一篇文章带你了解Python和Java的正则表达式对比_Python

简单批量替换

举例：将and 批量替换为&&

Python实现

				?

									import re

									def transformSimple(fromRegex, toText, inText):

									    return re.sub(fromRegex, toText,inText, flags =re.I)

									if __name__ == "__main__":

									    inText = "x =1 and y =2"

									    fromRegex = " and "

									    toText = " && "

									    outText = transformSimple(fromRegex,toText,inText )

									    print(outText)

									    ## OUTPUT： x =1 && y =2

Java实现

				?

									import java.util.*;

									import java.util.regex.*;

									public class RegexTest {

									    private static String transformSimple(String regexPattern, String replText, String inText){

									        return Pattern.compile(regexPattern, Pattern.CASE_INSENSITIVE).matcher(inText).replaceAll(replText);

									    }

									    public static void main(String[] args) {

									        String input = "x =1 and y =2";

									        String patternString =" and ";

									        String toText = " && ";

									        String outText ="";

									        outText = transformSimple(patternString, toText, input);

									        System.out.println("RESULT: " + outText);

									}

									// RESULT: x =1 && y =2

复杂模板替换

举例：将x in (1,2)批量替换为[1,2].contains(x)

分析：模板化

输入分组捕获 (\S+)\s+in\s*\((.+?)\)
输出分组填写 [@2].contains(@1) – @1和@2分别对应分组捕获中的第1组和2组。

Python实现

				?

									import re

									def transformComplex(fromRegex, toText, inText):

									    regObj = re.compile(fromRegex, flags =re.I)

									    for match in regObj.finditer(inText):

									        index = 1

									        outText = toText

									        for group in match.groups():

									            outText = outText.replace("@"+str(index), group)

									            index +=1

									        inText = inText.replace(match.group(0), outText)

									    return inText

									if __name__ == "__main__":

									    fromRegex = "(\S+)\s+in\s*\((.+?)\)"

									    toText = "[@2].contains(@1)"

									    inText = "x in (1,2) and y in (3,4)"

									    outText22 = transformComplex(fromRegex, toText, inText)

									    print(outText22)

									    ## OUTPUT: [1,2].contains(x) and [3,4].contains(y)

Java实现

				?

									import java.util.*;

									import java.util.regex.*;

									public class RegexTest {

									    private static String transformComplex(String regexPattern, String replText, String inText){

									        Pattern pattern = Pattern.compile(regexPattern, Pattern.CASE_INSENSITIVE);

									        Matcher matcher = pattern.matcher(inText);

									        String outText ="";

									        while (matcher.find()){

									            outText =  replText;

									            for (int i =1; i <= matcher.groupCount(); i++){

									                outText = outText.replace("@"+i, matcher.group(i));

									            }

									            inText = inText.replace(matcher.group(0), outText);

									        }

									        return inText;

									    }

									    public static void main(String[] args) {

									        String input = "x in (1,2) and y in (3,4)";

									        String patternString ="(\\S+)\\s+in\\s*\\((.+?)\\)";

									        String toText = "[@2].contains(@1)";

									        String outText ="";

									        outText = transformComplex(patternString, toText, input);

									        System.out.println("RESULT: " + outText);

									    }

									}

									// RESULT: [1,2].contains(x) and [3,4].contains(y)