Scala正則表達式replaceAllIn與特殊字符完全匹配

Question

下面我試圖用替換字符串xxx替換精確的搜索字符串。我有類似於Java日誌消息的字符串原始。正如你可以看到，如果搜索字符串是「變量」，我可以用xxx成功替換它，但是當搜索字符串是「variable.method（）」或「variable.method2（）」時，我無法替換它。我在這裏做錯了什麼？

val original = """variable+ " is in " + variable.method() + " and " + variable.method2()""" 
val replaceStr = "xxx" 
val searchStr = "variable.method()" // This can change like in the output below 
val variableExtracter = ("(?<=^|\\s|\\+)"+searchStr+"(?=\\s|$|\\+)").r 
print("Search string : " + searchStr + "\n") 
print("Original :" + original + "\n") 
val formatted = variableExtracter.replaceAllIn(original, replaceStr) 
print("Formatted :" + formatted + "\n") 

Output: 

Search string : variable //CORRECT OUTPUT 
Original :variable+ " is in " + variable.method() + " and " + variable.method2() 
Formatted :xxx+ " is in " + variable.method() + " and " + variable.method2() 
--- 
Search string : variable.method() 
Original :variable+ " is in " + variable.method() + " and " + variable.method2() 
Formatted :variable+ " is in " + variable.method() + " and " + variable.method2() 
//EXPECTED OUTPUT: variable+ " is in " + xxx + " and " + variable.method2() 
--- 
Search string : variable.method2() 
Original :variable+ " is in " + variable.method() + " and " + variable.method2() 
Formatted :variable+ " is in " + variable.method() + " and " + variable.method2() 
//EXPECTED OUTPUT:variable+ " is in " + variable.method() + " and " + xxx 
--- 
Search string : variable.method() 
Original :variable.method()+ " has " + variable + " and " + variable.method2() 
Formatted :variable.method()+ " has " + variable + " and " + variable.method2() 
//EXPECTED OUTPUT:xxx+ " has " + variable + " and " + variable.method2() 

Answer 1

編輯：

可以使用Java Pattern quote methodPattern.quote(searchStr)來包裝你與\Q和\E字符串。

scala> import java.util.regex.Pattern 
import java.util.regex.Pattern 

scala> val variableExtracter = ("(?<=^|\\s|\\+)"+Pattern.quote(searchStr)+"(?=\\s|$|\\+)").r 
variableExtracter: scala.util.matching.Regex = (?<=^|\s|\+)\Qvariable.method2()\E(?=\s|$|\+) 

scala> print("Search string : " + searchStr + "\n") 
Search string : variable.method2() 

scala> print("Original :" + original + "\n") 
Original :variable+ " is in " + variable.method() + " and " + variable.method2() 

scala> val formatted = variableExtracter.replaceAllIn(original, replaceStr) 
formatted: String = variable+ " is in " + variable.method() + " and " + xxx 

scala> print("Formatted :" + formatted + "\n") 
Formatted :variable+ " is in " + variable.method() + " and " + xxx 

scala> val searchStr = "variable.method()" 
searchStr: java.lang.String = variable.method() 

scala> val variableExtracter = ("(?<=^|\\s|\\+)"+Pattern.quote(searchStr)+"(?=\\s|$|\\+)").r 
variableExtracter: scala.util.matching.Regex = (?<=^|\s|\+)\Qvariable.method()\E(?=\s|$|\+) 

scala> val formatted = variableExtracter.replaceAllIn(original, replaceStr) 
formatted: String = variable+ " is in " + xxx + " and " + variable.method2()