java笔试之参数解析（正则匹配）

package test;

import java.util.ArrayList;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;


//使用正则表达式
public class exam19 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        // result存储经过正则表达式判定后的字符串
        ArrayList<String> result = new ArrayList<String>();
        String reg = "(\".*?\")|([a-zA-Z_0-9:/\\\\]+)";// *?非贪婪匹配，最少重复;/\\\\来匹配\\
        Pattern pattern = Pattern.compile(reg);
        while (scanner.hasNext()) {
            String string = scanner.nextLine();
            // 获取matcher对象
            Matcher matcher = pattern.matcher(string);
            String tokeString = "";
            int pos = 0;
            while (pos < string.length()) {
                //匹配定位：开始到结束
                matcher.region(pos, string.length());
                if (matcher.lookingAt()) {
                    // group(0)表示整个串；
                    // group(1)只符合第一个括号的匹配；
                    // group(2)只符合第二个括号匹配
                    if (matcher.group(1) != null) {
                        result.add(matcher.group(1).replaceAll("\"", ""));
                    } else if (matcher.group(2) != null) {
                        result.add(matcher.group(2));
                    }
                    pos = matcher.end();//总匹配的最后索引
                } else {
                    pos++;
                }

            }
            System.out.println(result.size());
            for (String tok : result) {
                System.out.println(tok);
            }
        }
        scanner.close();
    }
}