Discover and read the best of Twitter Threads about #Java
Most recents (24)
Learning #Java is a never-ending story for me: I just learned about " double-brace initialization", which creates an anonymous class derived from the specified class (the outer braces), and provides an initialiser block within that class (the inner braces). e.g. 👇
For example, this code:
List<Integer> l = new ArrayList<>();
l.add(1);
l.add(2);
May look like:
new ArrayList<Integer>() {{
add(1);
add(2);
}};
List<Integer> l = new ArrayList<>();
l.add(1);
l.add(2);
May look like:
new ArrayList<Integer>() {{
add(1);
add(2);
}};
Or it may look like constructor with named parameters:
public class User {
String name;
String surname;
String email;
}
User user = new User() {{
name = "John";
surname = "Doe";
}};
public class User {
String name;
String surname;
String email;
}
User user = new User() {{
name = "John";
surname = "Doe";
}};
#Java performance comparison.
Today I decided to check the performance of different ways of converting an int variable to a String object in Java. 🧵👇
Today I decided to check the performance of different ways of converting an int variable to a String object in Java. 🧵👇
I searched on Stackoverflow:
📍Integer.toString(i)
📍"" +i
📍String.valueOf(i)
📍new StringBuilder().append(i).toString() - a bit strange way, but it was one of the suggestions😄
I have implemented 4 benchmarks using the JMH framework (see pictures).
Results 👇
📍Integer.toString(i)
📍"" +i
📍String.valueOf(i)
📍new StringBuilder().append(i).toString() - a bit strange way, but it was one of the suggestions😄
I have implemented 4 benchmarks using the JMH framework (see pictures).
Results 👇
✅Integer.toString(i) - 43.424 29.721 ns/op
✅"" +i - 27.870 ns/op
✅String.valueOf(i) - 28.371 ns/op
❌new StringBuilder().append(i).toString() - ns/op
Just don't use StringBuilder approach. Other approaches are for your taste. but I personally prefer: String.valurOf(i).
✅"" +i - 27.870 ns/op
✅String.valueOf(i) - 28.371 ns/op
❌new StringBuilder().append(i).toString() - ns/op
Just don't use StringBuilder approach. Other approaches are for your taste. but I personally prefer: String.valurOf(i).
⚠️#Java performance comparison⚠️
I decided to compare the performance of different collection iteration options. In particular:
📍 for loop
📍enhanced for loop
📍for loop with an Iterator
📍stream
Details🧵👇
I decided to compare the performance of different collection iteration options. In particular:
📍 for loop
📍enhanced for loop
📍for loop with an Iterator
📍stream
Details🧵👇
To test it, I have implemented 4 Benchmark methods, each iterating through list of positive integers and checking them for equality to -1. And at the end of the method, it returns 0 since non was found. In short: Just iterating through the entire collection. 
Results:
✅for (Integer i : list) 781 ns/op
✅for (int i = 0; i < listSize; i++) 785 ns/op
✅while (iterator.hasNext()) 788 ns/op
❌list.stream() ns/op 3256 ns/op 4x slower 😱👀
✅for (Integer i : list) 781 ns/op
✅for (int i = 0; i < listSize; i++) 785 ns/op
✅while (iterator.hasNext()) 788 ns/op
❌list.stream() ns/op 3256 ns/op 4x slower 😱👀
⚠️#Java performance tip⚠️
Use primitive types instead of wrappers.
Java primitive types:
📍byte
📍short
📍int
📍long
📍float
📍double
📍char
📍boolean
More details and explanation in 🧵👇
Use primitive types instead of wrappers.
Java primitive types:
📍byte
📍short
📍int
📍long
📍float
📍double
📍char
📍boolean
More details and explanation in 🧵👇
To show the difference in performance between primitive and wrapper objects I have created a benchmark which just creates an array of "int" and "Integer" and fills them with an index. Sizes of array: "10", "100", "1000", "10000"
Results: 👇
Results: 👇
Array of size 10:
❌ arrayOfWrappers 26.131 ns/op - 2.7x slower
✅ arrayOfPrimitives 9.462 ns/op
❌ arrayOfWrappers 26.131 ns/op - 2.7x slower
✅ arrayOfPrimitives 9.462 ns/op
#ApacheKafka has integrations with most of the languages used these days.
@alexsotob covers its integration with #Java and discusses how to provision, configure & secure an Apache Kafka cluster on a #Kubernetes cluster: bit.ly/3HN0Tqw
#InfoQ
Series Contents 👇
@alexsotob covers its integration with #Java and discusses how to provision, configure & secure an Apache Kafka cluster on a #Kubernetes cluster: bit.ly/3HN0Tqw
#InfoQ
Series Contents 👇
2/6 ➡️ Apache Kafka is a stream-processing platform for storing, consuming, and processing data streams in real-time. Learn how to produce and consume data using Kafka and Quarkus: bit.ly/3HGby6x
#ApacheKafka #Quarkus #Java
#ApacheKafka #Quarkus #Java
3/6 ➡️ The Kafka Streams project consumes real-time streams of events as they are produced, apply transformations, join streams, etc. Learn how to use Kafka Streams and Quarkus: bit.ly/3RGUbqy
#KafkaStreams #Quarkus #Java
#KafkaStreams #Quarkus #Java
10 articles to Guarantee success to you in 2023!
Open thread🔗(open tweet):
#Web3 #SmartContracts #serverless #Backend #cryptocurrency #fintech #Gamedev $ETH $BTC #Bitcoin #java #javascript #html #python #rustlang #firebase #ios #MySQL #startup #agile #php #AI #data #CSS #NodeJS
Open thread🔗(open tweet):
#Web3 #SmartContracts #serverless #Backend #cryptocurrency #fintech #Gamedev $ETH $BTC #Bitcoin #java #javascript #html #python #rustlang #firebase #ios #MySQL #startup #agile #php #AI #data #CSS #NodeJS
#programming with a fellow #dev can be more productive than you can envision!
medium.com/p/528d555f7846
medium.com/p/528d555f7846
⚠️#Java performance tip⚠️
Don't use "+" for string concatenation. Use StringBuilder or StringBuffer instead.
I have created a benchmark to compare the speed of StringBuilder, StringBuffer and "+" concatenation for 2, 3, 5, 10, 50, and 100 strings.
Details in 🧵👇
Don't use "+" for string concatenation. Use StringBuilder or StringBuffer instead.
I have created a benchmark to compare the speed of StringBuilder, StringBuffer and "+" concatenation for 2, 3, 5, 10, 50, and 100 strings.
Details in 🧵👇
The scenario is simple:
s/sb = ""/new StringBuffer/Builder();
for (int i = 0; i < size; i++) {
s+=i;/sb.append(i);
}
return sb.toString();
size = 2, 3, 5, 10, 50, and 100
Size hundred produced super strange result, which I can't explain yet. 😕
s/sb = ""/new StringBuffer/Builder();
for (int i = 0; i < size; i++) {
s+=i;/sb.append(i);
}
return sb.toString();
size = 2, 3, 5, 10, 50, and 100
Size hundred produced super strange result, which I can't explain yet. 😕
Concat 2 strings:
❎ s+= i; 25.528 ns/op ~15% slower
✅ stringBuilder.append(i); 21.265 ns/op
✅ stringBuffer.append(i); 21.251 ns/op
The difference is slight, so it is up to you to decide what to use. However, if you want the lowest latency, go with StringBuilder.
❎ s+= i; 25.528 ns/op ~15% slower
✅ stringBuilder.append(i); 21.265 ns/op
✅ stringBuffer.append(i); 21.251 ns/op
The difference is slight, so it is up to you to decide what to use. However, if you want the lowest latency, go with StringBuilder.
#Java performance Tip: `parallelStream()` is way slower than regular `stream()` on small amount of data. I have created a simple benchmark and run it on my 8-CPU laptop. The difference is 160x for some cases. 😲
Details 🧵 👇
Details 🧵 👇
👷The setup is to run the same code for streams of 10, 1000, 10_000, 100_000, and 1000_000 items long in standard and parallel modes:
list.stream()
.filter(i -> i == -1)
.findAny()
.orElse(0);
list.stream()
.filter(i -> i == -1)
.findAny()
.orElse(0);
10 items stream:
✅stream()
❌parallelStream() 161x SLOWER ‼️
✅stream()
❌parallelStream() 161x SLOWER ‼️
#Java performance Tip: When need to copy items from one array to anoyther one, don't use loops. Use the more efficient Arrays.copyOf or System.arraycopy method instead.
Performance test details in 🧵👇
Performance test details in 🧵👇
Given:
☕ int[] arr = {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, 26, 27, 28, 29, 30};
❌ int[] arr2 = new int[30];
for (int i = 0; i < arr.length; i++) {
arr2[i] = arr[i];
}
☕ int[] arr = {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, 26, 27, 28, 29, 30};
❌ int[] arr2 = new int[30];
for (int i = 0; i < arr.length; i++) {
arr2[i] = arr[i];
}
✅ int[] arr2 = new int[30];
System.arraycopy(arr, 0, arr2, 0, arr.length);
~25% faster ⚡
System.arraycopy(arr, 0, arr2, 0, arr.length);
~25% faster ⚡
Cuando eres #programador #junior, una de las cosas más difíciles a superar de un proceso de selección son las #pruebastecnicas 💻En este HILO 🧵te voy a dejar 5⃣ recursos GRATIS 🔝🔝 para que puedas superar las pruebas técnicas de nivel junior con más facilidad ⬇️⬇️⬇️ #it
En este vídeo de @powerhdeleon de 2⃣0⃣ minutos tienes 5⃣ de las pruebas técnicas más comunes planteadas para #programadores #junior resueltas 🔥🔥 #informatica #software #it
En este vídeo de 1⃣5⃣ minutos del gran @MoureDev tienes 6⃣ pruebas técnicas de las más comunes planteadas para #programadores #junior resueltas 🔥🔥 #informatica #software #it
Libro
Un vídeo algo antiguo pero efectivo para empezar con POO.
Un vídeo algo antiguo pero efectivo para empezar con POO.
Ecuación 2 grado
Un vídeo mas completo que el anterior.
Un vídeo mas completo que el anterior.
1. The unclear licensing model has been the most significant barrier to GraalVM adoption for years. However, at @JavaOne 2022, it was announced that @Oracle will make the GraalVM CE a part of the OpenJDK. Project Galahad has been set up to carry out the process - ❤️ that name.
2. @Google announced that it was joining the @adoptium working group as a Strategic Member. Google didn't just limit itself to throwing piles of 💰 at JDK, but together with @AlibabaGroup began working on Java Class Pre-Initialization to accelerate the cold start of applications.
cool was my job 10 years ago.
#nosql? we used the largest transactional database on planet: @objectivitydb CAP: #ACID or #BASE ? BOTH!
#Java? #Microservices, SaaS, PaaS, for German and European EDIfact, FTAM, ATLAS,#NCTS, #AES,... Toll/ Duane before #RodJohnson, #GavinKing...
#nosql? we used the largest transactional database on planet: @objectivitydb CAP: #ACID or #BASE ? BOTH!
#Java? #Microservices, SaaS, PaaS, for German and European EDIfact, FTAM, ATLAS,#NCTS, #AES,... Toll/ Duane before #RodJohnson, #GavinKing...
... invented @springframework and #ORM and #EricEvans #DDD ... new names for the same Things?
No! #DevOps are more than just #SysAdmins who develop with a script language hopefully #python and
No! #DevOps are more than just #SysAdmins who develop with a script language hopefully #python and
... and #PlatformEngineers are more than magic PowerPoint2Java Compiler or SoftwareDevs who are Application Managers for a handfull hours per week or the 2nd Level Firepissung Support Unit.
Here are 3 programs training 100 ppl to become a Software Engineers, Quality Assurance Testers & Data Analysts in the next 14-16 weeks. + offering roles paying avg salaries upwards of $100K+ 🧵
Shipt is giving 20, $13K Scholarships for a Software Engineering bootcamp!🎉hackbrightacademy.com/shipt/
🎉Mentors
➡ US citizens/Perm
💻Remote
📆Apply by Jan 23, Starts Feb 27
🐍Gain #SoftwareEngineering skills in 14 weeks
💰Job Interviews
#womenwhocode #blacktechtwitter #codenewbie
🎉Mentors
➡ US citizens/Perm
💻Remote
📆Apply by Jan 23, Starts Feb 27
🐍Gain #SoftwareEngineering skills in 14 weeks
💰Job Interviews
#womenwhocode #blacktechtwitter #codenewbie
Perficient is giving 40+, $13K Scholarships for Software Engineering, Quality Assurance & Data Analyst bootcamps!🎉hackbrightacademy.com/perficient/
🎉Mentors
➡ US citizens/Perm resident
💻Remote
📆Apply by Feb 27, Starts Apr 3
💰Job Interview
#womenwhocode #blacktechtwitter #codenewbie
🎉Mentors
➡ US citizens/Perm resident
💻Remote
📆Apply by Feb 27, Starts Apr 3
💰Job Interview
#womenwhocode #blacktechtwitter #codenewbie
Summary of #Java 8,9,10,11,12,13,14,15,16,17,18,19 features.
All features in a single tweet. #retweet #share #like #follow #bookmark Good know.
Thread 👇
All features in a single tweet. #retweet #share #like #follow #bookmark Good know.
Thread 👇
#Java 19 Features:
- Record Patterns
- Linux/RISC-V Port
- Foreign Function & Memory API
- Virtual Threads
- Vector API (Fourth Incubator)
- Pattern Matching for the switch
- Structured Concurrency (Incubator)
- Record Patterns
- Linux/RISC-V Port
- Foreign Function & Memory API
- Virtual Threads
- Vector API (Fourth Incubator)
- Pattern Matching for the switch
- Structured Concurrency (Incubator)
#Java 18 Features:
- UTF-8 by Default
- Simple Web Server
- Code Snippets in Java API Doc
- Reimplement Core Reflection with Method Handles
- Vector API
- Internet-Address Resolution SPI
- Foreign Function & Memory API
- Pattern Matching for switch
- UTF-8 by Default
- Simple Web Server
- Code Snippets in Java API Doc
- Reimplement Core Reflection with Method Handles
- Vector API
- Internet-Address Resolution SPI
- Foreign Function & Memory API
- Pattern Matching for switch
What is Java 8 lambdas and functional programming?
A thread 🧵👇
A thread 🧵👇
Java 8 introduced a number of new features to the language, including lambda expressions, which enable functional programming in Java. But what exactly are lambda expressions and how do they work?
A lambda expression is a short block of code that can be passed around as an argument or returned as a value. It's essentially a function without a name that can be used wherever a function interface is expected.
🧵 Everyone’s chatting about 🤖#ChatGPT. Here are 11 things it can do for #malware analysts, #security researchers, and #reverse engineers. A thread >>👇 🧵
1/13
1/13
🙋🏻♀️ Learn how to use reverse engineering tools more effectively. Use #openAI chat bot to get rapid interactive help on your reversing tools.
2/13
2/13
We moved our projects from #Java 11 to #Java 17 almost right after the LTS release. Here is a list of the Top 5 features that I have used and enjoyed for more than a year that may convince you to upgrade your projects. 🧵👇
`
record Point(int x, int y) {}
`
- this all you need to create POJO. No, constructors, getters, setters, etc. Just removed verbosity, which was disliked and criticized by many community members. 📓
record Point(int x, int y) {}
`
- this all you need to create POJO. No, constructors, getters, setters, etc. Just removed verbosity, which was disliked and criticized by many community members. 📓
Text blocks:
`String text = """
Long
formated
text.
""";
`
My SQL queries and JSON blocks in tests don't look like graveyards with all those `+.` ➕❌
`String text = """
Long
formated
text.
""";
`
My SQL queries and JSON blocks in tests don't look like graveyards with all those `+.` ➕❌
QuPath v0.4.0 is now available!
Download it at qupath.github.io
#opensource #bioimageanalysis #digitalpathology #java #javafx
Download it at qupath.github.io
#opensource #bioimageanalysis #digitalpathology #java #javafx
There are so many new things that it'll take some days to describe even just the main ones.
For now, I'll start by mentioning a few of the user interface improvements.
QuPath v0.4.0 is more welcoming than previous versions... and a bit more stylish.
For now, I'll start by mentioning a few of the user interface improvements.
QuPath v0.4.0 is more welcoming than previous versions... and a bit more stylish.
In fact, you can even style it in your own unique way if you really want to, thanks to #javafx & css (ideally in a nicer way than in my screenshots).
qupath.readthedocs.io/en/0.4/docs/re…
qupath.readthedocs.io/en/0.4/docs/re…
Top 6 #Java testing libraries every Java developer should know about and use 👇
AssertJ by @JoCosti - fluent chaining assertions java library. One of the most powerful and convenient ways to write assertions. It's also included in the @springboot test framework.
assertj.github.io/doc/
assertj.github.io/doc/
👨💻 Data Analysis Roadmap with FREE resources 💸
#BigData #Analytics #DataScience #AI #MachineLearning #IoT #PyTorch #Python #RStats #TensorFlow #Java #JavaScript #ReactJS #React #Serverless #DataScientist #Programming #100DaysofCode #DevOps #SQL #CyberSecurity #Flutter #PHP
#BigData #Analytics #DataScience #AI #MachineLearning #IoT #PyTorch #Python #RStats #TensorFlow #Java #JavaScript #ReactJS #React #Serverless #DataScientist #Programming #100DaysofCode #DevOps #SQL #CyberSecurity #Flutter #PHP
1. Math and Statistics
Intro to Statistics - Udacity
🌐 bit.ly/3GMZe5n
Statistics - Udacity
🌐 bit.ly/3VKKzfB
Statistical Learning - Stanford University
🌐 bit.ly/3VqA5Sj
Intro to Statistics - Udacity
🌐 bit.ly/3GMZe5n
Statistics - Udacity
🌐 bit.ly/3VKKzfB
Statistical Learning - Stanford University
🌐 bit.ly/3VqA5Sj
2. Excel
Introduction to MS Excel - Simplilearn
🌐 bit.ly/3u1h1OJ
Microsoft Excel: Online Tutorial for Beginners - Chandoo
🌐 bit.ly/3XzUHJO
Microsoft Excel Tutorial for Beginners - Free Code Camp
🌐 bit.ly/3Vax74G
Introduction to MS Excel - Simplilearn
🌐 bit.ly/3u1h1OJ
Microsoft Excel: Online Tutorial for Beginners - Chandoo
🌐 bit.ly/3XzUHJO
Microsoft Excel Tutorial for Beginners - Free Code Camp
🌐 bit.ly/3Vax74G
Vamos con una selección de #ofertas laborales para developers, de la mano de nuestra plataforma de empleo @JobRun_Dev.
¿Será alguno el trabajo de vuestros sueños? 👀
¿Será alguno el trabajo de vuestros sueños? 👀
📲 Desarrollador #Android 📲
· Empresa: @Hiberus.
· Rango salarial: 22.000€ - 60.000€.
· Modalidad: Remoto.
jobrun.dev/empresas/hiber…
· Empresa: @Hiberus.
· Rango salarial: 22.000€ - 60.000€.
· Modalidad: Remoto.
jobrun.dev/empresas/hiber…
🍏 Desarrollador #iOS 🍏
· Empresa: @Hiberus.
· Rango salarial: 22.000€ - 60.000€.
· Modalidad: Remoto.
jobrun.dev/empresas/hiber…
· Empresa: @Hiberus.
· Rango salarial: 22.000€ - 60.000€.
· Modalidad: Remoto.
jobrun.dev/empresas/hiber…
ROADMAP para ser BACKEND Developer
¿Queréis un roadmap con RECURSOS GRATUITOS para ser un gran desarrollador BACKEND?
Os dejo 7 recursos totalmente GRATIS para aprender las BASES que cualquier desarrollador BACKEND debe conocer
🧵👇
#backend #code #coding #programming #coding
¿Queréis un roadmap con RECURSOS GRATUITOS para ser un gran desarrollador BACKEND?
Os dejo 7 recursos totalmente GRATIS para aprender las BASES que cualquier desarrollador BACKEND debe conocer
🧵👇
#backend #code #coding #programming #coding
1️⃣Aprende las BASES DE INTERNET
Antes de empezar a programar, entiende qué es Internet, qué es el protocolo HTTP y cómo funciona un navegador
Aquí tenéis un artículo muy interesante
vox.com/2014/6/16/1807…
Antes de empezar a programar, entiende qué es Internet, qué es el protocolo HTTP y cómo funciona un navegador
Aquí tenéis un artículo muy interesante
vox.com/2014/6/16/1807…
2️⃣Frontend básico (HTML y CSS)
⚠️Opcional pero RECOMENDABLE⚠️
Aunque quieras ser desarrollador backend, es importante que conozcas las bases del frontend, es decir: #HTML y #CSS
Tienes el curso de @freeCodeCamp para aprender HTML, CSS y Responsive Web
freecodecamp.org/learn/2022/res…
⚠️Opcional pero RECOMENDABLE⚠️
Aunque quieras ser desarrollador backend, es importante que conozcas las bases del frontend, es decir: #HTML y #CSS
Tienes el curso de @freeCodeCamp para aprender HTML, CSS y Responsive Web
freecodecamp.org/learn/2022/res…
