Some useful Java examples
JDK 5/6 Language features
- A static nested class is 'Static Nested Class'. A non static nested class becomes 'Inner Class'
- How shift operation based calculation is faster than mathematical equivalent
- Simulator for 'OutOfMemoryError'
- Singleton using 'enum'
- How Remote Method Invocation(RMI) works
JDK 7 language features
- Usage of 'MethodHandles'
- Diamond operator(<>)
- Remove compiler warning about generics variable arguments invocation using '@SafeVarargs' annotation
JDK 8 language features
- Performance comparison between MethodHandle, Reflection, LambdaMetafactory and Direct method call
- Interface with 'default' method
- Interface with 'static' method
- Class with 'default' method
- Functional interfaces
- Runnable is a functional interface now (java.lang.FunctionalInterface)
- Predicate as functional interfaces
- Using 'Collections.sort' on Lambdas
- Using 'List.forEach' on Lambdas
- List Streaming example
JDK 9 language features
- How 'jshell' (Read-Eval-Print Loop : JEP-222) works
- How 'VarHandle' class (JEP-193) works
- Factory methods for Collections (JEP 269)
- Underscore ('_') identifier is removed
- Example of Flow API(JEP 266 : Reactive streams)
- Interface with 'private' method
JVM features
- How JVM method-inline optimization works
- Another example of JVM method-inline optimization
- Failed Hoisting example
- Successful Hoisting example
- Another successful Hoisting example
- How JVM finds the HotSpot and converts them into native instruction using JIT compiler
- Object size at runtime
- Primitive value size at runtime
- Unsafe objects using 'sun.misc.Unsafe' (Heap bypassing)
- Example of System.identityHashCode
Util classes
Concurrency
- Usage of 'CountDownLatch'
- Usage of 'CyclicBarrier'
- Usage of 'Exchanger'
- Usage of 'Semaphore'
- Usage of 'Timer' and 'TimerTask'
- Example of failed concurrency
- Example of successful concurrency
- Example of Java Monitor Pattern
- Example to find number of cores of a processor
- Example of blocking array implemented using 'ReentrantLock'
- Example of fork and join pool class 'ForkJoinPool'
Data structures & algorithms
- Stack
- Reverse a word using a stack
- Queue
- Circular Queue
- Linked Queue
- Priority Queue
- Linear Search
- Binary Search
- Bubble Sort
- Insertion Sort
- Selection Sort
- Binary Tree
- Armstrong Number
- Floyds Triangle
- Example on Hex Numbers
- Example on Prime Numbers
- Example on Random Numbers
- How to test a number is odd by using '%'
- Check if a string is anagram
- Check if a string contains DuplicateChars
- Get frequency of words in a string
- Get repeating and non repeating chars from a string
- Find the Levenshtein distance between two strings
Spark
- Program to count 'words per statement'
- Example of various spark functions
- Program to count 'words per statement', arrived on network socket
- Program to count 'products per country'