Java中的 Matcher reset(CharSequence) 方法及示例

Matcher 类的reset(CharSequence input)方法用于重置此匹配器，并将作为参数传递的输入字符串插入此匹配器。

句法：

public Matcher reset(CharSequence input)

参数：此方法接受参数输入，即重置后要插入匹配器的字符串。

返回值：此方法在使用此输入重置后返回此匹配器。

下面的示例说明了 Matcher.reset() 方法：

示例 1：

// Java code to illustrate reset() method
  
import java.util.regex.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // Get the regex to be checked
        String regex = "Geeks";
  
        // Create a pattern from regex
        Pattern pattern
            = Pattern.compile(regex);
  
        // Get the String to be matched
        String stringToBeMatched = "GeeksForGeeks";
  
        // Create a matcher for the input String
        Matcher matcher
            = pattern
                  .matcher(stringToBeMatched);
  
        // Get the current matcher state
        System.out.println("Current Matcher: "
                           + matcher.toMatchResult());
  
        // Reset the Matcher using reset() method
        String newStringToBeMatched
            = "GeeksGeeksGeeks";
        matcher = matcher
                      .reset(newStringToBeMatched);
  
        // Get the current matcher state
        System.out.println("Current Matcher after Reset: "
                           + matcher.toMatchResult());
    }
}

输出：

Current Matcher: java.util.regex.Matcher[pattern=Geeks region=0,13 lastmatch=]
Current Matcher after Reset: java.util.regex.Matcher[pattern=Geeks region=0,15 lastmatch=]

示例 2：

// Java code to illustrate reset() method
  
import java.util.regex.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // Get the regex to be checked
        String regex = "GFG";
  
        // Create a pattern from regex
        Pattern pattern = Pattern.compile(regex);
  
        // Get the String to be matched
        String stringToBeMatched
            = "GFGFGFGFGFGFGFGFGFG";
  
        // Create a matcher for the input String
        Matcher matcher
            = pattern
                  .matcher(stringToBeMatched);
  
        // Get the current matcher state
        System.out.println("Current Matcher: "
                           + matcher.toMatchResult());
  
        // Reset the Matcher using reset() method
        String newStringToBeMatched
            = "GFG means GeeksForGeeks";
        matcher = matcher
                      .reset(newStringToBeMatched);
  
        // Get the current matcher state
        System.out.println("Current Matcher after Reset: "
                           + matcher.toMatchResult());
    }
}

输出：

Current Matcher: java.util.regex.Matcher[pattern=GFG region=0,19 lastmatch=]
Current Matcher after Reset: java.util.regex.Matcher[pattern=GFG region=0,23 lastmatch=]

参考： Oracle 文档