Java正则表达式提取 Email 地址
import java.util.regex.Matcher; import java.util.regex.Pattern; import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; public class RegularExpression { public static void main(String[] args) throws IOException { // Simple expression to find a valid e-mail address in a file Pattern pattern = Pattern.compile("[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,4}"); // Read file, find valid mail addresses and print result File file = new File("test.txt"); BufferedReader in = new BufferedReader(new FileReader(file)); int lines = 0; int matches = 0; for (String line = in.readLine(); line != null; line = in.readLine()) { lines++; Matcher matcher = pattern.matcher(line.toUpperCase()); if (matcher.matches()) { System.out.println(lines + ": '" + line + "'"); matches++; } } // output of summary if (matches == 0) { System.out.println("No matches in " + lines + " lines"); } else { System.out.println("\n" + matches + " matches in " + lines + " lines"); } } }