}
}
void reader() {
String s1, s2 = \
s1 = jt1.getText().trim(); if (s1.equals(\
JOptionPane.showMessageDialog(null, \没有输入文件名\ jt1.requestFocus(); } else {
try {
FileInputStream file = new FileInputStream(s1); int c;
while ((c = file.read()) != -1) s2 = s2 + (char) c; jt2.setText(s2); file.close();
} catch (IOException ie) {
}
}
jt1.setText(\
}
public static void main(String args[]) { new readerbyte(); }
}
import java.io.*; import java.awt.*; import java.awt.event.*; import javax.swing.*;
public class readerbyte extends JFrame implements ActionListener { JButton b1, b2, b3;
JTextField jt1;
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JTextArea jt2; readerbyte() { setTitle(\演示\); getContentPane().setLayout(new FlowLayout()); this.setDefaultLookAndFeelDecorated(true); this.setSize(450, 350); b1 = new JButton(\写入\); b2 = new JButton(\读取\); b3 = new JButton(\退出\); b1.addActionListener(this); b2.addActionListener(this); b3.addActionListener(this); jt1 = new JTextField(10); jt2 = new JTextArea(10, 30); jt2.setLineWrap(true); jt2.setWrapStyleWord(true);
JScrollPane jspa = new JScrollPane(jt2); JPanel p1 = new JPanel();
p1.add(new JLabel(\请输入文件名：\)); p1.add(jt1);
JPanel p2 = new JPanel(); p2.add(new JLabel(\文件内容：\)); p2.add(jspa);
JPanel p3 = new JPanel(); p3.add(b1); p3.add(b2); p3.add(b3);
getContentPane().add(p1); getContentPane().add(p2); getContentPane().add(p3); setVisible(true);
}
public void actionPerformed(ActionEvent ee) { if (ee.getSource() == b3) { dispose(); System.exit(0);
}
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if (ee.getSource() == b1)
writer();
if (ee.getSource() == b2)
reader();
}
void writer() { String s1, s2;
s1 = jt1.getText().trim(); if (s1.equals(\)) { JOptionPane.showMessageDialog(null, \没有输入文件名\); jt1.requestFocus(); } else {
s2 = jt2.getText().trim(); char s22[] = s2.toCharArray(); try { FileWriter file = new FileWriter(s1); for (int i = 0; i < s22.length; i++)
file.write(s22[i]); file.close();
} catch (IOException ie) {
}
jt1.setText(\); jt2.setText(\);
}
}
void reader() { String s1, s2 = \; s1 = jt1.getText().trim(); if (s1.equals(\)) { JOptionPane.showMessageDialog(null, \没有输入文件名\);
jt1.requestFocus();
} else
{ try {
FileReader file = new FileReader(s1);
int c;
while ((c = file.read()) != -1)
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s2 = s2 + (char) c;
jt2.setText(s2); file.close();
} catch (IOException ie) {
}
}
jt1.setText(\);
}
public static void main(String args[]) { new readerbyte();
}
}
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