

Output:

false

true

There are 3 WAYS to GET the instance of Class class.

They are as FOLLOWS: 

• forName() method of Class class
• getClass () method of OBJECT class
• the .class syntax

There are 3 ways to get the instance of Class class.

They are as follows: 

Because it has to inspect the metadata in the Bytecode instead of just USING pre compiled addresses and CONSTANTS.

Because it has to inspect the metadata in the Bytecode instead of just using pre compiled addresses and constants.

The java.lang. CLASS class performs mainly two tasks: 

• PROVIDES methods to get the metadata of a class at RUN time.
• Provides methods to examine and CHANGE the run time behavior of a class.

The java.lang. Class class performs mainly two tasks: 

No, It's LIKE CHALLENGING the DESIGN of APPLICATION.

No, It's like challenging the design of application.

The System.Reflection namespace contains types that retrieve information about assemblies, modules, members, parameters, and other entities in managed code by EXAMINING their METADATA. These types also can be used to manipulate instances of loaded types, for example to HOOK up events or to invoke methods.

The System.Reflection namespace contains types that retrieve information about assemblies, modules, members, parameters, and other entities in managed code by examining their metadata. These types also can be used to manipulate instances of loaded types, for example to hook up events or to invoke methods.

System.Reflection. EMIT

System.Reflection. Emit

USE the IsGenericType PROPERTY to DETERMINE WHETHER the type is generic, and use the IsGenericTypeDefinition property to determine whether the type is a generic type DEFINITION.

Use the IsGenericType property to determine whether the type is generic, and use the IsGenericTypeDefinition property to determine whether the type is a generic type definition.

USE MODULE.GetType and Module.GetType to OBTAIN module TYPE OBJECTS.

Use Module.GetType and Module.GetType to obtain module Type objects.

USE Type.GetType to get the Type OBJECTS from an assembly that is ALREADY LOADED Use Type. Get Type to get the Type objects from an assembly that is already loaded.

Use Type.GetType to get the Type objects from an assembly that is already loaded Use Type. Get Type to get the Type objects from an assembly that is already loaded.

USE Assembly.GetType or Assembly.GetType to obtain Type objects from assemblies that have not been loaded, PASSING in the name of the type or types you WANT.

Use Assembly.GetType or Assembly.GetType to obtain Type objects from assemblies that have not been loaded, passing in the name of the type or types you want.

The System. Type class is CENTRAL to reflection. The COMMON language runtime creates the Type for a loaded type when reflection REQUESTS it. You can use a Type object's methods, fields, properties, and nested classes to FIND out EVERYTHING about that type.

The System. Type class is central to reflection. The common language runtime creates the Type for a loaded type when reflection requests it. You can use a Type object's methods, fields, properties, and nested classes to find out everything about that type.

The common language runtime supports multiple programming languages, and the binding rules of these languages differ. In the early-bound CASE, code generators can COMPLETELY control this binding. However, in late binding through reflection, binding must be controlled by customized binding. The Binder class provides custom control of member selection and invocation.

Using custom binding, you can load an assembly at run time, obtain information about TYPES in that assembly, specify the type that you want, and then invoke methods or ACCESS FIELDS or properties on that type. This technique is useful if you do not know an object's type at compile time, such as when the object type is dependent on user input.

The common language runtime supports multiple programming languages, and the binding rules of these languages differ. In the early-bound case, code generators can completely control this binding. However, in late binding through reflection, binding must be controlled by customized binding. The Binder class provides custom control of member selection and invocation.

Using custom binding, you can load an assembly at run time, obtain information about types in that assembly, specify the type that you want, and then invoke methods or access fields or properties on that type. This technique is useful if you do not know an object's type at compile time, such as when the object type is dependent on user input.

BINDING is the PROCESS of locating the declaration that corresponds to a uniquely specified type. When this process occurs at RUN time rather than at compile time, it is called LATE binding.

Binding is the process of locating the declaration that corresponds to a uniquely specified type. When this process occurs at run time rather than at compile time, it is called late binding.

Reflection is USEFUL in the following situations:

• When you have to access attributes in your program's metadata.
• For examining and instantiating types in an assembly.
• For building new types at RUNTIME. USE classes in System.Reflection. Emit.
• For performing late binding, accessing METHODS on types created at run time.

Reflection is useful in the following situations: