Constructor Overloading in Java

Java Programming Language Class, Object and Methods in java (Article) Class, Object and Methods in java (Program)

1203

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Program:

<span class="com">// Constructor Overloading</span><span class="pln">
	
 </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">StudentClass</span><span class="pun">{</span><span class="pln">
    </span><span class="kwd">int</span><span class="pln"> rollno</span><span class="pun">;</span><span class="pln">
    </span><span class="typ">String</span><span class="pln"> name</span><span class="pun">;</span><span class="pln">
    </span><span class="kwd">int</span><span class="pln"> age</span><span class="pun">;</span><span class="pln">

    </span><span class="typ">StudentClass</span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> i</span><span class="pun">,</span><span class="typ">String</span><span class="pln"> n</span><span class="pun">){</span><span class="pln">
    rollno </span><span class="pun">=</span><span class="pln"> i</span><span class="pun">;</span><span class="pln">
    name </span><span class="pun">=</span><span class="pln"> n</span><span class="pun">;</span><span class="pln">
    </span><span class="pun">}</span><span class="pln">

    </span><span class="typ">StudentClass</span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> i</span><span class="pun">,</span><span class="typ">String</span><span class="pln"> n</span><span class="pun">,</span><span class="kwd">int</span><span class="pln"> a</span><span class="pun">){</span><span class="pln">
    rollno </span><span class="pun">=</span><span class="pln"> i</span><span class="pun">;</span><span class="pln">
    name </span><span class="pun">=</span><span class="pln"> n</span><span class="pun">;</span><span class="pln">
    age</span><span class="pun">=</span><span class="pln">a</span><span class="pun">;</span><span class="pln">
    </span><span class="pun">}</span><span class="pln">

    </span><span class="kwd">void</span><span class="pln"> display</span><span class="pun">(){</span><span class="pln">
		</span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="pln">rollno</span><span class="pun">+</span><span class="str">" "</span><span class="pun">+</span><span class="pln">name</span><span class="pun">+</span><span class="str">" "</span><span class="pun">+</span><span class="pln">age</span><span class="pun">);</span><span class="pln">
		</span><span class="pun">}</span><span class="pln">

    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">void</span><span class="pln"> main</span><span class="pun">(</span><span class="typ">String</span><span class="pln"> args</span><span class="pun">[]){</span><span class="pln">
    </span><span class="typ">StudentClass</span><span class="pln"> s1 </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">StudentClass</span><span class="pun">(</span><span class="lit">1</span><span class="pun">,</span><span class="str">"Rahim"</span><span class="pun">);</span><span class="pln">
    </span><span class="typ">StudentClass</span><span class="pln"> s2 </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">StudentClass</span><span class="pun">(</span><span class="lit">2</span><span class="pun">,</span><span class="str">"Ram"</span><span class="pun">,</span><span class="lit">25</span><span class="pun">);</span><span class="pln">
    s1</span><span class="pun">.</span><span class="pln">display</span><span class="pun">();</span><span class="pln">
    s2</span><span class="pun">.</span><span class="pln">display</span><span class="pun">();</span><span class="pln">
   </span><span class="pun">}</span><span class="pln">
</span><span class="pun">}</span><span class="pln">

</span><span class="com">/*

Constructor overloading is a technique in Java in which a class can have any
number of constructors that differ in parameter lists.The compiler
differentiates these constructors by taking into account the number of
parameters in the list and their type.

*/</span>

Output:

1 Rahim 0
2 Ram 25
Press any key to continue . . .

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