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Let's begin by looking at Dodik matters which very briefly discussed when introducing methods well into

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using methods these methods can be of two types.

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One is.

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Instance Well the other is static doorways.

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Object oriented.

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And so most of the time methods invoke Bill which state that is.

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Instance variables such methods are the instance matters but sometimes we also implement utility methods

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that do not depend on state on such matters are defined as tactic.

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An example would be the min method from the class Jawa Dr. Lang dogmatic which is a class that provides

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several utility methods for performing mathematical operations.

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Not that a class can how only instance are only static methods or it can how both of them started motets

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have the keyword static in them at their declaration.

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Absence of static the word implies it's an instance method.

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Main method is an example of a static method.

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In fact all the matters to be brought so far in our BASIX democracy are static matters.

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Startlement that's a plasma.

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There there is as I mentioned earlier unlike instance methods they don't build with objects.

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That is they don't have access to either instance variables or instance methods trying to access them

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from a static method generates a compiler.

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However they can access static variables if you recall static rebels or class global variables.

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That is they are also not object specific a static variable declared in a class is shared across all

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objects of that class.

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Since started methods don't have anything to do with it.

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They can be accessed other static methods in the same class since they are plausible amateurs.

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They can be invoked using a dart operator on the class name for example invalid Amendment.

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In the math class.

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You will simply do math Trotman and it would also save heaps because as you don't have to create an

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object laundered it is legal to invoke a static method on a reference variable.

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But it leads to misleading code as reference variables are associated with objects.

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So it's not recommended to invoke a static method using a reference variable.

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And even if you do compiler would implicitly resolve it back to class name next is an effective item

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and it has item for under-dressed enforce non intangibility with a private constructor.

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Basically if all methods in your class will be static then you can make the class non-instructional

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by marking its constructor as by weight.

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So if you make the concept of by private that no other code can create an object of your class.

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And that would also save some heaps because dollar not Langbroek Matt is implemented this way.

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Which means that we cannot create an instance of the math class.

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Let's actually look at this by revealing the source code of the math class.

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Then what I want to explore source code I use this site called a core I simply google for grep or under

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a particular class I want to explore.

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So let's do that.

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So let's search her grep code under map class.

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Let's just type in math here.

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So this is the fosterling listeners just click dot.

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And here it shows the code for my class.

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So basically grep God is a search engine that has in several libraries including JDK and it basically

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allows us to browse through these libraries for JDK they index something called Open Jilek which is

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an open source version of Judy and it is almost identical to articles JDK.

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So you should be able to explore this code without any assumptions.

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So let's just look at this math class that we have here.

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So it's the actual source code and here it says open Judy key and it's one of this I think it's one

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of the six point oceans jealous ex Mercians but that's fine.

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And let's click on this.

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This is the constructor here you can see the constructor and all the methods in the math class.

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OK.

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So let's just click on this.

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Here is the constructor and it says it has a pirate modifier which means that it is non instantiation

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.

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Right.

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And here are all the different methods that we have.

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And here is one of them at the men.

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Let's just go ahead and click that.

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It's an overloaded method and here as this tactic modifier which means that it is a static method.

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And as we know all the materials in the math class are static metrics and if you click despondence and

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don't idle it shows as all the usages all the classes that are using this particular mean matter.

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For example string class is using the amendment from this particular matter called compared to.

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And here is how another class called Jawad or RSA which is also using it in a medical sort.

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One is is also like math class.

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It has a private constructor.

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So it is also a non intangible.

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And these are some other amateurs.

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Some other classes that are using them in matter and that's supported regarding the Gruppe so you can

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use it to explore any particular classes that you want to explore and you can also do one more thing

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if you don't want to use this.

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You can actually search I mean to adjudicate that you don't order it also comes with the sourcecode

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.

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So let me just short you on my machine.

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So this is the root directory of my JDK which is the day to get one point eight.

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So I just went into program files Java JDK 1.8 and here you can see this zip file called SIAC and it

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has the source code.

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So you just need to unzip it.

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I have also done that and I just extracted only one of the directories which is Jawa it has a few others

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.

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The zip file has a few other directories but I just exported only one of them.

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So here it is the Jawa.

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So you're going to Jawa.

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So these are the different folders.

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Like the job line or two line packages here.

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So just going to lying.

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And then you can see all the glasses here.

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Here is my door Jawa and I can just edited and it's the same thing.

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I can explode the code so you can either do this or you can explore the grep go to that site.

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And that's about it.