{"id":3216,"date":"2020-01-23T13:45:57","date_gmt":"2020-01-23T08:15:57","guid":{"rendered":"https:\/\/cns72.com\/vytcdc.com.sg\/?p=3216"},"modified":"2020-01-23T13:45:57","modified_gmt":"2020-01-23T08:15:57","slug":"polymorphism-in-java","status":"publish","type":"post","link":"https:\/\/cns72.com\/vytcdc.com.sg\/polymorphism-in-java\/","title":{"rendered":"Polymorphism in Java"},"content":{"rendered":"

The word polymorphism means having many forms. In simple words,<\/span><\/p>\n

Real life example of polymorphism:<\/span><\/b>\u00a0A person at the same time can have different characteristic. Like a man at the same time is a father, a husband, an employee. So the same person possess different behavior in different situations. This is called polymorphism.<\/span><\/p>\n

Example<\/span><\/p>\n

public<\/span> class<\/span> Animal<\/span>{<\/span><\/p>\n

\u00a0\u00a0 <\/span>…<\/span><\/p>\n

\u00a0\u00a0 <\/span><\/span>public<\/span> void<\/span> sound(){<\/span><\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span>System<\/span>.<\/span>out<\/span>.println(<\/span>“Animal is making a sound”<\/span>);\u00a0\u00a0 <\/span><\/span><\/p>\n

\u00a0\u00a0 <\/span>}<\/span><\/p>\n

}<\/span><\/p>\n

Now let\u2019s say we two subclasses of Animal class<\/span>:\u00a0Horse<\/span><\/code>\u00a0and\u00a0Cat<\/span><\/code><\/span>\u00a0that extends (<\/span>like\u00a0<\/span>Inheritance<\/span><\/a>)\u00a0<\/span>Animal<\/span><\/code>\u00a0<\/span>class. We can provide the implementation to the same method like this:<\/span><\/p>\n

public<\/span><\/span> class<\/span><\/span> Horse<\/span><\/span> extends<\/span><\/span> Animal<\/span><\/span>{<\/span><\/span><\/pre>\n
...<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>@Override<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>public<\/span><\/span> void<\/span><\/span> sound<\/span><\/span>(){<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>System<\/span><\/span>.<\/span><\/span>out<\/span><\/span>.<\/span><\/span>println<\/span><\/span>(<\/span><\/span>\"Neigh\"<\/span><\/span>);<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
}\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span><\/pre>\n
and<\/span><\/p>\n
public<\/span><\/span> class<\/span><\/span> Cat<\/span><\/span> extends<\/span><\/span> Animal<\/span><\/span>{<\/span><\/span><\/pre>\n
...<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>@Override<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>public<\/span><\/span> void<\/span><\/span> sound<\/span><\/span>(){<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>System<\/span><\/span>.<\/span><\/span>out<\/span><\/span>.<\/span><\/span>println<\/span><\/span>(<\/span><\/span>\"Meow\"<\/span><\/span>);<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
}<\/span><\/span><\/pre>\n
We had the common action for all subclasses\u00a0<\/span>sound() Because of Animal class we get
\nsound() method in Horse and Cat, <\/span><\/code>This is a perfect example of polymorphism, see the difference horse Neigh and cat Meow, each Animal has a different sound<\/span><\/p>\n
There are two types of polymorphism in java:<\/span><\/strong><\/p>\n
1) Static Polymorphism also known as compile time polymorphism<\/span><\/strong><\/p>\n
2) Dynamic Polymorphism also known as runtime polymorphism<\/span><\/strong><\/p>\n
\"\"Compile time Polymorphism (or Static polymorphism)<\/span><\/b><\/p>\n
Polymorphism that is checked in compile time is known as static polymorphism<\/span><\/p>\n
Method overloading is an example of compile time polymorphism.<\/span><\/p>\n
Method Overloading in Java<\/span><\/b><\/p>\n
If a class has multiple methods having same name but different in parameters, it is known as <\/span>Method Overloading in java<\/span><\/b><\/a>.<\/span><\/p>\n
class<\/span><\/span> SimpleCalculator<\/span><\/span><\/p>\n
{<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>int<\/span><\/span> add<\/span><\/span>(<\/span><\/span>int<\/span><\/span> a<\/span><\/span>,<\/span><\/span> int<\/span><\/span> b<\/span><\/span>)<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>{<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>return<\/span><\/span> a<\/span><\/span>+<\/span><\/span>b<\/span><\/span>;<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>int<\/span><\/span>\u00a0 <\/span>add<\/span><\/span>(<\/span><\/span>int<\/span><\/span> a<\/span><\/span>,<\/span><\/span> int<\/span><\/span> b<\/span><\/span>,<\/span><\/span> int<\/span><\/span> c<\/span><\/span>)<\/span><\/span>\u00a0 <\/span><\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0<\/span><\/span><\/span>{<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>return<\/span><\/span> a<\/span><\/span>+<\/span><\/span>b<\/span><\/span>+<\/span><\/span>c<\/span><\/span>;<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
}<\/span><\/span><\/pre>\n
public<\/span><\/span> class<\/span><\/span> Demo<\/span><\/span><\/pre>\n
{<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>public<\/span><\/span> static<\/span><\/span> void<\/span><\/span> main<\/span><\/span>(<\/span><\/span>String<\/span><\/span> args<\/span><\/span>[])<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>{<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span>\u00a0\u00a0 <\/span><\/span><\/span>SimpleCalculator<\/span><\/span> obj <\/span><\/span>=<\/span><\/span> new<\/span><\/span> SimpleCalculator<\/span><\/span>();<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>System<\/span><\/span>.<\/span><\/span>out<\/span><\/span>.<\/span><\/span>println<\/span><\/span>(<\/span><\/span>obj<\/span><\/span>.<\/span><\/span>add<\/span><\/span>(<\/span><\/span>10<\/span><\/span>,<\/span><\/span> 20<\/span><\/span>));<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>System<\/span><\/span>.<\/span><\/span>out<\/span><\/span>.<\/span><\/span>println<\/span><\/span>(<\/span><\/span>obj<\/span><\/span>.<\/span><\/span>add<\/span><\/span>(<\/span><\/span>10<\/span><\/span>,<\/span><\/span> 20<\/span><\/span>,<\/span><\/span> 30<\/span><\/span>));<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
}<\/span><\/span><\/pre>\n
 <\/b>Results<\/span><\/b><\/p>\n
30<\/span><\/span><\/pre>\n
60<\/span><\/span><\/pre>\n
Runtime Polymorphism (or Dynamic polymorphism)<\/span><\/b>\u00a0<\/span><\/b><\/p>\n
class<\/span><\/span> Employee<\/span><\/span>{<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>public<\/span><\/span> void<\/span><\/span> profile<\/span><\/span>(){<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>System<\/span><\/span>.<\/span><\/span>out<\/span><\/span>.<\/span><\/span>println<\/span><\/span>(<\/span><\/span>\"Employee\"<\/span><\/span>);<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
}<\/span><\/span><\/pre>\n
public<\/span><\/span> class<\/span><\/span> Contract <\/span><\/span>extends<\/span><\/span> Employee<\/span><\/span> {<\/span><\/span><\/pre>\n
\u00a0<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>public<\/span><\/span> void<\/span><\/span> profile<\/span><\/span>(){<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>System<\/span><\/span>.<\/span><\/span>out<\/span><\/span>.<\/span><\/span>println<\/span><\/span>(<\/span><\/span>\"Employee of Contract\"<\/span><\/span>);<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
}<\/span><\/span><\/pre>\n
public<\/span><\/span> class<\/span><\/span> Part_Time <\/span><\/span>extends<\/span><\/span> Employee<\/span><\/span> {<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>public<\/span><\/span> void<\/span><\/span> profile<\/span><\/span>(){<\/span><\/span><\/pre>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/span>System<\/span><\/span>.<\/span><\/span>out<\/span><\/span>.<\/span><\/span>println<\/span><\/span>(<\/span><\/span>\"Employee of Partime\"<\/span><\/span>);<\/span><\/span><\/pre>\n
\u00a0\u00a0 <\/span><\/span><\/span>}<\/span><\/span><\/pre>\n
}<\/span><\/span><\/pre>\n
 <\/b>It is also known as late binding or Dynamic binding.<\/span><\/p>\n
\"\"<\/b><\/p>\n
In the above example while compile time s.draw() point to shape class.<\/span><\/p>\n
 \"\"<\/span><\/b><\/p>\n
In the above example while compile time s.draw() point to shape class. <\/span>Java training courses<\/span><\/b><\/a> <\/b>are clearly educate for java concepts. <\/span><\/b><\/p>\n
 <\/p>\n","protected":false},"excerpt":{"rendered":"
The word polymorphism means having many forms. In simple words, Real life example of polymorphism:\u00a0A person at the same time can have different characteristic. Like a man at the same time is a father, a husband, an employee. So the same person possess different behavior in different situations. This is called polymorphism. Example public class […]<\/p>\n","protected":false},"author":1,"featured_media":3217,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[45],"tags":[],"yoast_head":"\nPolymorphism in Java - TCDC<\/title>\n<link rel=\"canonical\" href=\"https:\/\/cns72.com\/vytcdc.com.sg\/polymorphism-in-java\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Polymorphism in Java - TCDC\" \/>\n<meta property=\"og:description\" content=\"The word polymorphism means having many forms. In simple words, Real life example of polymorphism:\u00a0A person at the same time can have different characteristic. Like a man at the same time is a father, a husband, an employee. So the same person possess different behavior in different situations. This is called polymorphism. 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