Java中的 Matcher hasAnchoringBounds() 方法及示例

Matcher 类的hasAnchoringBounds()方法用于检查此匹配器是否具有锚定边界。通过锚定边界，这意味着如果锚定边界设置为 true，则匹配器将匹配 ^ 和 $ 等锚点以获取匹配。此方法返回一个布尔值，说明相同。

句法：

public boolean hasAnchoringBounds()

参数：此方法不带参数。

返回值：此方法返回一个布尔值，说明此匹配器是否具有锚定边界

下面的示例说明了 Matcher.hasAnchoringBounds() 方法：

示例 1：

// Java code to illustrate hasAnchoringBounds() 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 Geeks for For Geeks Geek";
  
        // Create a matcher for the input String
        Matcher matcher
            = pattern.matcher(stringToBeMatched);
  
        // Check if this matcher has anchoring bounds or not
        // using hasAnchoringBounds() method
        System.out.println("Does this matcher"
                           + " has anchoring bounds: "
                           + matcher.hasAnchoringBounds());
    }
}

输出：

Does this matcher has anchoring bounds: true

示例 2：

// Java code to illustrate hasAnchoringBounds() method
  
import java.util.regex.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // Get the regex to be checked
        String regex = "(F*F)";
  
        // Create a pattern from regex
        Pattern pattern = Pattern.compile(regex);
  
        // Get the String to be matched
        String stringToBeMatched
            = " FGF GFG GFG FGF";
  
        // Create a matcher for the input String
        Matcher matcher
            = pattern.matcher(stringToBeMatched);
  
        // set the anchoring bounds to true
        matcher = matcher
                      .useAnchoringBounds(false);
  
        // Check if this matcher has anchoring bounds or not
        // using hasAnchoringBounds() method
        System.out.println("Does this matcher"
                           + " has anchoring bounds: "
                           + matcher.hasAnchoringBounds());
    }
}

输出：

Does this matcher has anchoring bounds: false

参考： https://docs.oracle.com/javase/9/docs/api/ Java/util/regex/Matcher.html#hasAnchoringBounds–