{"id":8724,"date":"2022-09-15T05:23:08","date_gmt":"2022-09-14T23:53:08","guid":{"rendered":"https:\/\/jassweb.com\/solved\/solved-what-do-you-call-this-object-in-java-and-why-do-you-use\/"},"modified":"2022-09-15T05:23:08","modified_gmt":"2022-09-14T23:53:08","slug":"solved-what-do-you-call-this-object-in-java-and-why-do-you-use","status":"publish","type":"post","link":"https:\/\/jassweb.com\/solved\/solved-what-do-you-call-this-object-in-java-and-why-do-you-use\/","title":{"rendered":"[Solved] What do you call this object in Java and why do you use?"},"content":{"rendered":"

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I have some trouble understanding your English, so I might have misinterpreted some of your questions.<\/p>\n

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What do you call this object in Java and why do you use?<\/p>\n<\/blockquote>\n

I don’t know which “object” you are referring to.<\/p>\n

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… yet still don’t know why is this<\/code> possible and what this<\/code> is called. <\/p>\n<\/blockquote>\n

It is just called this<\/code>. There is no other term for it.<\/p>\n

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Class variable? <\/p>\n<\/blockquote>\n

No. this<\/code> is not a class variable.<\/p>\n

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Objects creating objects? <\/p>\n<\/blockquote>\n

(Huh?) No. this<\/code> is not “objects creating objects”.<\/p>\n

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And in the setter method, why the default value is null? <\/p>\n<\/blockquote>\n

Because that is the way that Java defined. Any instance variable (like item<\/code>) whose type is a reference type<\/em> has a default initial value of null<\/code>.<\/p>\n

(Why? Because that is the only value that makes sense from a language perspective. Anything else, and there would need to be some way for the programmer to say what the default is. Compilers can’t read your mind!)<\/p>\n

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is it like String? <\/p>\n<\/blockquote>\n

Not sure what you mean. But if you are asking if you would get the same default value behavior if item<\/code> had been declared with type String<\/code>, then Yes.<\/p>\n

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From what I’m assuming, RetailItem item<\/code> is like it combined the whole RetailItem<\/code> class and creating a new variable in another class with its feature. <\/p>\n<\/blockquote>\n

Not exactly. What RetailItem item<\/code> is actually doing is declaring a variable<\/em> in which you may then put a reference to a RealItem<\/code> object. This variable has the default value null<\/code> …. until some other value is assigned to it.<\/p>\n

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What does item = new RetailItem();<\/code> mean?<\/p>\n<\/blockquote>\n

That means create (construct) a new RetailItem<\/code> instance (an object), and then assign its reference to the variable item<\/code>.<\/p>\n

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I don’t know where am I even going to start studying.<\/p>\n<\/blockquote>\n

I recommend that you start with a good introductory Java textbook, or the Oracle Java Tutorial, or your course lecture notes. Ask your teachers.<\/p>\n

But keep at it. If you work at it, you will get to the point where it all starts to make sense. Because, basic Java is a simple and consistent language. The language only gets complicated when you learn about generics, type inference \/ lambdas and …. multi-threading.<\/p>\n<\/p><\/div>\n

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2<\/span> <\/p><\/div>\n<\/div>\n

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solved What do you call this object in Java and why do you use? <\/p>\n","protected":false},"excerpt":{"rendered":"

[ad_1] I have some trouble understanding your English, so I might have misinterpreted some of your questions. What do you call this object in Java and why do you use? I don’t know which “object” you are referring to. … yet still don’t know why is this possible and what this is called. It is … Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[320],"tags":[323],"class_list":["post-8724","post","type-post","status-publish","format-standard","hentry","category-solved","tag-java"],"yoast_head":"\n[Solved] What do you call this object in Java and why do you use? - JassWeb<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/jassweb.com\/solved\/solved-what-do-you-call-this-object-in-java-and-why-do-you-use\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"[Solved] What do you call this object in Java and why do you use? - JassWeb\" \/>\n<meta property=\"og:description\" content=\"[ad_1] I have some trouble understanding your English, so I might have misinterpreted some of your questions. 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