Question

JAVA怎么做点击按钮促发事件弹出浏览窗口选择excel文件读取,并显示到另外一个界面上，请给出主要代码

请简单粗暴的只给出代码和简要注释就好啊！！！

Answer 1

package com.excel;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;

import javax.swing.JTextArea;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;

/**
* 解析Excel的类
*/
public class ExcelOperate {
private JTextArea area;
private String fileName;

/**
* 构造方法传值
*
* @param area
* 显示Excel内容的位置
* @param fileName
* Excel文件名
*/
public ExcelOperate(JTextArea area, String fileName) {
this.area = area;
this.fileName = fileName;
}

/**
* 解析Excel文件
*/
public void parseExcel() {
File file = new File(fileName);
String[][] result = null;
try {
result = getData(file, 1);
} catch (IOException e) {
e.printStackTrace();
}
int rowLength = result.length;
for (int i = 0; i < rowLength; i++) {
for (int j = 0; j < result[i].length; j++) {
area.append(result[i][j] + "\t\t");
}
area.append("\n");
}

}

/**
* 读取Excel的内容，第一维数组存储的是一行中格列的值，二维数组存储的是多少个行
*
* @param file
* 读取数据的源Excel
* @param ignoreRows
* 读取数据忽略的行数，比喻行头不需要读入 忽略的行数为1
* @return 读出的Excel中数据的内容
* @throws FileNotFoundException
* @throws IOException
*/
public static String[][] getData(File file, int ignoreRows)
throws FileNotFoundException, IOException {
List<String[]> result = new ArrayList<String[]>();
int rowSize = 0;
BufferedInputStream in = new BufferedInputStream(new FileInputStream(
file));
// 打开HSSFWorkbook
POIFSFileSystem fs = new POIFSFileSystem(in);
HSSFWorkbook wb = new HSSFWorkbook(fs);
HSSFCell cell = null;
for (int sheetIndex = 0; sheetIndex < wb.getNumberOfSheets(); sheetIndex++) {
HSSFSheet st = wb.getSheetAt(sheetIndex);
// 第一行为标题，不取
for (int rowIndex = ignoreRows; rowIndex <= st.getLastRowNum(); rowIndex++) {
HSSFRow row = st.getRow(rowIndex);
if (row == null) {
continue;
}
int tempRowSize = row.getLastCellNum() + 1;
if (tempRowSize > rowSize) {
rowSize = tempRowSize;
}
String[] values = new String[rowSize];
Arrays.fill(values, "");
boolean hasValue = false;
for (short columnIndex = 0; columnIndex <= row.getLastCellNum(); columnIndex++) {
String value = "";
cell = row.getCell(columnIndex);
if (cell != null) {
switch (cell.getCellType()) {
case HSSFCell.CELL_TYPE_STRING:
value = cell.getStringCellValue();
break;
case HSSFCell.CELL_TYPE_NUMERIC:
if (HSSFDateUtil.isCellDateFormatted(cell)) {
Date date = cell.getDateCellValue();
if (date != null) {
value = new SimpleDateFormat("yyyy-MM-dd")
.format(date);
} else {
value = "";
}
} else {
value = new DecimalFormat("0").format(cell
.getNumericCellValue());
}
break;
case HSSFCell.CELL_TYPE_FORMULA:
// 导入时如果为公式生成的数据则无值
if (!cell.getStringCellValue().equals("")) {
value = cell.getStringCellValue();
} else {
value = cell.getNumericCellValue() + "";
}
break;
case HSSFCell.CELL_TYPE_BLANK:
break;
case HSSFCell.CELL_TYPE_ERROR:
value = "";
break;
case HSSFCell.CELL_TYPE_BOOLEAN:
value = (cell.getBooleanCellValue() == true ? "Y"
: "N");
break;
default:
value = "";
}
}
if (columnIndex == 0 && value.trim().equals("")) {
break;
}
values[columnIndex] = rightTrim(value);
hasValue = true;
}

if (hasValue) {
result.add(values);
}
}
}
in.close();
String[][] returnArray = new String[result.size()][rowSize];
for (int i = 0; i < returnArray.length; i++) {
returnArray[i] = (String[]) result.get(i);
}
return returnArray;
}

/**
* 去掉字符串右边的空格
*
* @param str
* 要处理的字符串
* @return 处理后的字符串
*/
public static String rightTrim(String str) {
if (str == null) {
return "";
}
int length = str.length();
for (int i = length - 1; i >= 0; i--) {
if (str.charAt(i) != 0x20) {
break;
}
length--;
}
return str.substring(0, length);
}
}
------------------------------------------------------------------------------------------
package com.excel;

import java.awt.BorderLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.filechooser.FileNameExtensionFilter;

/**
* 主界面，按钮响应事件，文本域输出Excel内容
*/
public class OpenExcel extends JFrame implements ActionListener {
private JButton button;
private JScrollPane pane;
private JTextArea area;

public OpenExcel() {
super("解析Excel");

button = new JButton("点我选择Excel文件");
button.addActionListener(this);

area = new JTextArea();
pane = new JScrollPane(area);

this.add(button, BorderLayout.NORTH);
this.add(pane);
this.setSize(300, 300);
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
}

// 按钮事件
public void actionPerformed(ActionEvent e) {
JFileChooser chooser = new JFileChooser();// 文件选择对话框
chooser.setAcceptAllFileFilterUsed(false);// 取消所有文件过滤项
chooser.setFileFilter(new FileNameExtensionFilter("Excel文件", "xls"));// 设置只过滤扩展名为.xls的Excel文件

int i = chooser.showOpenDialog(this);// 打开窗口
if (i == JFileChooser.APPROVE_OPTION) {
this.setLocation(0, 0);
this.setSize(Toolkit.getDefaultToolkit().getScreenSize());
new ExcelOperate(area, chooser.getSelectedFile().getAbsolutePath())
.parseExcel();
}
}

public static void main(String[] args) throws Exception {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
new OpenExcel();
}
}

追问

请问这个地方报错应该怎么修改？？？

追答

到阿帕奇官网下载解析Excel的jar包，这个链接----->http://apache.fayea.com/poi/release/bin/poi-bin-3.12-20150511.zip

追问

把这个下载之后应该解压到哪里然后怎么用？？？比较笨。。。麻烦你了。。。不好意思啊！

追答

图片所示，不懂再追问

追问

那个弄好了买这个又开始报错了。。。这个之前是没有问题的，不知道为什么忽然就显示了一堆错误！！！留个私信来联系吧？？？谢谢啦！！！