追加写文件

对一个文件持续的写入内容：

public static String createFile(String filePath , String content) {
        File file = new File(filePath);
        FileOutputStream fos = null;
        OutputStreamWriter osw = null;

        try {
            if (!file.exists()) {
                boolean hasFile = file.createNewFile();
                if(hasFile){
                    System.out.println("file not exists, create new file");
                }
                fos = new FileOutputStream(file);
            } else {
                System.out.println("file exists");
                fos = new FileOutputStream(file, true);
            }

            osw = new OutputStreamWriter(fos, "utf-8");
            osw.write(content); //写入内容
            osw.write("\r\n");  //换行
        } catch (Exception e) {
            e.printStackTrace();
        }finally {   //关闭流
            try {
                if (osw != null) {
                    osw.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if (fos != null) {
                    fos.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return filePath + "已创建完成";
    }