Author Archives: Stanislav_Panteleev

Both synchronized and ReentrantLock are used for mutual exclusion in Java (i.e., only one thread can execute a critical section at a time), but they have key differences in capabilities, flexibility, and usage style.

🧹🧵 When Should You Call threadLocal.remove()? ✅ 1. When you’re done with the thread-local value If your thread is long-lived (like in a thread pool), you must clean up the thread-local variable after you’re done using it.

🧵🔐 What is a ThreadLocal Variable? A ThreadLocal is a special Java class that provides thread-local storage. 📌 Each thread that accesses a ThreadLocal variable gets its own independent copy of the variable. So even though many threads use the … Continue reading →

🧵🛠️ How to Dump Threads in Java ✅ 1. Using Command-Line Tools 🔸 A) jstack — Most Common Dumps all thread stack traces of a running JVM.

🔍 In the Java Virtual Machine (JVM), you can control the size of each thread’s stack using the following startup parameter:

✅ Ways to Share Data Between Threads in Java Let’s go step by step from simple to advanced.

🧠 Stack vs Heap in Multithreading Feature Stack Heap 📌 Scope Thread-local (private per thread) Shared among all threads 🧵 Thread-safety ✅ Safe — each thread has its own stack ❌ Not safe — needs synchronization 🧠 Use Stores local … Continue reading →

Java has a modern async feature very similar to Promises in TypeScript, and it’s called CompletableFuture — it lets you run tasks asynchronously without blocking the main thread and chain actions just like promises.

🔁 Callable vs Runnable Feature Runnable Callable<V> Returns result? ❌ No ✅ Yes (generic type V) Can throw exception? ❌ No (must handle inside) ✅ Yes (throws Exception) Method to override run() call()

Let’s compare submit() and execute() clearly — both are used to hand over tasks to a thread pool, but they behave differently in a few key areas. ✅ 1. Return Type Method Returns execute() void submit() Future<?> submit() gives you … Continue reading →