输出结果 shop.addBooks(); //购物车中加东西 HashMap book4=(HashMap)shop.getBook3(); shop.getSum(book4); //购物车算总价 } } 《JAVA程序设计》实验报告8
姓名 杨仕琴 学号 54121022 日期 10.13 实验题目 package unit8; 程序初稿 import java.awt.*; import java.awt.event.*; import javax.swing.*; import java.io.*; public class ddd extends JFrame implements ActionListener { JTextArea txtMessage; JButton btnRead, btnWrite; public ddd() { super(\文本读写\txtMessage = new JTextArea(15, 30); btnRead = new JButton(\读取\btnWrite = new JButton(\写入\this.setLayout(new FlowLayout()); this.add(new JLabel(\文件内容：\this.add(txtMessage); this.add(btnRead); this.add(btnWrite); btnRead.addActionListener(this); btnWrite.addActionListener(this); this.setSize(400, 400); this.setVisible(true); this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); } public static void main(String[] args) { new ddd(); } public void actionPerformed(ActionEvent e) { JButton btn = (JButton)e.getSource(); String fileName = \if(btn.getText().equals(\读取\try{ InputStream is = new FileInputStream(fileName); BufferedReader br = new BufferedReader(new InputStreamReader(is)); String line = null; StringBuffer buffer = new StringBuffer(); while((line = br.readLine()) != null){ buffer.append(line + \} txtMessage.setText(buffer.toString()); br.close(); is.close(); } else if(btn.getText().equals(\写入\try{ String msg = txtMessage.getText(); OutputStream os = new FileOutputStream(fileName); PrintStream ps = new PrintStream(os); ps.print(msg); ps.close(); os.close(); } } } } 所遇问题 及 文件读写的类太多，查API查很久 解决办法 package unit8; 调试后的import java.awt.*; 程序代码 import java.awt.event.*; import javax.swing.*; import java.io.*; public class ddd extends JFrame implements ActionListener { JTextArea txtMessage; JButton btnRead, btnWrite; public ddd() { super(\文本读写\txtMessage = new JTextArea(15, 30); btnRead = new JButton(\读取\btnWrite = new JButton(\写入\this.setLayout(new FlowLayout()); this.add(new JLabel(\文件内容：\this.add(txtMessage); this.add(btnRead); this.add(btnWrite); btnRead.addActionListener(this); btnWrite.addActionListener(this); this.setSize(400, 400); this.setVisible(true); this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); } public static void main(String[] args) { new ddd(); } @Override public void actionPerformed(ActionEvent e) { JButton btn = (JButton)e.getSource(); String fileName = \if(btn.getText().equals(\读取\try{ InputStream is = new FileInputStream(fileName); BufferedReader br = new BufferedReader(new InputStreamReader(is));