JMH benchmark for String replace

ref:

• http://openjdk.java.net/projects/code-tools/jmh
• http://java-performance.info/jmh/
• http://java-performance.info/introduction-jmh-profilers/
• http://hg.openjdk.java.net/code-tools/jmh/file/tip/jmh-samples/src/main/java/org/openjdk/jmh/samples/

#build jar

mvn clean package

#get help from cmd java -jar target/benchmarks.jar -h

• List matching benchmarks -- java -jar target/benchmarks.jar -l
• List profilers -- java -jar target/benchmarks.jar -lprof

#run

java -jar target/benchmarks.jar  StringReplaceBenchmark -wi 3 -i 6 -f 1 -tu ms

Benchmark                                      Mode  Cnt     Score     Error   Units
StringReplaceBenchmark.test4String            thrpt    6  1255.017 ± 230.012  ops/ms
StringReplaceBenchmark.test4StringUtils       thrpt    6  4068.229 ±  67.708  ops/ms
StringReplaceBenchmark.test4fast              thrpt    6  4821.035 ±  97.790  ops/ms
StringReplaceBenchmark.test4lang3StringUtils  thrpt    6  3186.007 ± 102.786  ops/ms

java -jar target/benchmarks.jar  StringReplaceBenchmark -wi 3 -i 6 -f 1  -bm thrpt,avgt -tu us

Benchmark                                      Mode  Cnt  Score   Error   Units
StringReplaceBenchmark.test4String            thrpt    6  1.238 ± 0.210  ops/us
StringReplaceBenchmark.test4StringUtils       thrpt    6  4.076 ± 0.049  ops/us
StringReplaceBenchmark.test4fast              thrpt    6  4.714 ± 0.044  ops/us
StringReplaceBenchmark.test4lang3StringUtils  thrpt    6  3.185 ± 0.042  ops/us
StringReplaceBenchmark.test4String             avgt    6  0.787 ± 0.174   us/op
StringReplaceBenchmark.test4StringUtils        avgt    6  0.250 ± 0.002   us/op
StringReplaceBenchmark.test4fast               avgt    6  0.211 ± 0.002   us/op
StringReplaceBenchmark.test4lang3StringUtils   avgt    6  0.317 ± 0.004   us/op

java -jar target/benchmarks.jar  StringReplaceBenchmark -wi 3 -i 6 -f 1 -prof gc