Java Program to Pass ArrayList as the function argument

In this example, we will learn to pass an arraylist as the funcion argument in Java.

To understand this example, you should have the knowledge of the following Java programming topics:


Example 1: Pass ArrayList as Function Parameter

import java.util.ArrayList;

class Main {

  public static void display(ArrayList<String> languages) {

    System.out.print("ArrayList: ");
    for(String language : languages) {
      System.out.print(language + ", ");
    }
  }
  public static void main(String[] args) {

    // create an arraylist
    ArrayList<String> languages = new ArrayList<>();
    languages.add("Java");
    languages.add("Python");
    languages.add("JavaScript");

    // passing arraylist as function parameter
    display(languages);
  }
}

Output

ArrayList: Java, Python, JavaScript,

In the above example, we have created an arraylist named languages. Here, we have a method display(). It prints elements of arraylist.

Notice the line,

display(languages);

Here, we have passed languages as the function parameter.


Example 2: Pass ArrayList as Function Parameter by converting into Array

import java.util.ArrayList;

class Main {

  public static void percentage(Integer[] marks) {
    int totalMarks = 300;
    int obtainedMarks = 0;
    for(int mark : marks) {
      obtainedMarks += mark;
    }

    // compute average
    double percent = (obtainedMarks * 100) / totalMarks;
    System.out.println("Percentage: " + percent);
  }
  public static void main(String[] args) {

    // create an arraylist
    ArrayList<Integer> marks = new ArrayList<>();
    marks.add(67);
    marks.add(87);
    marks.add(56);
    System.out.println("Marks: " + marks);

    // passing arraylist as function parameter
    percentage(marks.toArray(new Integer[marks.size()]));
  }
}

Output

Marks: [67, 87, 56]
Percentage: 70.0

In the above example, we have created an arraylist named marks. Notice the line,

percentage(marks.toArray(new Integer[0]));

Here, we are passing the arraylist as an argument to the percentage() method.

Did you find this article helpful?