如何使用Storm将输出写入文件

Question

Kaveen,bigdata,29
varadha,cshart,30
vignesh,winrt,21

输出。

varadha,cshart,30
vignesh,winrt,21
Kaveen,bigdata,29
varadha,cshart,30
Kaveen,bigdata,29
Kaveen,bigdata,29
vignesh,winrt,21

我想写的输出文件与inputfile完全相似，但顺序不是问题。我怎样才能做到，请帮帮我。

Answer 1

我也面临着同样的问题，所以找到了以下的解决方法。

在Spout中，当您读取文件时，在open（）方法中创建FileReader对象，因为此时它会初始化worker节点的reader对象。并在nextTuple（）方法中使用该对象。
（带有一个喷口和一个螺栓）

下面是open（）和nextTuple方法的代码：

    public void open(Map conf, TopologyContext context,
            SpoutOutputCollector collector) {
            try {
            this.context = context;
            File file = new File(filename);
            this.fileReader = new FileReader(file);
        } catch (FileNotFoundException e) {
            throw new RuntimeException("Error reading file ["+ filename + "]");
        }
        this.collector = collector;
    }

    public void nextTuple() {
        /**
         * The nextuple it is called forever, so if we have been readed the file
         * we will wait and then return
         */
        if (completed) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                // Do nothing
            }
            return;
        }
        String str;
        BufferedReader reader = new BufferedReader(fileReader);
        try {
            // Read all lines
            while ((str = reader.readLine()) != null) {
                /**
                 * By each line emit a new value with the line as a their
                 */
                this.collector.emit(new Values(str), str);
            }
        } catch (Exception e) {
            throw new RuntimeException("Error reading tuple", e);
        } finally {
            completed = true;
        }
    }

Kaveen,bigdata,29
varadha,cshart,30
vignesh,winrt,21