arturmkrtchyan

|----------------------------------------------------------------------------------------|--------------------|
|                                    Object Header (64 bits)                             |        State       |
|-------------------------------------------------------|--------------------------------|--------------------|
|                  Mark Word (32 bits)                  |      Klass Word (32 bits)      |                    |
|-------------------------------------------------------|--------------------------------|--------------------|
| identity_hashcode:25 | age:4 | biased_lock:1 | lock:2 |      OOP to metadata object    |       Normal       |
|-------------------------------------------------------|--------------------------------|--------------------|
|  thread:23 | epoch:2 | age:4 | biased_lock:1 | lock:2 |      OOP to metadata object    |       Biased       |
|-------------------------------------------------------|--------------------------------|--------------------|
|               

arturmkrtchyan

  private static void enumSwitch();
    Code:
       0: getstatic     #2                  // Field DayOfWeek.FRIDAY:LDayOfWeek;
       3: astore_0      
       4: iconst_0      
       5: istore_1      
       6: getstatic     #3                  // Field Switch$1.$SwitchMap$DayOfWeek:[I
       9: aload_0       
      10: invokevirtual #4                  // Method DayOfWeek.ordinal:()I
      13: iaload        

arturmkrtchyan

import sun.misc.Cleaner;
import sun.misc.Unsafe;
import sun.nio.ch.DirectBuffer;

import java.lang.reflect.Field;
import java.nio.ByteBuffer;

// How to run:
// struct: javac ObjectVsStruct.java && java ObjectVsStruct struct
// object: javac ObjectVsStruct.java && java ObjectVsStruct object

arturmkrtchyan

public class BiasedLocking {

    private static final int LOOP_COUNT = 10000000; // 10 million

    public static void main(final String[] args) {
        incrementCounter();
    }

    public static void incrementCounter() {
        final long startTime = System.currentTimeMillis();

arturmkrtchyan

bash ./configure 
make all

arturmkrtchyan

public boolean isPrime(final int number) {  
    return number > 1 &&  
                IntStream.rangeClosed(2, (int) Math.sqrt(number))  
                        .noneMatch(index -> number % index == 0);
}

arturmkrtchyan

public class AssemblyMain {
 
    public static void main(String[] args) {
        int number = 100000;
        System.out.println("Calculating SUM of the squares of 1 to " + number);
 
        long sum = sum(number);
 
        System.out.println("SUM: " + sum);
    }