Java从IOUtils的InputStrem(特别是copyBytes)动态写入字符串数组

the documentation from copyBytes (共) IOUtils

复制字节:

public static void copyBytes(InputStream in,
                             OutputStream out,
                             int buffSize,
                             boolean close) throws IOException

从一个流复制到另一个流。

参数:

in - InputStrem to read from
out - OutputStream to write to
buffSize - the size of the buffer
close - whether or not close the InputStream and OutputStream at the end. The streams are closed in the finally clause.

抛出:

IOException

因此,考虑到这些信息,我得到了这样的数据结构:

List<String> inputLinesObject = IOUtils.readLines(in, "UTF-8");

复制字节 方法

然而,以下是我调用 复制字节 方法:

IOUtils.copyBytes(in, inputLinesObject, 4096, false);

inputLinesObject ,我想把我的可扩展数组列表放在这里,它可以收集数据并将其转换为字符串格式-但我现在这样做的方式并不正确-我不知何故被卡住了-我看不到以字符串数组列表格式收集数据的正确方法( inputSteam 这是否意味着 byteArray ?).

HDFS and-应该(尽管目前没有)将它们输出到字符串数组列表中-最终将使用 System.out.println .

// this concatenates output to terminal from hdfs 
public static void main(String[] args) throws IOException {

    // supply this as input
    String uri = args[0];

    // reading in from hdfs
    Configuration conf = new Configuration();
    FileSystem fs = FileSystem.get(URI.create(uri), conf);
    FSDataInputStream in = null;


    // create arraylist for hdfs file to flow into
    //List<String> inputLinesObject = new ArrayList<String>();
    List<String> inputLinesObject = IOUtils.readLines(in, "UTF-8");


    // TODO: how to make this go to a file rather than to the System.out?
    try
    {
        in = fs.open(new Path(uri));
        // The way:
        IOUtils.copyBytes(in, inputLinesObject, 4096, false);

    }
    finally{
        IOUtils.closeStream(in);
    }