将文件拆分为多个文件 [英] Split file into multiple files

问题描述

我想剪切一个文本文件.我想将文件切成 50 行 x 50 行.

I want to cut a text file. I want to cut the file 50 lines by 50 lines.

例如，如果文件是 1010 行，我会恢复 21 个文件.

For example, If the file is 1010 lines, I would recover 21 files.

我知道如何计算文件数和行数，但我一写就行不通.

I know how to count the number of files, the number of lines but as soon as I write, it's doesn't work.

我使用 Camel Simple (Talend) 但它是 Java 代码.

I use the Camel Simple (Talend) but it's Java code.

private void ExtractOrderFromBAC02(ProducerTemplate producerTemplate, InputStream content, String endpoint, String fileName, HashMap<String, Object> headers){
        ArrayList<String> list = new ArrayList<String>();
        BufferedReader br = new BufferedReader(new InputStreamReader(content));
        String line;
        long numSplits = 50;                
        int sourcesize=0;
        int nof=0;
        int number = 800;
        try {               
            while((line = br.readLine()) != null){
                    sourcesize++;
                    list.add(line);
            }

         System.out.println("Lines in the file: " + sourcesize);    

        double numberFiles = (sourcesize/numSplits);  
        int numberFiles1=(int)numberFiles;  
                if(sourcesize<=50)   {  
                  nof=1;  
                }  
                else  {  
                     nof=numberFiles1+1;  
                }  
       System.out.println("No. of files to be generated :"+nof);

       for (int j=1;j<=nof;j++) {  
                 number++;
                 String  Filename = ""+ number;
                 System.out.println(Filename);

            StringBuilder builder = new StringBuilder();
            for (String value : list) {
                builder.append("/n"+value);
            }

             producerTemplate.sendBodyAndHeader(endpoint, builder.toString(), "CamelFileName",Filename);
        }

             }  

         } catch (IOException e) {
                e.printStackTrace();
         }
            finally{
                try {
                    if(br != null)br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

对于不了解Camel的人，这一行是用来发送文件的:

For people who don't know Camel, this line is used to send the file:

producerTemplate.sendBodyAndHeader (endpoint, line.toString (), "CamelFileName" Filename);

endpoint ==> Destination(其他代码也可以)

endpoint ==> Destination (it's ok with another code)

line.toString() ==> 值

line.toString () ==> Values

然后是文件名(用其他代码就可以了)

And then the file name (it's ok with another code)

推荐答案

你先数行数

while((line = br.readLine()) != null){
                    sourcesize++; }

然后你在文件的末尾:你什么都没读

and then you're at the end of the file: you read nothing

for (int i=1;i<=numSplits;i++)  {  
                while((line = br.readLine()) != null){

在再次阅读之前，您必须回到文件的开头.

You have to seek back to the start of the file before reading again.

但那是浪费时间&电源，因为您将读取文件两次

But that's a waste of time & power because you'll read the file twice

最好一次性读取文件，将其放入List(可调整大小)，然后使用存储在内存中的行进行拆分.

It's better to read the file once and for all, put it in a List<String> (resizable), and proceed with your split using the lines stored in memory.

似乎您听从了我的建议并偶然发现了下一个问题.您可能应该问另一个问题，嗯……这会创建一个包含所有行的缓冲区.

seems that you followed my advice and stumbled on the next issue. You should have maybe asked another question, well... this creates a buffer with all the lines.

for (String value : list) {
                builder.append("/n"+value);
            }

你必须使用列表上的索引来构建小文件.

You have to use indexes on the list to build small files.

for (int k=0;k<numSplits;k++) {  
      builder.append("/n"+list[current_line++]);

current_line 是文件中的全局行计数器.这样你每次创建 50 行不同的文件:)

current_line being the global line counter in your file. That way you create files of 50 different lines each time :)

这篇关于将文件拆分为多个文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！