Why is this method showing an error in the if clause?

Question

I am writing a void method that needs to change the value of stocklevel in my object part0. However, there shows an error when i try to write the logic.

AssembledStockLevel

public int calculateAvailForAssembly(){
    if(basica.getStockLevel() <= basicb.getStockLevel()){
        assembledstocklevel = basica.getStockLevel();
    } else { assembledstocklevel = basicb.getStockLevel();
    }
    return assembledstocklevel;
}

Code showing error

   public void changeStockLevel(){
    if(assembledstocklevel <= basica.getStockLevel()){
   [Error is here -->]basica.getStockLevel() = basica.getStockLevel() - assembledstocklevel;
    }
}

The error says left-hand side of an assignment must be a variable??

basica is a variable i made to refer to part0 object

just updated. empty variable that get assigned in calculateAvailForAssembly() method — danielb, Oct 16 '15 at 06:17
Because it's invalid syntax. Your left-hand side is a method invocation, not a variable. — Jeroen Vannevel, Oct 16 '15 at 06:17
Same code base question from you few hours ago [Trouble with setter method and returning getter](http://stackoverflow.com/questions/33161946/trouble-with-setter-method-and-returning-getter). — YoungHobbit, Oct 16 '15 at 06:20
it's not the same. that question was based on trying to get the assembledstocklevel. This one is changing the stocklevel of part objects not the assembledstocklevel — danielb, Oct 16 '15 at 06:34

score 2 · Answer 1 · answered Oct 16 '15 at 06:17

2

basica.getStockLevel() returns a reference to a value. You can't assign anything to that reference. You should have a setter method for stock level and use it to update its value.

Something like:

basica.setStockLevel(basica.getStockLevel() - assembledstocklevel)

answered Oct 16 '15 at 06:17

Pablo Francisco Pérez Hidalgo

27,044
8
36
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i've put that in, but realised I don't think I want the method void? There is no change to basica (part0) stocklevel. This is oh so confusing lol – danielb Oct 16 '15 at 06:25
@danielb I lost you there :( – Pablo Francisco Pérez Hidalgo Oct 16 '15 at 06:30

score 2 · Answer 2 · answered Oct 16 '15 at 06:18

2

You're using a reference to set a value, use a setter method.

basica.setStockLevel(basica.getStockLevel() - assembledstocklevel);

answered Oct 16 '15 at 06:18

James S

308
1
7

score 1 · Answer 3 · answered Oct 16 '15 at 06:20

1

You cant assign anything to a method. You have set through a setter method like :

basica.setStockLevel(basica.getStockLevel() - assembledstocklevel)

answered Oct 16 '15 at 06:20

Rahman

3,755
3
26
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Why is this method showing an error in the if clause?

3 Answers3