java如何将两文本内容按照要求，合并为新的文本

/*
 *读取文本1的方法，将读取到的数据存入HashMap里面后续方便提取
 *读取文本2也是这个方法，需要修改下文本2的读取路径
 */

public static HashMap<Integer, String> readFile1() {        
        HashMap<Integer, String> map = new HashMap<Integer,String>();
 
        //当前文本放的位置，根据需求自己修改

        String path = "C:/Users/xx/Desktop/1.txt";
        try {
            FileInputStream in = new FileInputStream(path);
            InputStreamReader inReader = new InputStreamReader(in, "UTF-8");
            BufferedReader bufReader = new BufferedReader(inReader);
            String line = null;
            int i = 0;
            while ((line = bufReader.readLine()) != null) {
                System.out.println("我是文本1======>"+line);
                for (; i < 5;) {
                    map.put(i, line);
                    i++;
                    break;
                }
            }    
        } catch (FileNotFoundException e) {
            System.out.println("文件没有找到");
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            System.out.println("无法转义");
            e.printStackTrace();
        } catch (IOException e) {
            System.out.println("文件读取失败");
            e.printStackTrace();
        }
        return map;
    } 

/*
 * 写入文本方法
 * 参数a-文本1读取的内容；参数b-文本2读取的内容；price是要求添加的参数
 */
public static void writeFile(String a, String b, int price) {
        String path = "C:/Users/xx/Desktop/3.txt";
        String slo = a+","+b+","+price+"|";
        System.out.println("存入的数据" + slo);
        File filename = new File(path);
        try {
            FileWriter out = new FileWriter(filename, true);
            BufferedWriter write = new BufferedWriter(out);
            out.write(slo);
            write.newLine();
            out.flush();
            out.close();
        } catch (IOException e) {
            System.out.println("文件写入失败");
            e.printStackTrace();
        }
    }
//方法结束

/*
 *2019.12.6 新增 xy
 *拼接文本的主方法
 */
public static void main(String[] args) {
        HashMap<Integer, String> map1 = readFile1();
        HashMap<Integer, String> map2 = readFile2();
        String a = "";
        String b = "";
        for (int i = 0; i < 5; i++) {
            a = map1.get(i);
            b = map2.get(i);
            writeFile(a, b, 30);
        }
    }

String slo = a + "\r\n";