Java中的Matcher regionStart()方法与示例
java.util.regex.Matcher类表示执行各种匹配操作的引擎。该类没有构造函数,可以使用类java.util.regex.Pattern的matchs()方法创建/获取该类的对象。
这个(Matcher)类的regionStart()方法返回一个整数值,该整数值表示当前匹配器对象的起始索引。
例子1
import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegionStartExample { public static void main(String[] args) { //Regular expression to accepts 6 to 10 characters String regex = "[#]"; System.out.println("Enter a string: "); Scanner sc = new Scanner(System.in); String input = sc.nextLine(); //Creating a pattern object Pattern pattern = Pattern.compile(regex); //Creating a Matcher object Matcher matcher = pattern.matcher(input); //Setting region to the input string matcher.region(2, 4); //Switching to transparent bounds if(matcher.find()) { System.out.println("Match found"); } else { System.out.println("Match not found"); } System.out.println("Starting of the region: "+ matcher.regionStart()); } }
输出结果
Enter a string: #sample text Match not found Starting of the region: 2
例子2
import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegionStartExample { public static void main(String[] args) { String regex = "(.*)(\\d+)(.*)"; String input = "124 This is a sample Text, 1234, with numbers in between."; //Creating a pattern object Pattern pattern = Pattern.compile(regex); //Creating a Matcher object Matcher matcher = pattern.matcher(input); //Setting the region of the matcher matcher.region(5, 20); if(matcher.matches()) { System.out.println("Match found"); } else { System.out.println("Match not found"); } System.out.print("Start of the region: "+matcher.regionStart()); } }
输出结果
Match not found Start of the region: 5