如何打印所有从一个文件中的字符串匹配给定模式？

解决方法

下面的示例显示了如何打印所有从文件与Util.regex类的Patternname.matcher()方法匹配给定模式的字符串。

import java.util.regex.*;
import java.io.*;

public class ReaderIter {
   public static void main(String[] args) 
   throws IOException {
      Pattern patt = Pattern.compile("[A-Za-z][a-z]+");
      BufferedReader r = new BufferedReader
      (new FileReader("ReaderIter.java"));
      String line;
      while ((line = r.readLine()) != null) {
         Matcher m = patt.matcher(line);
         while (m.find()) {
            System.out.println(m.group(0));
            int start = m.start(0);
            int end = m.end(0);
            Use CharacterIterator.substring(offset, end);
            System.out.println(line.substring(start, end));
         }
      }
   }
}

结果

上面的代码示例将产生以下结果。

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