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Hi Everyone interesting story all I want to talk about this story in class in Java.



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So first of all we need to create a Java project.



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So we need to click on File New and then click on Java project.



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OK.



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So for the project name just type in here.



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A strange class.



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OK.



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And then click on finish and then if we need a main class for our project.



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So just click on this as our See folder and then click on File New and then click on class.



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So for the class name just type in here made and for the package name we need a reverse domain here.



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So just type in here com that your name dot project name is three in class.



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OK.



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And for the modifiers to publish and here make sure that you check this check box here that says public



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static void main effect.



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OK.



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And then click on finish.



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So as you can see here our main class is now created.



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So just delete this comment here and then I double click on this main Java tab here in order to make



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this a little area wider.



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So as you can see here my editor area is now much wider.



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So now I want to talk about a predefined class in Java called string.



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Ok so what is strange strange is nothing but a sequence of characters.



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For example hello is a string of five characters in Java programming language.



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Strange is an immutable object which means it is constant and can not be changed once we actually created



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that object.



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OK first of all in order to create our screened there are two ways.



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The first way is string literal and the second way is using the new keyboard.



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OK so the first way is strangely the road in Java strings can be created by assigning a string literal



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to a string instance.



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OK so now let me show you some real examples about strings.



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OK.



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So first of all in order to create a string object first we need to refer to the name of our string



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class as strange as you can see here.



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And then if we need to give our object a name for example my first strange.



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OK.



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And then we need to put in an assignment operator here and then we need to actually assign a string



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literal to our string object.



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OK.



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So I just need to put in here to double quotes and insert the double quotes.



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I can just typing Hello.



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OK.



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And then I need to put in a semi-colon at the end of my statement.



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So now as you can see I created a string object called my first string and I assigned this string literal



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to our string object.



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OK.



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So in order to actually create String objects we need to actually put use these double quotes and inside



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the double quotes.



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We can just put our string literals.



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So remember that string object is nothing but a sequence of characters.



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OK so now if I want to output the value of this string object to the console I just need to type in



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here system that out that princeling.



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And then inside the prentices I can just refer to the name of my object my first strange and then I



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need to put in a semi-colon at the end of my statement.



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So now if I run my project let's see what happens.



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As you can see this value is now output to the console.



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Hello.



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OK.



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So this value is the value of this string object.



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OK so now let me actually create another string object.



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So again I need to refer to the name of my class as strange.



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OK.



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And then I need to give my object a name.



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My second string.



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OK.



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And then I need to put in an assignment operator here and then I put in double quotes and then inside



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the double quotes again I type in Hello OK and then I need to put in a semi-colon at the end of my statement.



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And now if you want to output the value of my second string object to the concert I just need to type



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in here system that out that print learned and it inside the parenthesis I can just refer to the name



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of my object my second string object.



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And then I need to put in a semicolon at the end of my statements.



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So as you can see here now this value is output to the console.



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And as I said earlier in the section this for example this my second string doesn't hold this hello.



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Object here.



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This my second string only actually contains the address of this object in memory.



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OK so this is how our objects are actually saved in memory.



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But for primitive data types for example our primitive data types like int and for example the name



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of my value is a.



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And then I can assign a value to my value.



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But here is a valuable actually holds this number free wheeling it.



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OK.



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But this my second string actually contains the address of this hello object in memory.



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OK.



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In other words this my second string is actually a pointer to this.



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Hello.



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Object in memory.



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Ok so now let me actually show you another important point about objects in memory.



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So as you can see here I have 10 string objects here.



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OK.



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So now as you can see here I assigned the same value to all of these 10 String instances.



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OK.



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So as you can see here for example for my first string instance I assigned the word hello to my first



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string instance.



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OK.



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Or for example for my second string instance I assigned the word Hello.



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OK.



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And for all of my 10 string instances here I assigned the same word hello to all of these string instances.



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How this object is actually saved in memory.



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So because we actually have 10 strange instances here with this same value the compiler is only actually



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create one object which as you can see here divorce.



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Hello.



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And it's going to actually assign the address of this object in memory to all of these 10 string instances.



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OK.



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So for example my first string instance actually holds the address of the hello object in memory or



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my second string instance actually holds the address of the hello object in memory.



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Or in other words these string instances actually point to the hello object in memory.



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OK.



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So that's it that's how actually the objects are actually saved in memory.



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When you actually create String objects by using string literals.



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OK but if you actually for example change the value of one of these string instances to another value



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that string instance going to actually hold another address for that specific object.



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OK but if you have actually the same value for your string instances the compiler is going to actually



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create only one object and that is going to actually hold the address of that object to those string



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instances.



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So now let me actually show you some real examples in order to make this concept more meaningful for



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you.



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OK so now if you go back inside the eclipse as you can see here these two objects this my first string



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object and this my second string object have actually the same value.



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OK so the compiler is going to actually create only one object and then it's going to actually hold



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the address of that object inside.



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Inside of these string instances.



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OK.



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So now if I for example change the value of my first string object to another value of i need to refer



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to the name of our object.



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My first strange and that I need to put in an assignment operator here and then I actually change the



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value hello to HI.



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Okay.



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And then I need to put in a semi-colon at the end of my statement.



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So as you can see here now if I want to output the value of the first string object to the console I



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just need to type in here system that out that princeling and it inside the parenthesis.



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I can just refer to the name of my object my first strange and then I need to put in a semicolon at



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the end of my statement.



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So now if I had on my project as you can see this value is now output to the console.



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OK so now the address of this object is actually is actually reading this my first string object.



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OK this object is inside another place is in the memory.



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And that address is inside of this my first string instance.



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OK.



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It's my first string instance actually holds the address of this object inside the memory.



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And this my second string object actually holds the address of this object.



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Hello.



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Inside the memory.



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OK.



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So now if you want to output the value of the second string object to the console.



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Let's see what happens.



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System that out that prints learn and then inside the parenthesis I can just refer to the name of my



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my second string object.



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And then I need to put in a semi-colon at the end of my statement.



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So as you can see this value Halo is now outputted with the consular kit.