我如何在java中实际使用delimeter，这是示例data.dat文件
1 yuri
2 fisher
3 McMillan
4 price
5 soap
我怎样才能获取文件中每行中的第一个数字并使用useDelimiter（）方法
我该怎么做到这个代码
Scanner src = new Scanner(fin);
src.useDelimiter(" \n");
DefaultListModel model = new DefaultListModel();
while (src.hasNext()) {
String lol = src.nextLine();
model.addElement(lol);
}
list.setModel(model);
}
});
这是整个代码..嗯..文件中并不总是'lol'我稍后会改变它
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.Scanner;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.DefaultListModel;
import javax.swing.DefaultListSelectionModel;
import javax.swing.ListSelectionModel;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
/**
*
* @author Jfetizanan
*/
@SuppressWarnings("serial")
public class IOtestForm extends javax.swing.JFrame {
/**
* Creates new form IOtest
*/
public IOtestForm() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jScrollPane1 = new javax.swing.JScrollPane();
list = new javax.swing.JList();
input0 = new javax.swing.JTextField();
load = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jScrollPane1.setViewportView(list);
DefaultListSelectionModel m = new DefaultListSelectionModel();
m.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
m.setLeadAnchorNotificationEnabled(false);
list.setSelectionModel(m);
list.addListSelectionListener(new ListSelectionListener() {
@Override
public void valueChanged(ListSelectionEvent e) {
int selected[] = list.getSelectedIndices();
for (int i = 0; i < selected.length; i++) {
String element = (String) list.getModel().getElementAt(selected[i]);
input0.setText(element);
}}});
load.setText("Load");
load.addActionListener(new ActionListener() {
@Override
@SuppressWarnings("unchecked")
public void actionPerformed(ActionEvent e) {
FileReader fin = null;
try {
fin = new FileReader("data.dat");
} catch (FileNotFoundException ex) {
Logger.getLogger(IOtestForm.class.getName()).log(Level.SEVERE, null, ex);
}
Scanner src = new Scanner(fin);
src.useDelimiter("\\s*lol\\s*");
DefaultListModel model = new DefaultListModel();
while (src.hasNext()) {
String lol = src.next();
model.addElement(lol);
}
list.setModel(model);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 380, Short.MAX_VALUE)
.addComponent(input0)
.addComponent(load, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(13, 13, 13)
.addComponent(load)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(input0, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(94, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
/**
* @param args the command line arguments
*/
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 | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(IOtestForm.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new IOtestForm().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JTextField input0;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JList list;
private javax.swing.JButton load;
// End of variables declaration
}
答案 0 :(得分：2)
您可以使用src.useDelimiter("\\s*lol\\s*")。有关解析的示例，请参阅http://ideone.com/kZUL6。
答案 1 :(得分：1)
另一种解决方案是将每一行拆分为空格：
String[] split = lol.trim().split("\\s+");
然后你应该看到每个split[0]的第一个数字。
答案 2 :(得分：1)
让我们从基本的
开始要加载文件，您可以执行此操作
Scanner src = new Scanner(is);
while (src.hasNext()) {
int line = src.nextInt();
String value = src.next();
System.out.println(line + " = " + value);
}
现在，我们真正需要的是一些模拟这些信息的方法。更好的解决方案是创建一种代表此信息的Object，使其更易于管理。
像
这样的东西public class LineOfText {
private int line;
private String value;
public LineOfText(int line, String value) {
this.line = line;
this.value = value;
}
public int getLine() {
return line;
}
public String getValue() {
return value;
}
}
好的，那么我们需要将文件中的属性应用到它。
Scanner src = new Scanner(is);
while (src.hasNext()) {
int line = src.nextInt();
String value = src.next();
LineOfText lot = new LineOfText(line, value);
}
我们可以添加到您已创建的ListModel。
model.addElement(lot);
现在，如果我们在UI上显示它，它看起来不太漂亮。我们真正需要的是一些更有效地“渲染”文本的方法。
像
这样的东西public class LineOfTextListCellRenderer extends DefaultListCellRenderer {
@Override
public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
if (value instanceof LineOfText) {
value = ((LineOfText)value).getLine();
}
return super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
}
}
应该这样做。我们需要将此渲染器应用于您之前创建的列表。
list.setListCellRenderer(new LineOfTextListCellRenderer());
现在，如果我们在UI上显示这个，我们应该只看到列表中的行号。
接下来，我们需要一些方法来检测选择的变化。为此，我们需要ListSelectionListener
list.addListSelectionListener(new ListSelectionListener() {
@Override
public void valueChanged(ListSelectionEvent e) {
Object item = list.getSelectedItem();
if (item != null && item instance of LineOfText) {
ListOfText lot = (LineOfText)lot;
// Now we have access to the text value
// Simply use "setText" on the text area to apply it
textArea.setText(lot.getValue());
// Remember, "textArea" should be replaced with the name
// of your text area
}
}
});
现在你明白为什么这是一个单独的问题;）
答案 3 :(得分：1)
将分隔符设置为\\s*lol\\s*
public static void main(String[] args)
{
String myString = "1 lol\n2 lol\n3 lol\n4 lol\n5 lol";
System.out.println(myString);
Scanner scanner = new Scanner(myString);
scanner = scanner.useDelimiter("\\s*lol\\s*");
while(scanner.hasNext())
{
System.out.println(scanner.next());
}
}