java实现极简单的 TXT小说阅读器

public class Display_txt extends JFrame {
	
	JFrame jframe = new JFrame();
	JTextArea content;
	boolean flag = true;
	String str_filePath = null;
	
	public Display_txt(){
		//输入框
		content = new JTextArea(10,50);
		content.setAutoscrolls(true);
		JScrollPane contentScroll = new JScrollPane(content);
		content.setBorder(BorderFactory.createBevelBorder(1));
		JPanel upper = new JPanel(new BorderLayout());
		upper.add(contentScroll);
		//按钮
		JButton filePath = new JButton("打开文件");
		filePath.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				try{
					JFileChooser jfc = new JFileChooser();
					if(jfc.showOpenDialog(jframe)==JFileChooser.APPROVE_OPTION ){
						str_filePath = jfc.getSelectedFile().getAbsolutePath();
					}
					BufferedReader bufferedReader = new BufferedReader(new FileReader(str_filePath));
					String str_line;
					while((str_line=bufferedReader.readLine())!=null){
						if(flag){
							content.setText(str_line);
							flag = false;
						}
						else{
							content.setText(content.getText()+"\n"+str_line);
						}
					}
					bufferedReader.close();
				}catch(FileNotFoundException e1){
					e1.printStackTrace();
				}catch(IOException e2){
					e2.printStackTrace();
				}
			}
		});
		JPanel buttonp = new JPanel();
		buttonp.add(filePath);
		JPanel all = new JPanel(new GridLayout(1,1));
		all.add(upper);
		jframe.add(buttonp,BorderLayout.SOUTH);
		jframe.add(all,BorderLayout.CENTER);
		jframe.pack();
		Toolkit tool = Toolkit.getDefaultToolkit();
		Dimension screen = tool.getScreenSize();
		jframe.setLocation(screen.width/2-jframe.getWidth()/2,screen.height/2-jframe.getHeight()/2);
		jframe.setTitle("TXT小说阅读器");
		jframe.setVisible(true);
		jframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}
	
	public static void main(String args[]){
		Display_txt display_demo = new Display_txt();
	}

}public class Display_txt extends JFrame {
	
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