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Hi,<br />
<br />
&nbsp; &nbsp; &nbsp; I am new to java (basically I am a C#.Net guy). I extracted the java.util.Comparator interface. There I can see two abstract methods (1) public abstract int compare(java.lang.Object arg0, java.lang.Object arg1); and (2) public abstract boolean equals(java.lang.Object arg0);. I implemented this interface in MyClass and it is working fine.<br />
<br />
My Question is:<br />
*************<br />
<br />
&nbsp; &nbsp; &nbsp; By normal OOPs rule, we should define all the abstract methods which are available in interface at the time of implementation.<br />
&nbsp; &nbsp; &nbsp; &nbsp;But here we have 2 abstract methods (compare and equals) and I am implementing only campare method. I just ignored the equals methods. But I am not getting any compilation or run-time error.<br />
&nbsp; &nbsp; &nbsp; &nbsp;At the same time, if I not implement the method compare, I am getting compilation error.<br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp;What is the difference between the abstract methods compare and equals? Why &quot;compare&quot; method only mandatory? Please explain to me
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Hi,

      I am new to java (basically I am a C#.Net guy). I extracted the java.util.Comparator interface. There I can see two abstract methods (1) public abstract int compare(java.lang.Object arg0, java.lang.Object arg1); and (2) public abstract boolean equals(java.lang.Object arg0);. I implemented this interface in MyClass and it is working fine.

My Question is:
*************

      By normal OOPs rule, we should define all the abstract methods which are available in interface at the time of implementation.
       But here we have 2 abstract methods (compare and equals) and I am implementing only campare method. I just ignored the equals methods. But I am not getting any compilation or run-time error.
       At the same time, if I not implement the method compare, I am getting compilation error.

       What is the difference between the abstract methods compare and equals? Why "compare" method only mandatory? Please explain to me

interface java.util.Comparator

Java is a platform-independent, object-oriented programming language and run-time environment, designed to have as few implementation dependencies as possible such that developers can write one set of code across all platforms using libraries. Most devices will not run Java natively, and require a run-time component to be installed in order to execute a Java program.