[JAVA] Array vs ArrayList vs HashMap Extended for Statement Race

correction

The comparison operator was wrong (fixed)

What was used

・ Java9 ・ Eclipse

Motivation

I wonder which one is the fastest if I set aside what is best and turn it with an extended for statement.

result

ForEaerVs.java

public class ForEaerVs {
	public static void main(String[] argS) {

		Integer mm;
		
		//Array
		Integer[] arry = new Integer[1000000000];

		for (Integer i = 0 ; i < 1000000000; i++) {
			Integer arryInt = i;
			arry[i] = arryInt;
		}
		long staetTimeArry = System.nanoTime();
			for(Integer iA : arry) {
				mm = iA;
			}
		long endTimeArry = System.nanoTime();
		System.out.println("Array speed:" + (endTimeArry -staetTimeArry));

		// List
		List<Integer> list = new ArrayList<Integer>();
		for (Integer j = 0 ; j < 1000000000; j++) {
			Integer arryInt = j;
			list.add(arryInt);
		}
		long staetTimeList = System.nanoTime();
			for (Integer iL: list) {
				mm = iL;
			}
		long endTimeList = System.nanoTime();
		System.out.println("List speed:" + (endTimeList -staetTimeList));

		
		// HushMap
		HashMap<Integer,Integer> hash = new HashMap<Integer,Integer>();
		for (Integer k = 0 ; k < 1000000000; k++) {
			Integer arryInt = k;
			hash.put(k, arryInt);
		}
		long staetTimeHash = System.nanoTime();
			for (Integer iH : hash.values()) {
				mm = iH;
			}
		long endTimeHash = System.nanoTime();
		System.out.println("Hash speed:" + (endTimeHash -staetTimeHash));

	}
}

ForEaerVsResult.java

Array speed: 4020600
List speed: 11350400
Hash speed: 18974400

The result including the creation time is as follows

ForEaerVsPlusCreateResult.java

Array speed: 35613700
List speed: 98473300
Hash speed: 121742700

Impressions

Although each has different uses, is the array so slow? </ s> Worship the awesomeness of the array seniors

Array speed: 4001200
List speed: 9521900
Hash speed: 19611200
Linked speed: 15211300

Array speed: 32542100
List speed: 80343600
Hash speed: 101256200
Linked speed: 140576800