java如何合并多个文件

Java中合并子文件最容易想到的就是利用BufferedStream进行读写。

具体的实现方式如下，代码很详细，供各位参考学习。

1、首先创建mergeFiles方法，接收字符串数组和字符串参数，并完成文件合并功能

public static boolean mergeFiles(String[] fpaths, String resultPath) {
    if (fpaths == null || fpaths.length < 1 || TextUtils.isEmpty(resultPath)) {
        return false;
    }
    if (fpaths.length == 1) {
        return new File(fpaths[0]).renameTo(new File(resultPath));
    }

    File[] files = new File[fpaths.length];
    for (int i = 0; i < fpaths.length; i ++) {
        files[i] = new File(fpaths[i]);
        if (TextUtils.isEmpty(fpaths[i]) || !files[i].exists() || !files[i].isFile()) {
            return false;
        }
    }

    File resultFile = new File(resultPath);

    try {
        int bufSize = 1024;
        BufferedOutputStream outputStream = new BufferedOutputStream(new FileOutputStream(resultFile));
        byte[] buffer = new byte[bufSize];

        for (int i = 0; i < fpaths.length; i ++) {
            BufferedInputStream inputStream = new BufferedInputStream(new FileInputStream(files[i]));
            int readcount;
            while ((readcount = inputStream.read(buffer)) > 0) {
                outputStream.write(buffer, 0, readcount);
            }
            inputStream.close();
        }
        outputStream.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
        return false;
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    }

    for (int i = 0; i < fpaths.length; i ++) {
        files[i].delete();
    }

    return true;
}

2、然后在main函数中对mergeFiles方法进行调用，使用时传入多个文件的地址数组，并传入输出文件地址即可。

public static void main(String[] args) {
          mergeFiles(new String[]{"D:/in_1.txt", "D:/in_2.txt", "D:/in_3.txt"}, "D:/output.txt");
}