Java Matcher usePattern(Pattern)用法及代碼示例

Matcher類的usePattern()方法用於獲取此匹配器要匹配的模式。

用法:

public Matcher usePattern(Pattern newPattern)

參數：此方法采用參數newPattern，它是要設置的新模式。

返回值：此方法返回具有新Pattern的Matcher。

異常：如果newPattern為null，則此方法引發IllegalArgumentException。

下麵的示例說明Matcher.usePattern()方法：

示例1:

// Java code to illustrate usePattern() 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 new Pattern 
        String newPattern = "GFG"; 
  
        // Get the Pattern using pattern method 
        System.out.println("Old Pattern: "
                           + matcher.pattern()); 
  
        // Set the newPattern using usePattern() method 
        matcher = matcher 
                      .usePattern( 
                          Pattern 
                              .compile(newPattern)); 
  
        // Get the Pattern 
        // using pattern method 
        System.out.println("New Pattern: "
                           + matcher.pattern()); 
    } 
}

輸出：

Old Pattern: Geeks
New Pattern: GFG

示例2:

// Java code to illustrate usePattern() 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 
            = patter 
                  n.matcher(stringToBeMatched); 
  
        // Get the new Pattern 
        String newPattern = "Geeks"; 
  
        // Get the Pattern using pattern method 
        System.out.println("Old Pattern: "
                           + matcher.pattern()); 
  
        // Set the newPattern using usePattern() method 
        matcher = matcher 
                      .usePattern( 
                          Pattern 
                              .compile(newPattern)); 
  
        // Get the Pattern 
        // using pattern method 
        System.out.println("New Pattern: "
                           + matcher.pattern()); 
    } 
}

輸出：

Old Pattern: GFG
New Pattern: Geeks

參考： Oracle Doc

相關用法

注：本文由純淨天空篩選整理自Kirti_Mangal大神的英文原創作品 Matcher usePattern(Pattern) method in Java with Examples。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。