8/13/2019 Java String Concatenation Benchmark

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String

ConcatenationPerformanceBenchmark

CONTENTS INCLUDE:. String Concatenation Operation. Performance Comparison. Summary. Source Code

Java String

Java String is the most used immutablString operations are using create-ne

String str = hello;str = str.toUppercase();

This snippet of code does not modifywith all the characters of str is changvariable refers to it.

String Concatenation

String concatenation operation can b Concatenation operation + StringBuffer.append() StringBuilder.append()

Concatenation operation + to JavConcatenation operation using StrinSystem.arraycopy() - the new string

StringBuilder is compatible API with

Charts below are the performance cstring in a loop. This benchmark is dX-axis is the number of loops; Y-axis

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STRING CONCATENATION OPER

PERFORMANCE COMPARISON

String Concatenati

le class in Java. Immutable means cant be changw and throw-old strategy.

value of object that variable str refers to. Instead to upper case. The old hello string will be ga

e achieved using,to strings

Strings is done by creating new string and the oBuffer.append and StringBuilder.append is doneo an array of chars containing the old string.

tringBuffer but with no guarantee of synchroniza

omparison of mentioned concatenation operation one using Java 6 Hotspot with JIT enabled.

is the average elapsed time per operation.

Number of loops

TION

REFERENCE CARDon Benchmark

By Leonar Tambunan

d or mutated. All of the Java

, a new String object is createdrbage collected since no more

ld string thrown away.by appends - using native code

tion.

above by appending abcde

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Performance Comparison continued

1. For small number of iterationdoesnt really significant desiterations, StringBuffer & Stri

2. There is no significant differeStringBuffer.

3. The champion of string conca

ABOUT THE AUTHOR

Leonar Tambunan is a software engiLeonard.tambunan@gmail.com

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SUMMARY

Reference Card

s (

8/13/2019 Java String Concatenation Benchmark

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