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Arrays of Objects

 
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Hello,

Why doesn't this flag a compilation error?


Thanks in advance for your help.

 
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Because an array of anything is in itself an Object.
 
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neither would this


It's because an object array is an object.
 
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If I am reading the code correctly, you have an array of objects, o[], containing a single element. That element is an Object array of arrays.
 
Sebastian Janisch
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I hate being only seconds late !! ;-)
 
Campbell Ritchie
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I usually find Rob Prime is a few seconds ahead of me
 
W. Joe Smith
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Must be that delay for the information to cross the pond .

Actually, come to think of it, I don't know if Rob lives across the pond or not....or, for that matter, if JR is hosted across the pond.......
 
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I believe JR is located in the US of A, so both Campbell and me live across the great pond.
 
Anup Om
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Thank You
 
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I live near a tiny pond.
 
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Hi, All.......

It's said that in K&B's book,


When you assign an array to a previously declared array reference, the array you're assigning must be the same dimension as the reference you're assigning it to. ...




Then these line are wrong? .........
 
Campbell Ritchie
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The bit about two-d is wrong. There is no such thing as a 2-D array in Java. Look at the Java™ Tutorials, where it says it's an array of arrays.
A reference must be declared and assigned the same type. An int[] is different from an int[][], but both count as objects. And an int isn't an object. You can assign squeegees[0] to blots (or vice versa) because they are both the same type, viz int[]. Both are however null in the code you quoted.
 
Abimaran Kugathasan
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have a look here!
 
Campbell Ritchie
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Abimaran Kugathasan wrote:have a look here!

Thank you. It is useful to quote such links.
 
Abimaran Kugathasan
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Campbell Ritchie wrote:

Abimaran Kugathasan wrote:have a look here!

Thank you. It is useful to quote such links.



You are welcome!
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