code: public static void convertPKUtoCWS(String inputFolder, String outputFile, final int begin, final int end) throws IOException
      {
          final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(outputFile), "UTF-8"));
          CorpusLoader.walk(inputFolder, new CorpusLoader.Handler()
                            {
                                int doc = 0;
  
                                @Override
                                public void handle(Document document)
                                {
                                    ++doc;
                                    if (doc < begin || doc > end) return;
                                    try
                                    {
                                        List<List<Word>> sentenceList = convertComplexWordToSimpleWord(document.getComplexSentenceList());
                                        if (sentenceList.size() == 0) return;
                                        for (List<Word> sentence : sentenceList)
                                        {
                                            if (sentence.size() == 0) continue;
                                            int index = 0;
                                            for (IWord iWord : sentence)
                                            {
                                                bw.write(iWord.getValue());
                                                if (++index != sentence.size())
                                                {
                                                    bw.write(' ');
                                                }
                                            }
                                            bw.newLine();
                                        }
                                    }
                                    catch (IOException e)
                                    {
                                        e.printStackTrace();
                                    }
                                }
                            }
  
          );
          bw.close();
      }
docs: 将人民日报格式的分词语料转化为空格分割的语料
  
  @param inputFolder 输入人民日报语料的上级目录(该目录下的所有文件都是一篇人民日报分词文章)
  @param outputFile  输出一整个CRF训练格式的语料
  @param begin       取多少个文档之后
  @param end
  @throws IOException 转换过程中的IO异常