package com.winit.fna.excel;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Writer;
import java.util.Calendar;
import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import java.util.zip.ZipOutputStream;
import org.apache.poi.ss.usermodel.DateUtil;
import org.apache.poi.ss.util.CellReference;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
/**
* 抽象excel2007读入器，先构建.xlsx一张模板，改写模板中的sheet.xml,使用这种方法
* 写入.xlsx文件，不需要太大的内存
*
*/
public abstract class AbstractExcel2007Writer {
private SpreadsheetWriter sw;
/**
* 写入电子表格的主要流程
* @param fileName
* @throws Exception
*/
@SuppressWarnings("resource")
public void process(String fileName) throws Exception{
// 建立工作簿和电子表格对象
XSSFWorkbook wb = new XSSFWorkbook();
XSSFSheet sheet = wb.createSheet();
// 持有电子表格数据的xml文件名 例如 /xl/worksheets/sheet1.xml
String sheetRef = sheet.getPackagePart().getPartName().getName();
// 保存模板
FileOutputStream os = new FileOutputStream("D:\\template.xlsx");
wb.write(os);
os.close();
// 生成xml文件
File file = new File("D:\\");
File tmp = File.createTempFile("sheet", ".xml",file);
Writer fw = new FileWriter(tmp);
sw = new SpreadsheetWriter(fw);
generate();
fw.close();
// 使用产生的数据替换模板
File templateFile = new File("D:\\template.xlsx");
FileOutputStream out = new FileOutputStream(fileName);
substitute(templateFile, tmp, sheetRef.substring(1), out);
out.close();
//删除文件之前调用一下垃圾回收器，否则无法删除模板文件
System.gc();
// 删除临时模板文件
tmp.delete();
templateFile.delete();
}
/**
* 类使用者应该使用此方法进行写操作
* @throws Exception
*/
public abstract void generate() throws Exception;
public void beginSheet() throws IOException {
sw.beginSheet();
}
public void insertRow(int rowNum) throws IOException {
sw.insertRow(rowNum);
}
public void createCell(int columnIndex, String value) throws IOException {
sw.createCell(columnIndex, value, -1);
}
public void createCell(int columnIndex, double value) throws IOException {
sw.createCell(columnIndex, value, -1);
}
public void endRow() throws IOException {
sw.endRow();
}
public void endSheet() throws IOException {
sw.endSheet();
}
/**
*
* @param zipfile the template file
* @param tmpfile the XML file with the sheet data
* @param entry the name of the sheet entry to substitute, e.g. xl/worksheets/sheet1.xml
* @param out the stream to write the result to
*/
private static void substitute(File zipfile, File tmpfile, String entry,
OutputStream out) throws IOException {
ZipFile zip = new ZipFile(zipfile);
ZipOutputStream zos = new ZipOutputStream(out);
@SuppressWarnings("unchecked")
Enumeration<ZipEntry> en = (Enumeration<ZipEntry>) zip.entries();
while (en.hasMoreElements()) {
ZipEntry ze = en.nextElement();
if (!ze.getName().equals(entry)) {
zos.putNextEntry(new ZipEntry(ze.getName()));
InputStream is = zip.getInputStream(ze);
copyStream(is, zos);
is.close();
}
}
zos.putNextEntry(new ZipEntry(entry));
InputStream is = new FileInputStream(tmpfile);
copyStream(is, zos);
is.close();
zos.close();
}
private static void copyStream(InputStream in, OutputStream out)
throws IOException {
byte[] chunk = new byte[1024];
int count;
while ((count = in.read(chunk)) >= 0) {
out.write(chunk, 0, count);
}
}
/**
* 在写入器中写入电子表格
*
*/
public static class SpreadsheetWriter {
private final Writer _out;
private int _rownum;
private static String LINE_SEPARATOR = System.getProperty("line.separator");
public SpreadsheetWriter(Writer out) {
_out = out;
}
public void beginSheet() throws IOException {
_out.write("<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
+ "<worksheet xmlns=\"http://schemas.openxmlformats.org/spreadsheetml/2006/main\">");
_out.write("<sheetData>"+LINE_SEPARATOR);
}
public void endSheet() throws IOException {
_out.write("</sheetData>");
_out.write("</worksheet>");
}
/**
* 插入新行
*
* @param rownum 以0开始
*/
public void insertRow(int rownum) throws IOException {
_out.write("<row r=\"" + (rownum + 1) + "\">"+LINE_SEPARATOR);
this._rownum = rownum;
}
/**
* 插入行结束标志
*/
public void endRow() throws IOException {
_out.write("</row>"+LINE_SEPARATOR);
}
/**
* 插入新列
* @param columnIndex
* @param value
* @param styleIndex
* @throws IOException
*/
public void createCell(int columnIndex, String value, int styleIndex)
throws IOException {
String ref = new CellReference(_rownum, columnIndex)
.formatAsString();
_out.write("<c r=\"" + ref + "\" t=\"inlineStr\"");
if (styleIndex != -1)
_out.write(" s=\"" + styleIndex + "\"");
_out.write(">");
_out.write("<is><t>"+XMLEncoder.encode(value)+"</t></is>");
_out.write("</c>");
}
public void createCell(int columnIndex, String value)
throws IOException {
createCell(columnIndex, value, -1);
}
public void createCell(int columnIndex, double value, int styleIndex)
throws IOException {
String ref = new CellReference(_rownum, columnIndex)
.formatAsString();
_out.write("<c r=\"" + ref + "\" t=\"n\"");
if (styleIndex != -1)
_out.write(" s=\"" + styleIndex + "\"");
_out.write(">");
_out.write("<v>" + value + "</v>");
_out.write("</c>");
}
public void createCell(int columnIndex, double value)
throws IOException {
createCell(columnIndex, value, -1);
}
public void createCell(int columnIndex, Calendar value, int styleIndex)
throws IOException {
createCell(columnIndex, DateUtil.getExcelDate(value, false),
styleIndex);
}
}
}
