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The compareTo and compare Methods

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The Comparable<T> interface requires one method: 

public interface Comparable<T> {

    public int compareTo(T other);

}

And the Comparator<T> interface requires one method: 

public interface Comparator<T> {

    public int compare(T t1, T t2);

}

These two methods do essentially the same thing, with one minor difference: compareTo compares this to other, whereas compare compares t1 to t2, not caring at all about this.

Aside from that difference, the two methods have similar requirements. Specifically (for compareTo), Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. Thus, for the comparison of a and b:

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Comparable and Comparator:
* Comparable and Comparator
* Sorting a List using ComparableT or a ComparatorT
* The compareTo and compare Methods
* Natural comparable vs explicit comparator sorting
* Creating a Comparator using comparing method
* Sorting Map entries
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0 Inheritance
1 Getting started with Java
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182 C++ Comparison
183 CompletableFuture
184 Contributors