Scala学习笔记9 (misc)
9. misc
9.1. json
Scala-json
9.2. Configgy
http://www.lag.net/configgy/
简单配置及logging：
----------------------------
log {
filename = "/var/log/pingd.log"
roll = "daily"
level = "debug"
}
hostname = "pingd.example.com"
port = 3000
----------------------------
val conf = net.lag.configgy.Configgy.configure("/etc/pingd.conf").config
val hostname = conf.getString("hostname", "localhost")
val port = conf.getInt("port", 3000)
9.3. 正则表达式regex
例子1：完全匹配
//将字符串转为scala.util.matching.Regex
val pattern = "^[a-z0-9._%\\-+]+@(?:[a-z0-9\\-]+\\.)+[a-z]{2,4}$"
val emailRegex = pattern.r // 或者 new scala.util.matching.Regex(pattern)
//emailRegex.pattern=>java.util.regex.Pattern 使用java的Pattern
emailRegex.pattern.matcher("[email protected]").matches // true
例子2：查找匹配部分
val p = "[0-9]+".r
p.findAllIn("2 ad 12ab ab21 23").toList // List(2, 12, 21, 23)
p.findFirstMatchIn("abc123xyz").get // scala.util.matching.Regex.Match = 123
更多例子如下：
定义：
val r1 = "(\\d+) lines".r // syntactic sugar val r2 = """(\d+) lines""".r // using triple-quotes to preserve backslashes
或者
import scala.util.matching.Regex val r3 = new Regex("(\\d+) lines") // standard val r4 = new Regex("""(\d+) lines""", "lines") // with named groups
search和replace（java.lang.String的方法）：
"99 lines" matches "(\\d+) lines" // true
"99 Lines" matches "(\\d+) lines" // false
"99 lines" replace ("99", "98") // "98 lines"
"99 lines lines" replaceAll ("l", "L") // 99 Lines Lines
search（regex的方法）：
"\\d+".r findFirstIn "99 lines" // Some(99)
"\\w+".r findAllIn "99 lines" // iterator(长度为2)
"\\s+".r findPrefixOf "99 lines" // None
"\\s+".r findPrefixOf " 99 lines" // Some( )
val r4 = new Regex("""(\d+) lines""", "g1") // with named groups
r4 findFirstMatchIn "99 lines-a" // Some(99 lines)
r4 findPrefixMatchOf "99 lines-a" // Some(99 lines)
val b = (r4 findFirstMatchIn "99 lines").get.group("g1") // "99"
match（regex的方法）：
val r1 = "(\\d+) lines".r
val r4 = new Regex("""(\d+) lines""", "g1")
val Some(b) = r4 findPrefixOf "99 lines" // "99 lines" for { line <- """|99 lines-a |99 lines |pass |98 lines-c""".stripMargin.lines } line match { case r1(n) => println("Has " + n + " Lines.") // "Has 99 Lines."
case _ => }
for (matched <- "(\\w+)".r findAllIn "99 lines" matchData)
println("Matched from " + matched.start + " to " + matched.end)
输出：
Matched from 0 to 2
Matched from 3 to 8
replace（regex的方法）：
val r2 = """(\d+) lines""".r // using triple-quotes to preserve backslashes
r2 replaceFirstIn ("99 lines-a", "aaa") // "aaa-a"
r2 replaceAllIn ("99 lines-a, 98 lines-b", "bbb") // "bbb-a, bbb-b"
其他：使用正则表达式定义变量
val regex = "(\\d+)/(\\d+)/(\\d+)".r
val regex(year, month, day) = "2010/1/13"
// year: String = 2010
// month: String = 1
// day: String = 13
9.4. GUI
9.4.1. java方式
import javax.swing.JFrame
var jf = new JFrame("Hello!")
jf.setSize(800, 600)
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)
jf.setVisible(true)
9.4.2. scala方式
import swing._, swing.Swing._
object Swing1 extends SimpleGUIApplication { // scala2.7
def top = new MainFrame { // 必须实现top方法
title = "窗口1"
preferredSize = (400, 300)
val label = new Label("hello world cn中文")
contents = new BorderPanel {
layout(label) = BorderPanel.Position.Center
}
}
}