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It does them all for the affliction.

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We have two classes.

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One is called the refl. demo and it is a main class on has been appropriately named I and the other

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one is called as a user of dot Jawa.

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So both of these classes are either in the GBM package so refl. do more as a main class and written

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refl. them or we have the main method.

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And there are things that we are testing here.

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So there are two methods for Budapest's one is called as demo class object access.

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So as the name suggests this particular method is used to demonstrate accessing class object so there

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were three ways to access class objects.

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Unreal.

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And we'll be looking at all three of them and we will also see how the Mad-Eye information in the class

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object can be accessed.

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And the second method is Karlos demo code reflection.

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And here we will explore more reflection properties for reflection features.

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So we will demonstrate instance creation and method invocation using the class object.

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So the class object.

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Here is the input.

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So that's what we are going to test here and use and our July is pretty simple.

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We are already familiar with this class so it has all these fields and it has no constructor and it

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also has this constructor which has all these parameters on initialises the fields and there are two

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methods.

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One is called a save weblink and the other is both bookmark review with some parameters here.

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But let's not worry about all of that because that's not relevant here.

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And just wandered into Boullion.

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So let's go back.

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So both these classes are available in the resource section for download.

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So let's just look at what we have in each of these matters.

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So let's just go here first with a demo class object access.

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So the first one as accessing the class object via object reference.

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So for this we are defining this string array object and it has these three values.

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And all we are doing is just invoking since a and is also an object in Java we are invoking the get

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class method and we are just simply printing or to get name.

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Now the second thing we are testing is the Arctic farming method and the class.

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So we are passing the fully qualified name here.

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After that off the user class which is also in JVM.

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So we are passing the fully qualified name on we are loading the class and we are printing all the information

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at least some of the important ones like what did we miss with that it's an interface or not.

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If there are any interfaces that this particular class user is in stone is implementing.

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And also the superclass here getting the superclass off user and printing its name.

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OK.

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Now the third one here there is one additional test that we are doing.

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We know that Glassdoor foreign for named does not work with primitives.

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So here we have a primitive here here and this word at runtime.

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This would throw an exception called class not one exception as was discussed.

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So the congruity comes here and brings this message.

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And finally there Doc class the class nutritious approaches tested here so we ain't dog class which

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is a class object and we are simply printing the name.

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So that's the first method and here is a second letter to the second method we are placing a class object

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here.

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So we are getting the class object using the foreign name approach and we are simply passing it here

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.

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And all we are doing is we are creating a new instance here.

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So on the class object this object we are calling this method call new instance.

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And in order to do that the user class must have a default constructor and that's the reason for having

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this constructor here.

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It should be there.

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Now once we do that we are invoking this method Corylus get declared methods and it contains all the

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methods in the class.

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OK.

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And so I couldn't send off all the method objects or here and method object is from the dot dot Langhart

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reflect package.

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And we are printing the names.

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And here we are making use of the white glass object.

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So we are simply saying why not glass.

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And if this particular method in the in the current iteration if it has we are calling the return type

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method and get returned by returns that the class object corresponding to the return type and if it

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equals the white class or a wider class which means that the class object responding to why don't we

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simply print dispatch it message method or can type as wide.

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So one of the methods has a void.

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It can type on in here get declared constructors.

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So disorder gets on the constructors and each construct it is basically an object.

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Once again from the Java Langhart reflect.

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And here we are getting one particular constructor.

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The constructor that does that for fetching is based on the number of barometers and the type of the

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parameters and basically the be on the type of the parameters.

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So if you look at this etches get declared constructor has an array of class objects are being passed

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here.

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OK.

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So it's a virus parameter.

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So based on that we get the constructor that we need and then we are creating a new instance of that

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.

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And we are passing all the values for example here it is anti-abort glass.

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The first parameter so we are passing this value 101 on the second parameter is name that Hurleys email

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.

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And so we are passing all the corresponding values that we need to pass.

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And here we are fetching a method and invoking it.

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So previously we are fetching a concept around in working it.

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Here you are fetching a method only milking it.

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And all we do is we in the matter get declared method on the class reference variable and we are saying

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that we need this method call see weblink and we are also specifying the parameter types here.

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String not grass.

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Another one is string dark glass.

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So if you go back here has string parameters.

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So that's what we are saying we need that particular method.

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OK so this get declared better.

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As for getting one particular matter get declared constructor as for fetching one particular constructor

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and the way you walk and method is.

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So you have the method object here just call in matter and you need to pass this user object.

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You need to pass this use object that was created earlier and we need to pass the values also.

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So we are passing.

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Do I use one of them as the host name and the other one as say rebeling is some idea.

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Sorry that you are an Teicher.

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So you're passing those values here.

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And this is returning some value.

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So Doc ralliers are off and working that is being printed here.

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So that's about it here.

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So let's just go ahead and run this program and look at the values too.

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So let's look at this.

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So here it is.

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We are printing this.

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This is using the Glasman getting the class object we are the object reference and object reference

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is basically a string array.

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So it's printing the name.

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So this is the name that's getting printed.

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So since it's an array single dimension an array we have this squared record.

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And since it's a string that it contains.

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So we have this string class preceded by an L as mentioned earlier and a semicolon.

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So that's the first one.

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Next we are using the start for a new method.

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And we are leading the class here and we are printing the name here.

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Class not get me.

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Which gives the name of the fully qualified name off the user class.

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Is it an interface.

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No number of interface it implements.

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No it doesn't implement any interfaces.

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And what is a superclass superclass is there is only one class which is it's not excluding any other

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class.

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So the only class it extends as the object bus underspending its name here.

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Now here we are trying to load a primitive using for name which we know doesn't work.

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So the control goes into the catch block here and brings this message glass not found exception to class

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dart for me not get me.

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So that's just one type of message.

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And here we are printing using the class to access the class object and we are printing its name.

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And here it is.

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It just prints it.

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That's it because it's a primitive.

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Know let's move into the second method which is a demo called reflection.

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And here a new object is created.

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And so the object name the variable name is object.

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And we are getting we are getting it's get using get Glasby and getting the class object and we are

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once again simply printing it.

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OK.

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So for I'm the class object we are creating an object.

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But then from the object we are getting the class object one more time.

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And just printing its name just to demonstrate all of this.

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So if you go down here which says object don't get class as this is the name of the class of this particular

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object.

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Now let's.

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Next as we have printing out all the methods shown here are declared methods and they are ignoring the

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get named method here.

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So it's printing to matter say a weblink was bookmark review.

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OK.

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And one of the methods post-Bush Marco Rubio has

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a right as the return type.

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So it goes into this if condition this if statement executes.

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It has a true value and it prints this statement.

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Next is we are printing all the constructors and we are breaking the name.

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Name is simply the user here for both of them are numbered alphabet I mean girls.

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So there is a method called Get barometer types on in where we are invoking that document.

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So on the first iteration or just the default constructor and the second it's the second constructor

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which had five parameters.

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And finally here we are invoking the method we are creating an instance using the instance of user using

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it using this constructor and then we are also getting though the method.

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This particular method called Save eyeblink and invoking it but passing the user instance here.

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And so it has this particular method has some print statements on it's getting printed and simply printing

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older the values passed here the parameter values.

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And finally the result of invoking save eyeblink that it can take is basically a boolean and it truly

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is getting printed here.

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So that's about that's about the reflection the more that we have.

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And one thing I want to mention as a reflection is definitely slower compared to non-HD reflection court

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.

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So for example if you're creating an all if you're creating objects using reflection and if you also

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compare it if you create the same object be it using non-HD reflection.

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So you're using the new Nuki keyword then definitely in the non-definition code will be slightly faster

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but a reflection is also useful.

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It needs to be used but it's just that it is a bitch.

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It is kind of slower.

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And so you want to be really careful if your code is going to be frequently used and you have and you

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have the reflection code there.

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So if it is being used in a very frequently used code and application or surface performance intensive

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then you need to be careful about that.

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Maybe you don't want to use Reflection in those parts of the code.

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So so just to exercise caution be careful.

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OK so that's about it.

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So that's refl. demo and we have a strict pretty much everything that we have learned.

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Thank you.

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And happy coding.