Wanted to understand how compareTo method works when there is no implmentation
Could you please help me understand how the below code works
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
I could see that there is no implementation given for the compareTo method and it still works fine, could you please let me know how it works.
I wanted to understand how the natural ordering is done. where can i see the code for that.
compareto
asked Nov 13 '18 at 11:07
VigneshVignesh
165
add a comment |
Could you please help me understand how the below code works
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
I could see that there is no implementation given for the compareTo method and it still works fine, could you please let me know how it works.
I wanted to understand how the natural ordering is done. where can i see the code for that.
compareto
asked Nov 13 '18 at 11:07
VigneshVignesh
165
add a comment |
Could you please help me understand how the below code works
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
I could see that there is no implementation given for the compareTo method and it still works fine, could you please let me know how it works.
I wanted to understand how the natural ordering is done. where can i see the code for that.
compareto
asked Nov 13 '18 at 11:07
VigneshVignesh
165
Could you please help me understand how the below code works
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
I could see that there is no implementation given for the compareTo method and it still works fine, could you please let me know how it works.
I wanted to understand how the natural ordering is done. where can i see the code for that.
compareto
compareto
asked Nov 13 '18 at 11:07
VigneshVignesh
165
asked Nov 13 '18 at 11:07
VigneshVignesh
165
asked Nov 13 '18 at 11:07
VigneshVignesh
165
asked Nov 13 '18 at 11:07
VigneshVignesh
165
asked Nov 13 '18 at 11:07
VigneshVignesh
165
165
add a comment |
add a comment |
1 Answer
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The method has defined a constraint on the type T. Any T will be extending the Comparable interface which contains the compareTo() method.
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
Based on that contract, any object passed into this method as v and w has to implement the compareTo() method.
To verify that, you can try something like below where a compilation error is shown.
public static void main(String args)
less(new Object(), new Object());
Hope this helps you in understanding it better.
answered Jan 9 at 6:19
lkamallkamal
2,0371121
add a comment |
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1 Answer
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active
oldest
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The method has defined a constraint on the type T. Any T will be extending the Comparable interface which contains the compareTo() method.
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
Based on that contract, any object passed into this method as v and w has to implement the compareTo() method.
To verify that, you can try something like below where a compilation error is shown.
public static void main(String args)
less(new Object(), new Object());
Hope this helps you in understanding it better.
answered Jan 9 at 6:19
lkamallkamal
2,0371121
add a comment |
The method has defined a constraint on the type T. Any T will be extending the Comparable interface which contains the compareTo() method.
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
Based on that contract, any object passed into this method as v and w has to implement the compareTo() method.
To verify that, you can try something like below where a compilation error is shown.
public static void main(String args)
less(new Object(), new Object());
Hope this helps you in understanding it better.
answered Jan 9 at 6:19
lkamallkamal
2,0371121
add a comment |
The method has defined a constraint on the type T. Any T will be extending the Comparable interface which contains the compareTo() method.
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
Based on that contract, any object passed into this method as v and w has to implement the compareTo() method.
To verify that, you can try something like below where a compilation error is shown.
public static void main(String args)
less(new Object(), new Object());
Hope this helps you in understanding it better.
answered Jan 9 at 6:19
lkamallkamal
2,0371121
The method has defined a constraint on the type T. Any T will be extending the Comparable interface which contains the compareTo() method.
static <T extends Comparable<T>> boolean less(T v, T w)
return v.compareTo(w) < 0;
Based on that contract, any object passed into this method as v and w has to implement the compareTo() method.
To verify that, you can try something like below where a compilation error is shown.
public static void main(String args)
less(new Object(), new Object());
Hope this helps you in understanding it better.
answered Jan 9 at 6:19
lkamallkamal
2,0371121
answered Jan 9 at 6:19
lkamallkamal
2,0371121
answered Jan 9 at 6:19
lkamallkamal
2,0371121
answered Jan 9 at 6:19
lkamallkamal
2,0371121
2,0371121
add a comment |
add a comment |
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