java正则表达式匹配文本中想要的字符串

需求:获取一个本地文件中所有符合 $[MAKE_PACKAGE] 格式的字符串,并输出到另一个文件中.

public static void main(String[] args) throws Exception {

        loadVar("src/cn/don9/templates/Action.txt","src/cn/don9/templateVar/SysActionVar.txt");

    }

    public static void loadVar(String infilePath,String outfilePath) throws Exception{

        //定义set集合,实现去重效果

        Set<String> result = new HashSet<String>();

        //定义正则表达式

        String regex = "[\\$][\\[]\\w+[\\]]";

        Pattern pattern = Pattern.compile(regex);

        //读取文件

        File file = new File(infilePath);

        BufferedReader br = new BufferedReader(new FileReader(file));

        String line;

        while((line=br.readLine())!=null){

            //匹配文本中每行的字符串

            Matcher matcher = pattern.matcher(line);

            //发现匹配的字符串,存入set中

            while(matcher.find()){

                result.add(matcher.group());

            }

        }

        //加载输出文件

        File outfile = new File(outfilePath);

        BufferedWriter bw = new BufferedWriter(new FileWriter(outfile));

        for(String var:result){

            //写入字符串

            bw.write(var+"\r\n");

        }

        br.close();

        bw.close();

        System.out.println("读取完毕!");

    }

运行结果: