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How to Write Method Headers


written by

milo chang

published on august 5, 2020

Last updated on August 4, 2020

Look at this chunk of code: 💻

public class Cats {    public int countNumFeet (int numCats)    {         return 4*numCats;    } ​    // There may be instance variables, constructors, and other methods not    // shown. }

Can you identify the method header? 🤔

That's right! 👏 It's "public int countNumFeet (int numCats)"! 🐱

Breaking it Down: 🔍

The keyword "public" means that this method can be accessed from other classes.

  • It can be replaced by the word "private" to give you:

private int countNumFeet (int numCats)

  • Putting "private" means that the method can only be accessed within the "Cats" class

The keyword "int" tells you what this method returns when it is called.

  • In this case, it returns an integer value after it is called
  • It can be replaced by "double", "boolean", "String", or the name of a class if the method returns an object
  • If the word "void" is there instead of the other options, this means the method doesn't return anything

The word "countNumFeet" is the name of the method.

  • This can be replaced with anything without changing what the method does
  • It's best if you make the name of the method something that lets people easily know what it's doing

The "int numCats" tells you what is being passed into this method.

  • In the example, an integer called "numCats" is being passed in
  • You can have a method that has nothing being passed in:

public int countNumFeet ()
  • You can also have a method that has multiple parameters passed in:
public int countNumFeet (int numCats, int numEars, boolean isAngry)

Method headings may also include the phrases "static" or "abstract", but this will be discussed in later articles.  ​

Try it out! 😃

#1) Write the header for a method that can only be accessed within the class it's declared in. This method takes in a String called "text" and doesn't return anything. Call your method "example1".  (Scroll down for the answer)

#2) Write the header for a method that can be accessed from other classes. This method takes nothing in and returns a boolean. Call your method "example2". (Scroll down for the answer)

#3) Write the header for a method that can be accessed from other classes. This method takes in a boolean "testPassed" and an integer "score". It returns a String. Call your method "example3". (Scroll down for the answer)

Answers: ✔

#1) private void example1 (String text)#2) public boolean example2 ()#3) public String example3 (boolean testPassed, int score)

Summary: 🎉✨

You can write a method header with just a few simple steps.

  1. Choose public or private 
  2. Choose what the method returns: void (nothing), intdoublebooleanString, or the name of a class
  3. Choose the name of the method
  4. Choose what parameters to pass into the method

That's it! You're ready to start writing your own method headers! 👏

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