Why Java provided two different interfaces(Comparable/Comparator) to compare objects? [duplicate]

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• When should a class be Comparable and/or Comparator? [closed] 11 answers

Why Java provides two different interfaces(Comparable/Comparator) to compare objects . Better It can go with only one. Right? I mean instead of proving a new interface(Comparator) to compare objects with multiple attribute, Java can simply extended "Comparable" interface to achieve the "Comparator" interface logic. Am I correct? . Please let me know , is there any specific reason for this.