in which scenario, we should use static method in VF page contoller?

Hello Saloni,

#Static Method :

Static methods are methods that act globally and not in the context of a particular object of a class. Being global, static methods only have access to its provided inputs and other static (global) variables.

This example illustrates static vs. non-static methods
public class LightJedi {
public void slashLightsaber() {
// Vooooom!
}

public static String getJediCode() {
String code = 'There is no emotion, there is peace.';
code += 'There is no ignorance, there is knowledge.';
code += 'There is no passion, there is serenity.';
code += 'There is no death, there is the Force.';
return code;
}

public static String describeRank(String rank) {
String description;
if (rank == 'Initiate') {
description = 'Jedi hopeful';
} else if (rank == 'Padawan') {
description = 'Apprentice of a Jedi Knight';
} else if (rank == 'Knight') {
description = 'Completed the Jedi Trials';
} else if (rank == 'Master') {
description = 'David Liu';
}
return description;
}
}

// Elsewhere...
LightJedi davidLiu = new LightJedi();

// Non-static methods require an object for context
davidLiu.slashLightsaber();

// Static methods aren't related to a particular object
LightJedi.getJediCode();

// You don't even use an object to call a static method!
System.debug(LightJedi.describeRank('Master')); // David Liu

Other examples of static methods could be convert millimeters to centimeters, subtract two numbers, and convert String to uppercase.