我正在尝试创建一个程序，将excel中的所有数据写入多个csv文件。
目前，我的程序创建了 n 个文件，并且只在最后一个csv文件中写入了最后一行excel。
好像文件正在写。但是对于每个写入的行，它以某种方式创建相同的文件250次。它会删除最后写入的行。
使用 OutputStream 或 BufferedWriter 时，我可能会遇到一些问题。我只是想不通它是什么。
writeRow（）方法：
public static void writeRow(BufferedWriter bw, Cell[] row) throws IOException {
if (row.length > 0) {
bw.write(row[0].getContents());
for (int j = 1; j < row.length; j++) {
bw.write(',');
bw.write(row[j].getContents());
}
}
}
setFile（）方法：
public static BufferedWriter setFile (int i) throws IOException {
i=i/250;
File f = new File(dir + "file-" + (i+1) + ".csv");
// If i has changed, create a new file. Else, append to current file.
String encoding = "UTF8";
OutputStream os = null;
OutputStreamWriter osw = null;
BufferedWriter bw = null;
Boolean append = null;
try {
// If i has changed, create a new file, else append.
if (i%250==0) {
append = new Boolean("TRUE");
os = new FileOutputStream(f,append);
} else {
append = new Boolean("FALSE");
os = new FileOutputStream(f, append);
}
osw = new OutputStreamWriter(os, encoding);
bw = new BufferedWriter(osw);
} finally {
os.close();
osw.close();
}
return bw;
}
以下是例外情况。
Exception in thread "main" java.io.IOException: Stream closed
at sun.nio.cs.StreamEncoder.ensureOpen(Unknown Source)
at sun.nio.cs.StreamEncoder.write(Unknown Source)
at java.io.OutputStreamWriter.write(Unknown Source)
at java.io.BufferedWriter.flushBuffer(Unknown Source)
at java.io.BufferedWriter.flush(Unknown Source)
at Main.main(Main.java:46)
以下是代码的一些链接。
我做错了什么？
这是svn trunk：
https://franz-opensource.googlecode.com/svn/trunk/ExcelToCsv -
答案 0 :(得分：0)
重要建议： 在每个 nth 记录之后停止行，而不是写在同一个缓冲区上。然后，阅读 工作表再次。然后，在另一个文件上输出缓冲区。在同一缓冲区上写入时，您无法更改文件。
以下是整个解决方案：
静态变量：
public static int maxRecords = 250;
public static String directory = "C:\\Users\\User02\\workspace\\ExcelToCsv\\src\\";
public static String inputFile = directory + "inventory.xls";
主要
public static void main(String[] args) throws BiffException, IOException {
Sheet s = getSheet();
int countRows = s.getRows(); // counts the number of rows in the sheet.
int numberOfFiles = (countRows/maxRecords)+1;
for(int file=0; file<numberOfFiles; file++) {
System.out.println("Create file number " + (file+1));
int fileNumber = file+1;
System.out.println("Start number: " + ((file*maxRecords)+1));
int startNumber = (file*maxRecords);
populateFile(fileNumber,startNumber);
System.out.println("");
}
}
填充列表：
public static void populateFile(int fileNumber, int startNumber)
throws IOException, BiffException {
BufferedWriter bw = setFile(fileNumber);
Sheet s = getSheet();
Cell[] row = null;
writeRow(bw,s.getRow(0));
bw.newLine();
int limit = getLimit(s,startNumber);
System.out.println("End Number:" + limit);
System.out.println();
for (int i = startNumber; i < limit ; i++) {
row = s.getRow(i);
//System.out.println(i);
writeRow(bw,row);
bw.newLine();
}
bw.flush();
bw.close();
}
获取工作表：
public static Sheet getSheet() throws BiffException, IOException {
WorkbookSettings ws = new WorkbookSettings();
ws.setLocale(new Locale("en", "EN"));
Workbook w = Workbook.getWorkbook(new File(inputFile),ws);
Sheet s = w.getSheet(0);
return s;
}
设置要写入的文件：
public static BufferedWriter setFile(int fileNumber) throws IOException {
String csvFilename = directory + "file-"+ fileNumber +".csv";
FileWriter csvFile = new FileWriter(csvFilename);
BufferedWriter bw = new BufferedWriter(csvFile);
return bw;
}
获得限制：
public static int getLimit(Sheet s, int startNumber) {
int limit;
int countRows = s.getRows();
if (startNumber+maxRecords<=countRows) {
limit = startNumber + maxRecords;
} else {
limit = startNumber + (countRows-startNumber);
}
return limit;
}
将行写入文件：
public static void writeRow(BufferedWriter bw, Cell[] row) throws IOException {
if (row.length > 0) {
bw.write(row[0].getContents());
for (int j = 1; j < row.length; j++) {
bw.write(',');
bw.write(row[j].getContents());
}
}
}