1. Home
  2. /
  3. Java Typing Test
  4. /
  5. Collection and Stream API

Collection and Stream API - Java Typing CST Test

Skip to main content
CodeSpeedTest
Languages
Start TypingJump into a test — pick any languageAdaptive TrainingUnlock chars as you master themPractice DrillsFocused sessions targeting weak spotsDaily ChallengesNew coding challenges every dayRace ModeCompete against others in real timeAI OpponentRace against an AI at your WPM levelTournamentsLive coding speed tournamentsArcade GamesZType, Overkill Survival, Glyphica & moreGamificationXP, coins, badges & quests
LeaderboardGlobal rankings for every languageCertificatesEarn verifiable Bronze / Silver / Gold certsActivityDaily streaks & historical analyticsProfileYour stats, badges & achievements
Browse Languages500+ languages with real code examplesBlogTips, guides & deep divesFree ToolsWPM calculator, typing speed report & moreFAQCommon questions answeredGetting StartedNew to CodeSpeedTest?AboutOur story & missionSupportGet help — Pro users get priorityContactGet in touch with the team
Pricing
Mode:
Duration:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
import java.util.*;
import java.util.stream.Collectors;

public class StreamExample {
public static void main(String[] args) {
List<String> names = Arrays.asList(
"Alice", "Bob", "Charlie", "David", "Eve"
);

List<String> filteredNames = names.stream()
.filter(name -> name.length() > 3)
.map(String::toUpperCase)
.sorted()
.collect(Collectors.toList());

System.out.println("Filtered names: " + filteredNames);

Optional<String> longest = names.stream()
.max(Comparator.comparing(String::length));

longest.ifPresent(name ->
System.out.println("Longest name: " + name)
);
}
}
Coding works best on desktop or with an external keyboard.
CodeSpeedTest

Improve your coding speed, code accuracy, and programming syntax WPM with practice sessions across 500+ programming languages.

Quick Links

HomeAboutFeaturesGetting StartedLanguages

Legal & Support

Pro ⚡ PricingContactPrivacy PolicyTerms of Service

Connect

CodeSpeedTest on GitHubCodeSpeedTest on TwitterEmail CodeSpeedTest

© 2026 CodeSpeedTest. All rights reserved.

Collection and Stream API — Java Code

Shows modern Java features including streams, lambda expressions, and collection operations.

import java.util.*;
import java.util.stream.Collectors;

public class StreamExample {
	public static void main(String[] args) {
		List<String> names = Arrays.asList(
		"Alice", "Bob", "Charlie", "David", "Eve"
		);

		List<String> filteredNames = names.stream()
		.filter(name -> name.length() > 3)
		.map(String::toUpperCase)
		.sorted()
		.collect(Collectors.toList());

		System.out.println("Filtered names: " + filteredNames);

		Optional<String> longest = names.stream()
		.max(Comparator.comparing(String::length));

		longest.ifPresent(name ->
		System.out.println("Longest name: " + name)
		);
	}
}

Java Language Guide

Java is a robust, object-oriented, platform-independent programming language designed for reliability, performance, and scalability. It powers enterprise systems, Android apps, backend services, banking infrastructure, and large distributed systems used globally.

Primary Use Cases

  • ▸Enterprise backend systems
  • ▸Android application development
  • ▸Financial/banking systems
  • ▸Cloud microservices (Spring Boot, Quarkus)
  • ▸Large distributed systems
  • ▸Big data pipelines (Hadoop, Spark)

Notable Features

  • ▸Platform independence via JVM
  • ▸Garbage collection for memory safety
  • ▸Rich standard library
  • ▸Modern functional features (lambdas, streams)
  • ▸Strong concurrency APIs
  • ▸Huge enterprise ecosystem (Spring)

Origin & Creator

Created by James Gosling at Sun Microsystems (1991-1995). Officially released in 1995. Evolved through major versions: Java 5 (Generics), Java 8 (Lambdas & Streams), Java 9+ (Modules), Java 17+ (LTS), Project Loom (virtual threads), and modern performance optimizations.

Industrial Note

Java dominates banking, fintech, insurance, enterprise ERPs, government software, and high-scale backend services (Netflix, Amazon, LinkedIn). It remains the strongest enterprise language due to JVM performance, stability, concurrency, and massive tooling ecosystem.

Quick Explain

  • ▸Java compiles to JVM bytecode, allowing it to run on any platform with a Java Virtual Machine.
  • ▸It is designed around OOP principles, concurrency, security, and predictable performance.
  • ▸Used in enterprise backend systems, Android apps, cloud microservices, and financial platforms.

Core Features

  • ▸JVM runtime and bytecode execution
  • ▸Object-oriented design
  • ▸Generics and type safety
  • ▸Concurrency with threads/executors
  • ▸Functional APIs with Streams

Learning Path

  • ▸Learn Java basics & OOP
  • ▸Master Collections & Streams
  • ▸Learn Spring Boot
  • ▸Learn Hibernate/JPA
  • ▸Build enterprise projects

Practical Examples

  • ▸Build a REST API with Spring Boot
  • ▸Develop Android applications
  • ▸Create multithreaded systems
  • ▸Build microservices deployed on cloud

Comparisons

  • ▸More stable than JavaScript
  • ▸More enterprise-ready than Python
  • ▸More mature than Kotlin but more verbose
  • ▸Less low-level than Go/Rust

Strengths

  • ▸Extremely reliable and stable
  • ▸Massive enterprise adoption
  • ▸High performance with JVM optimizations
  • ▸Great tooling (IntelliJ, Maven, Gradle)
  • ▸Backwards compatibility across versions

Limitations

  • ▸Verbose syntax compared to modern languages
  • ▸Higher memory consumption
  • ▸Startup time slower than Go/Rust
  • ▸Requires JVM runtime environment

When NOT to Use

  • ▸Ultra low-latency native systems
  • ▸High-performance games requiring engines
  • ▸Small automation scripts (use Python)
  • ▸Memory-constrained microcontrollers

Cheat Sheet

  • ▸Common Java syntax patterns
  • ▸Collections & Stream operators
  • ▸Thread pool utilities
  • ▸Spring annotations

FAQ

  • ▸Is Java still relevant?
  • ▸Yes - it's one of the most used languages in enterprise, finance, Android, and cloud.
  • ▸Is Java good for beginners?
  • ▸Yes - it teaches strong fundamentals in OOP and design.
  • ▸Is Java fast?
  • ▸Very - JIT and JVM optimizations make it high-performance.
  • ▸Why do companies choose Java?
  • ▸Reliability, scalability, security, and huge ecosystem.

30-Day Skill Plan

  • ▸Week 1: OOP + Collections
  • ▸Week 2: Streams + Lambdas
  • ▸Week 3: Spring Boot
  • ▸Week 4: Databases + Microservices

Final Summary

  • ▸Java is a powerful, scalable, enterprise-ready language.
  • ▸Ideal for backend systems, Android apps, microservices, and fintech.
  • ▸Backed by massive tooling and community support.
  • ▸Learning Java provides long-term career stability.

Project Structure

  • ▸src/main/java for code
  • ▸src/test/java for tests
  • ▸pom.xml or build.gradle
  • ▸resources/ for configs and assets
  • ▸target/build/ for compiled output

Monetization

  • ▸Enterprise backend jobs
  • ▸Android app development
  • ▸Java consulting
  • ▸Cloud microservice engineering

Productivity Tips

  • ▸Use IntelliJ shortcuts
  • ▸Use Lombok for boilerplate
  • ▸Use records for data models
  • ▸Automate builds with Gradle

Basic Concepts

  • ▸Data types and variables
  • ▸Classes, objects, and interfaces
  • ▸Inheritance and polymorphism
  • ▸Generics and collections
  • ▸Lambdas and streams
  • ▸Exception handling

Official Docs

  • ▸Java Official Documentation
  • ▸Spring Boot Reference Guide
  • ▸OpenJDK Documentation

More Java Typing Exercises

Java Basic Class and ObjectJava Map and HashMap ExampleJava List Sorting ExampleJava Exception Handling ExampleJava ForEach with LambdaJava Optional ExampleJava Filter and Collect ExampleJava Set ExampleJava Custom Comparator Example

Practice Other Languages

CReactPythonC++RustTypeScriptKotlinPHPC#RubyMqlCqlN1qlCypherGremlin