How to Reduce the Size of the Stream with the Limit Method in Java 8

See Java: Tips and Tricks for similar articles.

The limit method of the Stream class introduced in Java 8 allows the developer to limit the number of elements that will be extracted from a stream. The limit method is useful in those applications where the user wishes to process only the initial elements that occur in the stream. To learn how to reduce the size of the stream with the limit method, follow these five steps.

  1. Open your text editor and create the Java program that will create the stream and apply the limit method. Type in the following Java statements:
    import java.util.stream.*;
    import java.util.*;
    import java.io.*;
    public class ReduceStreamSizeWithlimitMethod {
    private static List names=new ArrayList<>();
    static {
    	names.add("Stephen");
    	names.add("Regina");
    	names.add("Edward");
    	names.add("Miguel");
    	names.add("George");
    	names.add("Brad");
    }
    public static void main (String args[]) {
    	Console console=System.console();
    	int userLimit=Integer.parseInt(console.readLine("Please enter the number of persons you wish to display: "));
    	// if the user enters a number greater than the list size then set number equal to size
    	if (userLimit > names.size()) {
    		userLimit=names.size();
    	}
    	names.stream().limit(userLimit).forEach(System.out::println);
    }
    }
    The stream will be created from the ArrayList that is defined on line 4. Note that a static block is used to add elements to the ArrayList. A static block is executed one time when the program is loaded into memory. The user is asked how many persons are to be displayed on the console. The result entered by the user is checked to see if it is greater than the number of elements in the ArrayList. If this is the case, then the result is equated to the number of elements in the list. The ArrayList is then converted to a stream and the limit method is applied using the number entered by the user. I have highlighted the limit method in the image below:Java Source for Limit Method
  2. Save your file as ReduceStreamSizeWithlimitMethod.java.
  3. Open a command prompt and navigate to the directory containing your new Java program. Then type in the command to compile the source and hit Enter.Compile Program with Limit Method
  4. You are ready to test your Java program. Type in the command to run the Java runtime launcher and hit Enter. When prompted for the limit, type "3" as shown below. The output displays the first three names because the limit method was applied to the stream using the number you entered.Run Program with Limit Method
  5. Test your program again using a limit greater than the size of the ArrayList, which is 6. Type in the command to run the Java runtime launcher and hit Enter. When prompted for the limit, type "7" as shown below. The output now displays all of the names because the limit method was applied to the stream using the size of the ArrayList as the limit number.Run Program with Limit Method

Related Articles

  1. How to Check Object Type in Java
  2. How to Create a Jar File in Java
  3. How to Compile Packages in Java
  4. How to Throw an Exception in Java
  5. How to Create an Exception Class in Java
  6. How to Use the super Keyword to Call a Base Class Constructor in Java
  7. How to Use the Comparator.comparing Method in Java 8
  8. How to Use System.in in Java
  9. How to Call an Interface Method in Java
  10. How to Add a Time Zone in the Java 8 Date/Time API
  11. How to Rethrow an Exception in Java
  12. How to Use the instanceof Operator with a Generic Class in Java
  13. How to Instantiate an Object in Java
  14. How to Filter Distinct Elements from a Collection in Java 8
  15. How to Create a Derived Class in Java
  16. How to Skip Elements with the Skip Method in Java 8
  17. How to Create a Java Bean
  18. How to Implement an Interface in Java
  19. How to Compare Two Objects with the equals Method in Java
  20. How to Set PATH from JAVA_HOME
  21. How to Prevent Race Conditions in Java 8
  22. How to Write a Block of Code in Java
  23. How to Display the Contents of a Directory in Java
  24. How to Group and Partition Collectors in Java 8
  25. How to Create a Reference to an Object in Java
  26. How to Reduce the Size of the Stream with the Limit Method in Java 8 (this article)
  27. How to Write an Arithmetic Expression in Java
  28. How to Format Date and Time in the Java 8 Date/Time API
  29. How to Use Comparable and Comparator in Java
  30. How to Break a Loop in Java
  31. How to Use the this Keyword to Call Another Constructor in Java
  32. How to Write a Unit Test in Java
  33. How to Declare Variables in Java
  34. How to Override Base Class Methods with Derived Class Methods in Java
  35. How to Use Serialized Objects in Java
  36. How to Write Comments in Java
  37. How to Implement Functional Interfaces in Java 8
  38. How to Write Type Parameters with Multiple Bounds in Java
  39. How to Add Type and Repeating Annotations to Code in Java 8
  40. How to Use Basic Generics Syntax in Java
  41. How to Map Elements Using the Map Method in Java 8
  42. How to Work with Properties in Java
  43. How to Write while and do while Loops in Java
  44. How to Use the finally Block in Java
  45. How to Write for-each Loops in Java
  46. How to Create a Method in Java
  47. How to Continue a Loop in Java
  48. How to Handle Java Files with Streams
  49. How to Create an Interface Definition in Java
  50. How Default Base Class Constructors Are Used with Inheritance