java9のインストールとjshellの使い方を詳しく解説

/Library/Java/JavaVirtualMachines/jdk-9.jdk/Contents/Home

bin ./java -version
java version "9"
Java(TM) SE Runtime Environment (build 9+181)
Java HotSpot(TM) 64-Bit Server VM (build 9+181, mixed mode)

 bin ./jshell
| 欢迎使用 JShell -- 版本 9
| 要大致了解该版本, 请键入: /help intro

jshell>

jshell> "1,2,3,,4".split(",")
$2 ==> String[5] { "1", "2", "3", "", "4" }

jshell> " a b ".trim()
$3 ==> "a b"

jshell> /imports
| import java.io.*
| import java.math.*
| import java.net.*
| import java.nio.file.*
| import java.util.*
| import java.util.concurrent.*
| import java.util.function.*
| import java.util.prefs.*
| import java.util.regex.*
| import java.util.stream.*

jshell> String hello(){return "htllo";}
| 已创建 方法 hello()

jshell> String hello(){return "hello";}
| 已修改 方法 hello()

jshell>

jshell>

jshell> /methods
| String hello()

jshell> hello()
$7 ==> "hello"

jshell> /list

 1 : int a = 1;
 2 : "1,2,3,,4".split(",")
 3 : " a b ".trim()
 4 : new Date()
 6 : String hello(){return "hello";}
 7 : hello()
 8 : 1/0