link管理
链接快照平台
- 输入网页链接，自动生成快照
- 标签化管理网页链接
相关文章推荐
|
听话的煎饼 · iOS safari 后退 js ...· 3 月前 · |
|
|
酒量小的四季豆 · Git push from inside ...· 4 月前 · |
|
|
博学的乌冬面 · Http请求 | uView - ...· 5 月前 · |
|
|
强健的豆浆 · 张德芳：烽火中的居延汉简_中国作家网· 7 月前 · |
|
|
小胡子的蛋挞 · 国产数据库公司达梦登陆科创板 上市首日暴涨177%· 9 月前 · |
link管理
›
Collectors groupingBy() method in Java with Examples - GeeksforGeeks
| python history django geeks |
| https://www.geeksforgeeks.org/collectors-groupingby-method-in-java-with-examples/ |
|
谈吐大方的甘蔗
1 年前 |
-
Courses
- DSA to Development
- For Working Professionals
- For Students
- For School Students
- All Courses
-
Tutorials
-
Data Structures & Algorithms
- DSA for Beginners
- Data Structures
-
Algorithms
- Analysis of Algorithms
- Searching Algorithms
- Sorting Algorithms
- Greedy Algorithms
- Dynamic Programming
- Graph Algorithms
- Pattern Searching
- Recursion
- Backtracking
- Divide and Conquer
- Mathematical Algorithms
- Geometric Algorithms
- Bitwise Algorithms
- Randomized Algorithms
- Branch and Bound
- Algorithms Tutorial
- Complete DSA Tutorial
- Competitive Programming
- Company Wise SDE Sheets
- DSA Cheat Sheets
-
Top Interview Questions
- Top 100 DSA Interview Questions Topic-wise
- Top 50 Array Problems
- Top 50 String Problems
- Top 50 Stack Problems
- Top 50 Heap Problems
- Top 50 Linked List Problems
- Top 50 Tree Problems
- Top 50 Graph Problems
- Top 50 Problems on Recursion Algorithms
- Top 20 Interview Questions on Greedy Algorithms
- Top 20 Interview Questions on Dynamic Programming
- Top 50 Problems on Dynamic Programming (DP)
- Top 20 Interview Questions on Hashing
- Interview Questions on Top 10 Algorithms
- Commonly Asked Data Structure Interview Questions
- DSA Blogs
- Puzzles
-
ML & Data Science
- Learn Python
- Machine Learning
- Data Science using Python
- Data Science using R
- Data Science Packages
-
Data Visualization
- Data Visualization with Python
- Data Visualization with R
- Data Visualization Tools
- Data Analysis
- Deep Learning
- NLP Tutorial
- OpenCV Tutorial
- Interview Questions
- ML Frameworks
-
System Design
-
System Design Tutorial
- What is System Design
- Key Terminologies in System Design
- Analysis and Architecture of Systems
- Scalability in System Design
- Databases in System Design
- High Level Design or HLD
- Low Level Design or LLD
- Communication Protocols
- Web Servers and Proxies
- Case Studies in Designing Systems
- Complete System Design Tutorial
- Software Design Patterns
- System Design Roadmap
- Top 10 System Design Interview Questions and Answers
-
System Design Tutorial
- Interview Corner
- Languages
-
Web Development
- HTML
-
CSS
- CSS Tutorial
- Free CSS Course
- CSS Cheat Sheet
- CSS Preprocessors
- JavaScript
- ReactJS
- Node.js
- PHP
-
AngularJS
- AngularJS Tutorial
- AngularJS Cheat Sheet
- AngularJS Frameworks
-
jQuery
- jQuery Tutorial
- jQuery Cheat Sheet
- jQuery Frameworks
- TypeScript
- JSON
- CSS Frameworks & Libraries
- JS Other Frameworks & Libraries
-
Web Development In Python
- Django
- Flask
- Frontend Projects
- Postman
- Github
- CS Subjects
- DevOps
-
Commerce
- Business Studies
- Accountancy
- Microeconomics
- Statistics for Economics
- Macroeconomics
- Indian Economic Development
- Human Resource Management (HRM)
- Management
- Income Tax
- Finance
- Commerce Complete Guide
-
School Learning
- English Grammar
- School Programming
- Mathematics
- CBSE Syllabus
- Maths Notes (Class 8-12)
- Maths Formulas (Class 8 -11)
- Math Calculators
- NCERT Solutions
- RD Sharma Solutions
- Science Notes
- Physics Notes (Class 8-12)
- Chemistry Notes (Class 8-12)
- Biology Notes (Class 8-12)
- Social Science Syllabus
-
Social Science Notes
- SS Notes (Class 7-12)
- CBSE History Notes (Class 7-10)
- CBSE Geography Notes (Class 7-10)
- CBSE Civics Notes (Class 7-10)
- CBSE Previous Year Papers
- GATE
-
Banking Exams Study Material
- RRB Clerk 2023 Exam
- SBI Clerk
- SBI PO
- IBPS PO
- IBPS Clerk
- UPSC Study Material
- SSC CGL Study Material
- SEO-Search Engine Optimization
- Student
-
Data Structures & Algorithms
- Jobs
- Practice
- Contests
- Explore Our Geeks Community
- Collectors collectingAndThen() method in Java with Examples
- Java 8 | Collectors averagingInt() with Examples
- Java | Collectors maxBy(Comparator comparator) with Examples
- Java Stream | Collectors toCollection() in Java
- Java 8 | Collectors counting() with Examples
- Java | Collectors minBy(Comparator comparator) with Examples
- Java | Collectors averagingLong (ToLongFunction mapper) with Examples
- Collectors toSet() in Java with Examples
- Java | Collectors averagingDouble() with Examples
- Collectors partitioningBy() method in Java
- Java 8 Streams | Collectors.joining() method with Examples
- Collectors toList() method in Java with Examples
- Collectors toMap() method in Java with Examples
- GregorianCalendar getTimeZone() Method in Java
- Number.shortValue() method in java with examples
- GregorianCalendar clone() Method in Java
- Boolean parseBoolean() method in Java with examples
- Boolean booleanValue() method in Java with examples
- GregorianCalendar getGregorianChange() Method
- Explore Our Geeks Community
- Collectors collectingAndThen() method in Java with Examples
- Java 8 | Collectors averagingInt() with Examples
- Java | Collectors maxBy(Comparator comparator) with Examples
- Java Stream | Collectors toCollection() in Java
- Java 8 | Collectors counting() with Examples
- Java | Collectors minBy(Comparator comparator) with Examples
- Java | Collectors averagingLong (ToLongFunction mapper) with Examples
- Collectors toSet() in Java with Examples
- Java | Collectors averagingDouble() with Examples
- Collectors partitioningBy() method in Java
- Java 8 Streams | Collectors.joining() method with Examples
- Collectors toList() method in Java with Examples
- Collectors toMap() method in Java with Examples
- GregorianCalendar getTimeZone() Method in Java
- Number.shortValue() method in java with examples
- GregorianCalendar clone() Method in Java
- Boolean parseBoolean() method in Java with examples
- Boolean booleanValue() method in Java with examples
- GregorianCalendar getGregorianChange() Method
-
T-
It is the type of the input elements.
- K- It is the type the input elements to be converted.
-
Function-
It is the property which is to be applied to the input elements.
- Classifier- It is used to map input elements into the destination map.
- Company
- About Us
- Legal
- Careers
- In Media
- Contact Us
- Advertise with us
- GFG Corporate Solution
- Placement Training Program
- Apply for Mentor
- Explore
- Job-A-Thon Hiring Challenge
- Hack-A-Thon
- GfG Weekly Contest
- Offline Classes (Delhi/NCR)
- DSA in JAVA/C++
- Master System Design
- Master CP
- GeeksforGeeks Videos
- DSA
- Data Structures
- Algorithms
- DSA for Beginners
- Basic DSA Problems
- DSA Roadmap
- Top 100 DSA Interview Problems
- DSA Roadmap by Sandeep Jain
- All Cheat Sheets
- Computer Science
- GATE CS Notes
- Operating Systems
- Computer Network
- Database Management System
- Software Engineering
- Digital Logic Design
- Engineering Maths
- Python
- Python Programming Examples
- Django Tutorial
- Python Projects
- Python Tkinter
- OpenCV Python Tutorial
- Python Interview Question
- Competitive Programming
- Top DS or Algo for CP
- Top 50 Tree
- Top 50 Graph
- Top 50 Array
- Top 50 String
- Top 50 DP
- Top 15 Websites for CP
- School Subjects
- Mathematics
- Physics
- Chemistry
- Biology
- Social Science
- English Grammar
- Commerce
- Accountancy
- Business Studies
- Indian Economics
- Macroeconomics
- Microeconimics
- Statistics for Economics
- Management & Finance
- Management
- HR Managament
- Income Tax
- Finance
- Economics
- Colleges
- Indian Colleges Admission & Campus Experiences
- Top Engineering Colleges
- Top BCA Colleges
- Top MBA Colleges
- Top Architecture College
- Choose College For Graduation
- Companies
- IT Companies
- Software Development Companies
- Artificial Intelligence(AI) Companies
- CyberSecurity Companies
- Service Based Companies
- Product Based Companies
- PSUs for CS Engineers
- Preparation Corner
- Company Wise Preparation
- Preparation for SDE
- Experienced Interviews
- Internship Interviews
- Competitive Programming
- Aptitude Preparation
- Puzzles
- More Tutorials
- Software Development
- Software Testing
- Product Management
- SAP
- SEO
- Linux
- Excel
The
groupingBy()
method of Collectors class in Java are used for grouping objects by some property and storing results in a Map instance. In order to use it, we always need to specify a property by which the grouping would be performed. This method provides similar functionality to SQL’s GROUP BY clause.
Syntax:
public static Collector<T, ?, Map<K, List>> groupingBy(Function classifier)
Type Parameter: This method takes two type parameters:
Parameters: This method accepts two mandatory parameters:
Return value:
It returns a collector as a map.
Below is the program implementation of groupingBy() method:
Program 1:
import
java.util.*;
import
java.util.function.Function;
import
java.util.stream.Collectors;
public
class
GFG {
public
static
void
main(String[] args)
// Get the List
List<String> g
= Arrays.asList(
"geeks"
,
"for"
,
"geeks"
);
// Collect the list as map
// by groupingBy() method
Map<String, Long> result
= g.stream().collect(
Collectors.groupingBy(
Function.identity(),
Collectors.counting()));
// Print the result
System.out.println(result);
{geeks=2, for=1}
Whether you're preparing for your first job interview or aiming to upskill in this ever-evolving tech landscape,
GeeksforGeeks Courses
are your key to success. We provide top-quality content at affordable prices, all geared towards accelerating your growth in a time-bound manner. Join the millions we've already empowered, and we're here to do the same for you. Don't miss out -
check it out now!
Last Updated : 29 Jul, 2021 Like Article
Please go through our recently updated
Improvement Guidelines
before submitting any improvements.
This article is being improved by another user right now.
You can suggest the changes for now and it will be under the article's discussion tab.
You will be notified via email once the article is available for improvement.
Thank you for your valuable feedback!
Please go through our recently updated
Improvement Guidelines
before submitting any improvements.
Suggest Changes
Help us improve. Share your suggestions to enhance the article. Contribute your expertise and make a difference in the GeeksforGeeks portal.