Java Encapsulation and Getters and Setters - W3Schools

... CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more. ... private = restricted access // Getter public String getName() { return name; } ... 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GetandSet Youlearnedfromthepreviouschapterthatprivatevariablescanonlybe accessedwithinthesameclass(anoutsideclasshasnoaccesstoit).However, itispossibletoaccessthemifweprovidepublicgetandsetmethods. Thegetmethodreturnsthevariablevalue,andthesetmethodsetsthevalue. Syntaxforbothisthattheystartwitheithergetorset,followedbythe nameofthevariable,withthefirstletterinuppercase: Example publicclassPerson{  privateStringname;//private=restrictedaccess  //Getter  publicStringgetName(){    returnname;  }  //Setter  publicvoidsetName(StringnewName){    this.name=newName;  } } Exampleexplained Thegetmethodreturnsthevalueofthevariablename. Thesetmethodtakesaparameter(newName)andassignsittothe namevariable.Thethiskeywordisusedtorefertothecurrent object. However,asthenamevariableisdeclaredasprivate,we cannotaccessitfromoutsidethisclass: Example publicclassMain{  publicstaticvoidmain(String[]args){    PersonmyObj=newPerson();    myObj.name="John"; //error    System.out.println(myObj.name);//error   } } RunExample» Ifthevariablewasdeclaredaspublic,wewouldexpectthefollowingoutput: John However,aswetrytoaccessaprivatevariable,wegetanerror: MyClass.java:4:error:namehasprivateaccessinPerson     myObj.name="John";          ^ MyClass.java:5:error:namehasprivateaccessinPerson     System.out.println(myObj.name);                   ^ 2errors Instead,weusethegetName()andsetName()methodstoaccessandupdatethevariable: Example publicclassMain{  publicstaticvoidmain(String[]args){    PersonmyObj=newPerson();    myObj.setName("John");//Setthevalueofthenamevariableto"John"    System.out.println(myObj.getName());  } } //Outputs"John" TryitYourself» WhyEncapsulation? Bettercontrolofclassattributesandmethods Classattributescanbemaderead-only(ifyouonlyusethegetmethod),orwrite-only(ifyouonlyusethesetmethod) Flexible:theprogrammercanchangeonepartofthecodewithoutaffectingotherparts Increasedsecurityofdata ❮Previous Next❯ NEW WejustlaunchedW3Schoolsvideos Explorenow COLORPICKER Getcertifiedbycompletingacoursetoday! w3schoolsCERTIFIED.2022 Getstarted CODEGAME PlayGame