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Not understand collage starting at a more in-depth level and below that it is the first stage in the

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lifetime of that type.

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And here is the illustration of the class voting process.

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When it is accessed be a class or an interface.

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The classloader objects if the corresponding class object is already on the heap if it is on the heap

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.

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It pre-concert class object.

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Otherwise it means that the pipe is accessed for the very first time.

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So the coroner tries to look kid the corresponding dot class file using something called a zip here

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in delegation moortel which we will discuss next.

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If the doctor find his phone then the classloader loads the corresponding byte Goertz uncreate to a

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class object undercuts it.

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And this class object will be stored on the heap for future use.

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If the Dartmouth's phone is not phone then an exception called class not one exception is thrown.

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If you recall dishcloths voting process was demonstrative and a clips to Grolier were discussing eclipse

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debugger and through it also look at it once again in a demo that we will soon do for Dumont's strict

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in one lifetime of type not a look at board the beat and delegation mortel is which comes into play

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when a pipe is accessed for the very first time.

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As you can see here Jawa has multiple clusters each noting Klaas's Krim different repositories on the

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top.

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We have the bootstrapped Wastwater which is also referred to as primordial classloader underclothes

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.

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All the code just wipe your eyeglasses on this would include the odd Donjon file in the GEORGIS slash

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lib directory.

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On this crossborder is implemented as part of the JVM SAYS.

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Next we have something called the extension classloader which is responsible for the learning process

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from the standard Java extension abs which are in the GRC slash lib slash Yixin directory.

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So much that it was accurate.

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Next we have application or System class order which your application classes from the class bought

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.

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So these are regular classes that we don't post right on below application classloader we have user

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defined clusters.

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That is their custom cross borders created by a regular doper's under used to load classes from nonstandard

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user defined sources like and corrupted files databases and so on.

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These murders are done in Java on Dexter an abstract Glass called classloader which is from the Gelada

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package.

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So user defined Glosson roaders are compiled unordered just like any other object in general most developers

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may never create any custom crossroads object.

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Typically they are done in certain kinds of advanced software like in the case of web servers like Tomcat

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.

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You can see that these cross borders are connected via a parent child relationship and that is every

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classloader except the top one has appeared on the parent delegation more it for locating a class file

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comes from this relationship.

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No when in particular classloader hastily wrote it classify it first console's its period.

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That is it delegates the search irresponsibility brute spirit and that bit it in turn concerns its own

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period and the process continues until the bootstrap cost is reached.

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If the boozed up müssen order does not find a class in its repository then its child which is the extension

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classloader Kreiss Christ defined in its own repository.

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This is where the counter goes downwards under the crossborder that initiated the search.

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So just in its own depositary.

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But if the cross file is found somewhere in between then the corresponding byte Goertz will be loaded

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into memory.

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No the reason why we have this bit in delegation's search model is because JVM considers that repositories

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at the top as more trustworthy compared to the once at lower levels.

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That is bootstrapped last word is repository is considered more trustworthy than extension's glass Lauder's

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repository that just consider more trustworthy than application cluster does depositary.

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If the concern is found in that trustworthy repository then JVM does not perform stringent security

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checks and the verification step in their thinking stage.

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Otherwise JVM performs a strict security checks for instance of the file is found by the application

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Krasnodar then the bytecode verify or performs all kinds of checks as repositories not considered trustworthy

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conduct would not be the case with a cordial IP questions that are considered most trustworthy.

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So we looked at the paid interrogation model which kicks in when it classes access for the first time

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.

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So the next thing is in Vought instances a classes accessed unhandsome loaded for very fast classes

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loaded when an instance of it is created via the new operator.

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It isn't ordered one off its document that is accessed and it is also loaded when one of its toxic fuses

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accessed either reading a value or assigning some value to it.

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Note that accessing compile time constants will not blow declasse and that's because they are compile

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time constants.

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That is their values are known at compile time itself and hence they're copied the word they are used

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.

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So if a different process is using it then the corresponding field value will be copied into that dot

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CROSSFIRE.

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So there's no point loading the class here.

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And this would've been a monster demonstrated in the demo that we will soon do in a couple of lessons

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from now.

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So as long as we are accessing a field that is not a compile time constant then the corresponding class

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will be ordered classes ordered if its subclasses are ordered.

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OK so just keep that in mind.

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And the class is obviously loaded.

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If it does run from the command line finally it can also be loaded with reflection on we were discuss

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reflection and few lessons from now.

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So those are the instances when a class is loaded for the very first time.

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Now when it comes to an interface except for the Fuster isn't an interface Voula also be loaded in all

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other instances with regards to the first reason.

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We know that we cannot instantiate an interface just know of second instance is possible only from July

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8 onwards.

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As part of Java aid interfaces cannot house start it matters on for the same reason an interface can

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be run from the command line also.

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And that's possible only from July 8 onwards and that's because the main method is this tactic method

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.

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So the interface can have a main method.

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Finally an interface can also be loaded when a sub interface is loaded.

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In addition to suppress the class it can only be a subclass as it cannot have a sub interface that is

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an interface cannot ekster Nicholas.

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No let's discuss a little bit about a class object which is the output of the class throating process

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unladen we would have more effort while coding reflection the most important thing to know is that all

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the objects that we create from a particular class is always done using the class object of ductless

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and that's how GBM creates objects for us.

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It's not just class an interface that would have a class object.

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Even all primitive types.

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The void keyword on our base would have a class object later when doing a dim off reflection B would

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see hope class object also Madieu will be useful on with regards to our is.

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Note that all R is of same dimension n same type.

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Have the same class object lenth of the R It does not play any at all here.

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For example an entry of entry has the same class object as and array of Lent hundred since both out

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of pipe in unbought have the same number of dimensions.

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Gas object basically contains Medine for mission aboard the class and we can get that information using

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its methods on some of them are shown here.

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The first method name would simply written the name of the class get superclass method worked on the

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superclass of the current class so that it can bite is the class object of the code I'm closer to possess

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either.

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Object class or an interface or a primitive type or void.

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Then null is returned as they don't have a superclass.

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If this class object represents an array class then the class object representing the object lost is

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returned.

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Next is the user interface muttered under detainments of the current class object represents an interface

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not Nexus get interface estimate.

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Underachieve does all the interfaces implemented by the current class and get frustrated a third rate

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and that classloader that loaded this class under-exposed more interesting methods.

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In the dim off reflection I think you can check out all the methods in a game.

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Once we do that Demel so up with the class throwing process.

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We looked at the class learning process itself.

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We looked at class loaders and also the bean in delegation model which happens when a class has access

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for the very first time.

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And we also looked that instances when a type is access for the very first time and finally we looked

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at the class object itself.

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Thank you