Somebody explain me method chaining.

Hi.
I'm looking for somebody to give me an explanation of how does Method Chaining (I think this is how it's called) work.
i.e:
myObject.setPrice(2)
.setQuantity(10)
.solveLifeProblems()
.setAvailavility(true);
Where's the theory about this?
Can I do this with every class?
What requisites are needed so that I can use this technique with my classes?
What if the method, say solveLifeProblems() returns somethin strange (such as an boolean or another object)?
Thanks.

All you're doing is invoking a method on the return value of another method. All solveLiveProblems() has to do is return a class with a method called setAvailability.
Sodog()
.cat()
.monkey();is the same as
dog().cat().monkey();which is the same as (for example)
Hammer hammer = dog();
Screwdriver sd = hammer.cat();
sd.monkey();I'd advise not formatting your code like this until you have more experience.

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im new to java and xml.Been reading a lot regarding
java and don't seem to have a problem with it...Okay.
the problem is the xml part...im doing a simple GUI
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Please check the following code out......
Snippet 1) compiles while Snippet 2) does not. Can someone explain. Thanks in advance for your help.
Snippet 1)
public class AQuestion
public void method(Object o)
System.out.println("Object Verion");
public void method(String s)
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Snippet 2)
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foo( SuperClass parm ) {}
foo( SubClass parm ) {}
Now somewhere in your code you do this:
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foo( myVar );Which one do you want the JVM to call? Well, you want
it to call the more specific one.
So it calls foo( SubClass ). But if you sayNo, it doesnt. At compile time the compiler cannot know the complete type of myVar. It can only assure that myVar is of the type SuperClass. And it inserts no dynamic type-checking. And therefore it calls foo(SuperClass).
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foo(SuperClass) is called !!!
foo(null);
foo(SubClass) is called.
SuperClass myVar = new SubClass();
foo( myVar );
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yes.
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I think this has nothin to do with type casts.

Somebody explain me method chaining.

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