Java: Trim the capacity of an array list the current list size

Last update on March 12 2025 13:33:08 (UTC/GMT +8 hours)

Write a Java program for trimming the capacity of an array list.

Pictorial Presentation:

Sample Solution:-

Java Code:

import java.util.ArrayList;
import java.util.Collections;
  public class Exercise19 {
  public static void main(String[] args) {
          ArrayList<String> c1= new ArrayList<String>();
          c1.add("Red");
          c1.add("Green");
          c1.add("Black");
          c1.add("White");
          c1.add("Pink");
          System.out.println("Original array list: " + c1);
          System.out.println("Let trim to size the above array: ");
          c1.trimToSize();
          System.out.println(c1);
   }
}

Sample Output:

Original array list: [Red, Green, Black, White, Pink]                  
Let trim to size the above array:                                      
[Red, Green, Black, White, Pink] 

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to trim the capacity of an ArrayList using trimToSize() and then print the internal array size if accessible.
• Write a Java program to create an ArrayList with a large capacity, add elements, and then trim it to the current size.
• Write a Java program to compare the performance before and after calling trimToSize() on an ArrayList.
• Write a Java program to simulate dynamic array behavior by manually adjusting the capacity of an ArrayList.

Java Code Editor:

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