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Java

Posted by Matthew Francis
Matthew Francis
6,967 Points

Newbie - Why is "this" not used here? 

public boolean applyGuess(char letter) {
    letter = validateGuess(letter);
    // Why is it not this.letter? I thought this is used to distinguished between variable names and it's values?*/
}

public void setName(String name) {
    this.name = name ;
    // Here, this is used to distinguish between the variable name and the value.*/
}
john larson
john larson
16,594 Points

I don't have an answer, but I'm following your question cause I'm interested in how it compares to JavaScript

Matthew Francis
Matthew Francis
6,967 Points

Same here! I came from javascript and I'm just wondering how "this" interacts in java!

1 Answer

Simon Coates
Simon Coates
28,695 Points
Simon Coates
Simon Coates
28,695 Points

you can use 'this' if the variable you want to access is on the object, but not for local variables/parameters. the 'name' variable is on the object - having a scope (duration/accessibility) throughout the object. Hence 'this' can be used to differentiate it from a local variable with the same name. eg this.name = name ; The letter variable and the second name variable (the parameter) exist only within the methods that use them - not on the object itself. (unless there are multiple variables with the same name in your current scope, the 'this' keyword is optional - eg, if the parameter was rename newName, then the assignment line could be just name = newName )

'this' is used to differentiate between different types of variable (instance vs param/local). see https://docs.oracle.com/javase/tutorial/java/nutsandbolts/variables.html and https://docs.oracle.com/javase/tutorial/java/javaOO/thiskey.html