问题描述
Text FileAfter Importing DataJTable with existing data 我尝试将 JTable 数据导出到文本文件并将数据导入回同一个 JTable。但是文本文件和 JTable 中的数据顺序不正确，如图所示。表格中的某些单元格填充了两个或多个单词。帮我解决问题是高度赞赏？提前致谢。
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFileChooser;
import javax.swing.JOptionPane;
import javax.swing.table.DefaultTableModel;
public class SaveTest1 extends javax.swing.JFrame{
public SaveTest1() {
initComponents();
setLocationRelativeto(null);
}
@SuppressWarnings("unchecked")
private void initComponents() {
java.awt.GridBagConstraints gridBagConstraints;
jFileChooser1 = new javax.swing.JFileChooser();
jScrollPane1 = new javax.swing.JScrollPane();
jTable1 = new javax.swing.JTable();
jButton1 = new javax.swing.JButton();
jButton2 = new javax.swing.JButton();
jButton3 = new javax.swing.JButton();
setDefaultCloSEOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
getContentPane().setLayout(new java.awt.GridBagLayout());
jTable1.setModel(new javax.swing.table.DefaultTableModel(
new Object [][] {
{"1","Engineering Brick","Nos","18.00","550","9900.00"},{"2","River Sand","Cube","15000.00","0.1","1500.00"},{"3","Cement","cwt","1100.00","3","3300.00"},{null,null,"Cost of Material","14700.00"}
},new String [] {
"ID","Name","Unit","Price","Qty","Amount"
}
) {
Class[] types = new Class [] {
java.lang.String.class,java.lang.String.class,java.lang.String.class
};
public Class getColumnClass(int columnIndex) {
return types [columnIndex];
}
});
jScrollPane1.setViewportView(jTable1);
gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 0;
gridBagConstraints.gridwidth = 2;
gridBagConstraints.fill = java.awt.GridBagConstraints.BOTH;
gridBagConstraints.weightx = 0.1;
gridBagConstraints.weighty = 0.1;
gridBagConstraints.insets = new java.awt.Insets(5,5,5);
getContentPane().add(jScrollPane1,gridBagConstraints);
jButton1.setText("Export");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 1;
gridBagConstraints.weightx = 0.1;
gridBagConstraints.insets = new java.awt.Insets(5,5);
getContentPane().add(jButton1,gridBagConstraints);
jButton2.setText("Import");
jButton2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton2ActionPerformed(evt);
}
});
gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.gridx = 1;
gridBagConstraints.gridy = 1;
gridBagConstraints.weightx = 0.1;
gridBagConstraints.insets = new java.awt.Insets(5,5);
getContentPane().add(jButton2,gridBagConstraints);
pack();
}
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
JFileChooser fileChooser = new JFileChooser();
fileChooser.setDialogTitle("Save as");
int userSelection = fileChooser.showSaveDialog(this);
if (userSelection == JFileChooser.APPROVE_OPTION) {
File filetoSave = fileChooser.getSelectedFile();
try {
FileWriter fw = new FileWriter(filetoSave);
BufferedWriter bw = new BufferedWriter(fw);
for (int i = 0; i < jTable1.getColumnCount(); i++) {
bw.write(jTable1.getColumnName(i));
bw.write("\t");
}
for (int i = 0; i < jTable1.getRowCount(); i++) {
bw.newLine();
for (int j = 0; j < jTable1.getColumnCount(); j++) {
bw.write((String) jTable1.getValueAt(i,j));
String val = (String) jTable1.getValueAt(i,j);
if (val == null) {
val = "";
}
bw.write("\t");
}
}
JOptionPane.showMessageDialog(this,"File Saved","information",JOptionPane.informatION_MESSAGE);
bw.close();
fw.close();
} catch (IOException ex) {
JOptionPane.showMessageDialog(this,"Error","Error Message",JOptionPane.ERROR_MESSAGE);
}
}
}
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
JFileChooser fileChooser = new JFileChooser();
fileChooser.setDialogTitle("Open");
int userSelection = fileChooser.showOpenDialog(this);
if (userSelection == JFileChooser.APPROVE_OPTION) {
File filetoOpen = fileChooser.getSelectedFile();
try {
FileReader fr = new FileReader(filetoOpen);
BufferedReader br = new BufferedReader(fr);
DefaultTableModel model1 = (DefaultTableModel) jTable1.getModel();
Object[] lines = br.lines().toArray();
for (int i = 1; i < lines.length; i++) {
String[] row = lines[i].toString().split(" ");
model1.addRow(row);
}
} catch (Exception ex) {
Logger.getLogger(SaveTest1.class.getName()).log(Level.SEVERE,ex);
}
}
}
private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {
DefaultTableModel model1 = (DefaultTableModel) jTable1.getModel();
model1.setRowCount(0);
}
public static void main(String args[]) {
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(SaveText.class.getName()).log(java.util.logging.Level.SEVERE,ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(SaveText.class.getName()).log(java.util.logging.Level.SEVERE,ex);
} catch (illegalaccessexception ex) {
java.util.logging.Logger.getLogger(SaveText.class.getName()).log(java.util.logging.Level.SEVERE,ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(SaveText.class.getName()).log(java.util.logging.Level.SEVERE,ex);
}
java.awt.EventQueue.invokelater(new Runnable() {
public void run() {
new SaveText().setVisible(true);
}
});
}
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JButton jButton3;
private javax.swing.JFileChooser jFileChooser1;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTable jTable1;
}
解决方法
写入文件时，您用制表符 bw.write("\t"); 分隔单元格，但读回数据时，您使用空格 String[] row = lines[i].toString().split(" "); 来标识每个单元格的边框。不要这样做。在写入和读回时使用相同的字符或字符串来分隔单元格。
考虑
String[] row = lines[i].split("\t",-1);
代替
此外，最好将 Stream 转换为 String-specific 数组而不是 Object 数组：
String[] lines = br.lines().toArray(String[]::new);