如何在 Java 正則表示式中找到符合所需模式的輸入序列中的子序列?
find() 方法找到與所需模式匹配的輸入序列中的子序列。該方法在 Matcher 類中可用,Matcher 類在 java.util.regex 程式包中可用。
下面提供了一個在 Java 正則表示式中演示方法 Matcher.find() 的程式。
示例
import java.util.regex.Matcher; import java.util.regex.Pattern; public class Demo { public static void main(String args[]) { Pattern p = Pattern.compile("Sun"); Matcher m = p.matcher("The Earth revolves around the Sun"); System.out.println("Subsequence: Sun"); System.out.println("Sequence: The Earth revolves around the Sun"); if (m.find()) System.out.println("
Subsequence found"); else System.out.println("
Subsequence not found"); } }
輸出
Subsequence: Sun Sequence: The Earth revolves around the Sun Subsequence found
現在讓我們理解一下上面的程式。
在字串序列“地球繞著太陽轉”中搜索子序列“太陽”。然後使用 find() 方法查詢子序列是否在輸入序列中,並列印所需結果。演示此內容的程式碼片段如下所示:
Pattern p = Pattern.compile("Sun"); Matcher m = p.matcher("The Earth revolves around the Sun"); System.out.println("Subsequence: Sun" ); System.out.println("Sequence: The Earth revolves around the Sun" ); if (m.find()) System.out.println("
Subsequence found"); else System.out.println("
Subsequence not found");
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