Comparison of Arraylist, vector and LinkedList

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Summarize

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First of all, their underlying implementations are different,Arraylist and vectors are based on arrays, and LinkedList is based on linked lists.

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In addition, vector and ArrayList are also based on the implementation of the array, but there are many synchronized methods in vector source code, the description is thread-safe, synchronous, and ArrayList is thread insecure, non-synchronous

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Due to the addition of many synchronized methods, the vector will be slow

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For example, I also add 2,000,000 the same string to the two data structures to compare the time of its insertion

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Millis have passed when using Arraylist.

124 Millis have passed when using vectors.

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Test code

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public class Arraylistandlinkedlistandvector {

private static final String base = "base string.";

private static final int count = 2000000;

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public static void Arraylisttest () {

Long begin, end;

Begin = System.currenttimemillis ();

ArrayList list = new arraylist<> ();

for (int i = 0; i < count; i++) {

List.add ("add");

}

End = System.currenttimemillis ();

System.out.println ((End-begin)

+ "Millis have passed when using Arraylist.");

}

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public static void Linkedlisttest () {

Long begin, end;

Begin = System.currenttimemillis ();

LinkedList list = new linkedlist<> ();

for (int i = 0; i < count; i++) {

List.add ("add");

}

End = System.currenttimemillis ();

System.out.println ((End-begin)

+ "Millis have passed when using LinkedList.");

}

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public static void Vectortest () {

Long begin, end;

Begin = System.currenttimemillis ();

Vector vector = new vector<> ();

StringBuilder test = new StringBuilder (base);

for (int i = 0; i < count; i++) {

Vector.add ("add");

}

End = System.currenttimemillis ();

System.out.println ((End-begin)

+ "Millis have passed when using Vector.");

}

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public static void Main (string[] args) {

Arraylisttest ();

Linkedlisttest ();

Vectortest ();

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}

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Comparison of Arraylist, vector and LinkedList