简介
和OP聊完,简单说一下OP的要求:
1- 从特定文件夹读取文件,文件通常是 Unicode 作为文本文件。
2-文件将在问题中的OP算法中处理,算法的结果应再次保存在Unicode文件中(后来OP要求将其保存为Excel文件(.XLS),因为Unicode与Excel兼容)
解决方案
这可以通过以下步骤解决:
步骤 1 我们定义(声明)我们的工作空间
步骤 2 如果不存在,我们在工作空间中创建输出文件夹
第 3 步 我们读取工作空间文件夹中的所有现有文件并在算法中处理它们。
步骤 4 每个文件的结果将保存为输出文件夹中的 Excel 文件。
代码
首先您需要导入 POI 包,这将允许您创建 XLS 表。我已经下载了这个 poi/poi-3.5-FINAL.jar.zip( 1,372 k) 并且应该将以下导入添加到您的代码中。
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFRow;
接下来您将以下代码添加到您的代码中,这是可自我解释的代码:
final static String WORKSPACE = "C:/testfolder/";
private static void createOutputFolder(String outputFolderName) {
File outputDirectory = new File(WORKSPACE + outputFolderName);
if (!outputDirectory.exists()) {
try {
outputDirectory.mkdir();
} catch (Exception e) {
}
}
}
private static void exlCreator() {
String outputFolder = "output/";
String fileName, fileNameWPathInput;
int serialNumber = 1;
createOutputFolder(outputFolder);
MaxDuplicateWordCount mdc = new MaxDuplicateWordCount();
File folder = new File(WORKSPACE);
File[] listOfFiles = folder.listFiles();
for (int i = 0; i < listOfFiles.length; i++) {
if (listOfFiles[i].isFile()) {
fileName = listOfFiles[i].getName();
fileNameWPathInput = WORKSPACE + fileName;
Map<String, Integer> wordMap = mdc.getWordCount(fileNameWPathInput);
List<Entry<String, Integer>> list = mdc.sortByValue(wordMap);
String fileNameWPathOutput = WORKSPACE + outputFolder +
fileName.substring(0, fileName.length() - 4)
+ "output.xls";
try {
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet("ResultSheet");
HSSFRow rowhead = sheet.createRow((short) 0);
rowhead.createCell(0).setCellValue("Serial No.");
rowhead.createCell(1).setCellValue("Word");
rowhead.createCell(2).setCellValue("Count");
for (Map.Entry<String, Integer> entry : list) {
HSSFRow row = sheet.createRow((short) serialNumber);
row.createCell(0).setCellValue(serialNumber);
row.createCell(1).setCellValue(entry.getKey());
row.createCell(2).setCellValue(entry.getValue());
serialNumber++;
}
FileOutputStream fileOut = new FileOutputStream(fileNameWPathOutput);
workbook.write(fileOut);
fileOut.close();
serialNumber = 1;
System.out.println(fileNameWPathOutput + " is created");
} catch (Exception ex) {
System.out.println(ex);
}
}
}
}
public static void main(String [] args) throws IOException {
exlCreator();
}
终于
通过操作代码,可以创建一个输出文件,但在工作表中创建每个输出结果。
如下图所示,输出文件在 Excel 中打开,显示 Unicode 文本没有问题,因为这是我的第一个解决方案中的问题:
链接
Download POI
POI documentation
Unicode problem in CSV
More about CSV
完整代码,从 OP 请求
import java.io.*;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.Map.Entry;
//for Excel ark
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFRow;
public class MaxDuplicateWordCount {
public Map<String, Integer> getWordCount(String fileName) {
FileInputStream fis = null;
DataInputStream dis = null;
BufferedReader br = null;
Map<String, Integer> wordMap = new HashMap<String, Integer>();
try {
fis = new FileInputStream(fileName);
dis = new DataInputStream(fis);
br = new BufferedReader(new InputStreamReader(dis));
String line = null;
while ((line = br.readLine()) != null) {
StringTokenizer st = new StringTokenizer(line, " ");
while (st.hasMoreTokens()) {
String tmp = st.nextToken().toLowerCase();
if (wordMap.containsKey(tmp)) {
wordMap.put(tmp, wordMap.get(tmp) + 1);
} else {
wordMap.put(tmp, 1);
}
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (br != null) br.close();
} catch (Exception ex) {
}
}
return wordMap;
}
public List<Entry<String, Integer>> sortByValue(Map<String, Integer> wordMap) {
Set<Entry<String, Integer>> set = wordMap.entrySet();
List<Entry<String, Integer>> list = new ArrayList<Entry<String, Integer>>(set);
Collections.sort(list, new Comparator<Map.Entry<String, Integer>>() {
public int compare(Map.Entry<String, Integer> o1, Map.Entry<String, Integer> o2) {
return (o2.getValue()).compareTo(o1.getValue());
}
});
return list;
}
final static String WORKSPACE = "C:/testfolder/";
private static void createOutputFolder(String outputFolderName) {
File outputDirectory = new File(WORKSPACE + outputFolderName);
if (!outputDirectory.exists()) {
try {
outputDirectory.mkdir();
} catch (Exception e) {
}
}
}
private static void exlCreator() {
String outputFolder = "output/";
String fileName, fileNameWPathInput;
int serialNumber = 1;
createOutputFolder(outputFolder);
MaxDuplicateWordCount mdc = new MaxDuplicateWordCount();
File folder = new File(WORKSPACE);
File[] listOfFiles = folder.listFiles();
for (int i = 0; i < listOfFiles.length; i++) {
if (listOfFiles[i].isFile()) {
fileName = listOfFiles[i].getName();
fileNameWPathInput = WORKSPACE + fileName;
Map<String, Integer> wordMap = mdc.getWordCount(fileNameWPathInput);
List<Entry<String, Integer>> list = mdc.sortByValue(wordMap);
String fileNameWPathOutput = WORKSPACE + outputFolder +
fileName.substring(0, fileName.length() - 4)
+ "output.xls";
try {
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet("ResultSheet");
HSSFRow rowhead = sheet.createRow((short) 0);
rowhead.createCell(0).setCellValue("Serial No.");
rowhead.createCell(1).setCellValue("Word");
rowhead.createCell(2).setCellValue("Count");
for (Map.Entry<String, Integer> entry : list) {
HSSFRow row = sheet.createRow((short) serialNumber);
row.createCell(0).setCellValue(serialNumber);
row.createCell(1).setCellValue(entry.getKey());
row.createCell(2).setCellValue(entry.getValue());
serialNumber++;
}
FileOutputStream fileOut = new FileOutputStream(fileNameWPathOutput);
workbook.write(fileOut);
fileOut.close();
serialNumber = 1;
System.out.println(fileNameWPathOutput + " is created");
} catch (Exception ex) {
System.out.println(ex);
}
}
}
}
public static void main(String[] args) throws IOException {
exlCreator();
}
}