Kotlin 编程入门与性能测试-优快云博客

参考资料和站点

http://kotlinlang.org/ 官方网站

https://github.com/JetBrains/kotlin/releases/tag/v1.0.6 下载compiler，如果IDEA已经安装了，不需要安装即可直接使用

http://kotlinlang.org/docs/reference/

http://kotlinlang.org/docs/kotlin-docs.pdf 这个参考很全面

http://kotlinlang.org/api/latest/jvm/stdlib/index.html 标准库

http://kotlinlang.org/docs/reference/idioms.html 惯用法

https://github.com/Kotlin/kotlin-koans 例子练习

https://blog.jetbrains.com/kotlin 官方blog

https://blog.jetbrains.com/kotlin/category/releases/ 发布历史

https://github.com/JetBrains/kotlin-examples 例子

https://github.com/JetBrains/kotlin-benchmarks 和JAVA的性能比较

http://www.println.net/ 国内的短视频

Kotlin Benchmarks

https://github.com/JetBrains/kotlin-benchmarks

报告结果拷贝到本机的IIS上，并能够获取Google等Javascript CDN，才可看到报告【这里有个很好的性能测试工具使用参考JMH org.openjdk.jmh】

Comparison with Baseline

For multicolumn search separate subqueries with semicolon: "IntListBenchmark;manual;1000"

Difference is current score minus baseline score. Positive values are regressions, negative are gains.

Switch to comparison with Java

Search:

Benchmark ▲	Size ▲	Average Time	Unit	Error	Difference	% Difference
ClassArrayBenchmark.copy	10	0.05	us/op	± 2.60% (0.00)
ClassArrayBenchmark.copy	1000	5.92	us/op	± 0.53% (0.03)	-0.26	-4.23%
ClassArrayBenchmark.copy	100000	634.74	us/op	± 7.90% (50.16)
ClassArrayBenchmark.copyManual	10	0.06	us/op	± 2.92% (0.00)
ClassArrayBenchmark.copyManual	1000	8.03	us/op	± 1.82% (0.15)	+0.16	+2.06%
ClassArrayBenchmark.copyManual	100000	802.06	us/op	± 0.71% (5.70)
ClassArrayBenchmark.countFiltered	10	0.40	us/op	± 1.12% (0.00)
ClassArrayBenchmark.countFiltered	1000	46.94	us/op	± 3.07% (1.44)
ClassArrayBenchmark.countFiltered	100000	5670.62	us/op	± 3.57% (202.40)
ClassArrayBenchmark.countFilteredLocal	10	0.39	us/op	± 0.84% (0.00)	-0.01	-2.21%
ClassArrayBenchmark.countFilteredLocal	1000	46.44	us/op	± 1.99% (0.92)
ClassArrayBenchmark.countFilteredLocal	100000	5599.66	us/op	± 1.20% (67.01)	-125.05	-2.18%
ClassArrayBenchmark.countFilteredManual	10	0.39	us/op	± 1.93% (0.01)
ClassArrayBenchmark.countFilteredManual	1000	46.28	us/op	± 1.07% (0.50)
ClassArrayBenchmark.countFilteredManual	100000	5638.10	us/op	± 1.20% (67.56)

Kotlin Compiler

Jetbrains Idea下的默认kotlin安装

独立的compiler包下载解压的结果

E:\tool\kotlin\kotlinc 的目录

[.] [..] [bin] build.txt [lib] [license]

1 个文件 5 字节

E:\tool\kotlin\kotlinc\bin 的目录

[.] [..] kotlin kotlin.bat kotlinc kotlinc-js kotlinc-js.bat kotlinc-jvm

kotlinc-jvm.bat kotlinc.bat

8 个文件 7,900 字节

E:\tool\kotlin\kotlinc\lib 的目录

[.] [..] allopen-compiler-plugin.jar android-extensions-compiler.jar

kotlin-annotation-processing.jar kotlin-ant.jar kotlin-build-common-test.jar kotlin-build-common.jar

kotlin-compiler.jar kotlin-daemon-client.jar kotlin-jslib-sources.jar kotlin-jslib.jar

kotlin-preloader.jar kotlin-reflect.jar kotlin-runner.jar kotlin-runtime-sources.jar

kotlin-runtime.jar kotlin-test.jar noarg-compiler-plugin.jar

17 个文件 25,843,381 字节

E:\tool\kotlin\kotlinc\license 的目录

[.] [..] LICENSE.txt NOTICE.txt [third_party]

2 个文件 1,083 字节

E:\tool\kotlin\kotlinc\license\third_party 的目录

[.] [..] args4j_LICENSE.txt asm_license.txt closure-compiler_LICENSE.txt

dart_LICENSE.txt jshashtable_license.txt json_LICENSE.txt maven_LICENSE.txt pcollections_LICENSE.txt

prototype_license.txt rhino_LICENSE.txt

10 个文件 78,237 字节

2者是一样的，因此如果安装了idea的话，kotlin的环境默认就是可用的

if "%_KOTLIN_COMPILER%"=="" set _KOTLIN_COMPILER=org.jetbrains.kotlin.cli.jvm.K2JVMCompiler

if not "%JAVA_HOME%"=="" (

if exist "%JAVA_HOME%\bin\java.exe" set "_JAVACMD=%JAVA_HOME%\bin\java.exe"

)

if "%_JAVACMD%"=="" set _JAVACMD=java

rem We use the value of the JAVA_OPTS environment variable if defined

set _JAVA_OPTS=-Xmx256M -Xms32M

if not "%_KOTLIN_RUNNER%"=="" (

"%_JAVACMD%" %_JAVA_OPTS% "-Dkotlin.home=%_KOTLIN_HOME%" -cp "%_KOTLIN_HOME%\lib\kotlin-runner.jar" ^

org.jetbrains.kotlin.runner.Main %*

) else (

"%_JAVACMD%" %_JAVA_OPTS% -noverify -cp "%_KOTLIN_HOME%\lib\kotlin-preloader.jar" ^

org.jetbrains.kotlin.preloading.Preloader -cp "%_KOTLIN_HOME%\lib\kotlin-compiler.jar" ^

%_KOTLIN_COMPILER% %*

)

直接从命令行运行kotlin，最终的结果是转换成JAVA字节码的

kotlinc HelloWorld.kt -include-runtime -d HelloWorld.jar

$ java -jar HelloWorld.jar

kotlinc HelloWorld.kt -d HelloWorld.jar

java -cp $KOTLIN_HOME/lib/kotlin-runtime.jar:HelloWorld.jar HelloWorldKt

脚本方式执行

$ kotlinc-jvm -cp joda-time-2.9.4/joda-time-2.9.4.jar
Welcome to Kotlin version 1.1-M04 (JRE 1.8.0_66-internal-b17)
Type :help for help, :quit for quit
>>> import org.joda.time.DateTime
>>> DateTime.now()