java实现查找文本内容替换功能示例

思路:

先看视图层,要有一个JButton控件用来选择文件,一个JTextField控件显示选中文件的绝对路径,一个JLabel控件提示用户输入搜索文本,一个JLabel控件提示用户输入替换后的文本,一个JTextField标签供用户输入要搜索的文本,一个JTextField标签供用户输入替换后的文本,一个JButton控件执行替换,一个JButton控件用来打开修改后的文件。对于选择文件按钮,使用JButton类的addActionListener()方法为其绑定事件,在该事件中定义actionPerformed()函数,在该函数体中调用选择文件的方法。在选择文件方法中,首先创建JFileChooser文件选择器,使用JFileChooser类的setFileFilter()方法创建文件扩展名过滤器,再使用JFileChooser类的setFileSelectionMode()方法设置文件选择模式为文件,通过JFileChooser类的showOpenDialog()方法显示文件打开对话框,确定用户按下打开按钮,而非取消按钮后,通过JFileChooser类的getSelectedFile()方法获取用户选择的文件对象,使用JTextField类的setText()方法显示文件信息到文本框。对于替换按钮,同选择文件按钮,使用JButton类的addActionListener()方法为其绑定事件,在该事件中定义actionPerformed()函数,在该函数体中调用替换文本的方法。在替换文本方法中,首先使用TextField类的getText()方法获取要搜索的文本和要替换成的文本,若搜索文本不为空则尝试创建FileReader文件输入流和char缓冲字符数组以及StringBuilder字符串构建器,在while()循环中使用FileReader类的read()方法读取文件内容到字符串构建器,读取完毕后使用FileReader类的close()方法关闭输入流,使用StringBuilder类的replace()方法从构建器中生成字符串,并替换搜索文本,然后创建FileWriter文件输出流,使用FileWriter类的write()方法把替换完成的字符串写入文件内,然后使用FileWriter类的close()方法关闭输出流,然后依次捕获FileNotFoundException异常和IOException异常,最后使用JOptionPane类的showMessageDialog()方法提示用户替换完成。对于打开文件按钮,使用JButton类的addActionListener()方法为其绑定事件,在该事件中定义actionPerformed()函数,在该函数体中调用打开文件的方法。在打开文件方法中尝试使用 Desktop.getDesktop().edit(file);,并捕获IOException异常。代码如下:

代码如下:
import java.awt.BorderLayout;public class ReplaceFileText extends JFrame {    /**     *      */    private static final long serialVersionUID = 8674569541853793419L;    private JPanel contentPane;    private JTextField fileField;    private JTextField searchTextField;    private JTextField replaceTextField;    private File file;    /**     * Launch the application.     */    public static void main(String[] args) {        EventQueue.invokeLater(new Runnable() {            public void run() {                try {                    ReplaceFileText frame = new ReplaceFileText();                    frame.setVisible(true);                } catch (Exception e) {                    e.printStackTrace();                }            }        });    }    /**     * Create the frame.     */    public ReplaceFileText() {        setResizable(false);        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        setBounds(100, 100, 501, 184);        contentPane = new JPanel();        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));        contentPane.setLayout(new BorderLayout(0, 0));        setContentPane(contentPane);        JPanel panel = new JPanel();        panel.setPreferredSize(new Dimension(10, 91));        contentPane.add(panel, BorderLayout.CENTER);        GridBagLayout gbl_panel = new GridBagLayout();        gbl_panel.columnWidths = new int[] { 81, 0, 0, 66, 0 };        gbl_panel.rowHeights = new int[] { 23, 0, 0, 0, 0 };        gbl_panel.columnWeights = new double[] { 0.0, 0.0, 0.0, 1.0,                Double.MIN_VALUE };        gbl_panel.rowWeights = new double[] { 0.0, 0.0, 0.0, 0.0,                Double.MIN_VALUE };        panel.setLayout(gbl_panel);        JButton button = new JButton("选择文件");        button.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                do_button_actionPerformed(e);            }        });        GridBagConstraints gbc_button = new GridBagConstraints();        gbc_button.anchor = GridBagConstraints.NORTHWEST;        gbc_button.insets = new Insets(0, 0, 5, 5);        gbc_button.gridx = 0;        gbc_button.gridy = 0;        panel.add(button, gbc_button);        fileField = new JTextField();        fileField.setEditable(false);        GridBagConstraints gbc_fileField = new GridBagConstraints();        gbc_fileField.gridwidth = 3;        gbc_fileField.insets = new Insets(0, 0, 5, 0);        gbc_fileField.fill = GridBagConstraints.HORIZONTAL;        gbc_fileField.gridx = 1;        gbc_fileField.gridy = 0;        panel.add(fileField, gbc_fileField);        fileField.setColumns(10);        JLabel label = new JLabel("搜索文本:");        GridBagConstraints gbc_label = new GridBagConstraints();        gbc_label.anchor = GridBagConstraints.EAST;        gbc_label.insets = new Insets(0, 0, 5, 5);        gbc_label.gridx = 0;        gbc_label.gridy = 1;        panel.add(label, gbc_label);        searchTextField = new JTextField();        GridBagConstraints gbc_searchTextField = new GridBagConstraints();        gbc_searchTextField.gridwidth = 3;        gbc_searchTextField.insets = new Insets(0, 0, 5, 0);        gbc_searchTextField.fill = GridBagConstraints.HORIZONTAL;        gbc_searchTextField.gridx = 1;        gbc_searchTextField.gridy = 1;        panel.add(searchTextField, gbc_searchTextField);        searchTextField.setColumns(10);        JLabel label_1 = new JLabel("替换为:");        GridBagConstraints gbc_label_1 = new GridBagConstraints();        gbc_label_1.anchor = GridBagConstraints.EAST;        gbc_label_1.insets = new Insets(0, 0, 5, 5);        gbc_label_1.gridx = 0;        gbc_label_1.gridy = 2;        panel.add(label_1, gbc_label_1);        replaceTextField = new JTextField();        GridBagConstraints gbc_replaceTextField = new GridBagConstraints();        gbc_replaceTextField.gridwidth = 3;        gbc_replaceTextField.insets = new Insets(0, 0, 5, 0);        gbc_replaceTextField.fill = GridBagConstraints.HORIZONTAL;        gbc_replaceTextField.gridx = 1;        gbc_replaceTextField.gridy = 2;        panel.add(replaceTextField, gbc_replaceTextField);        replaceTextField.setColumns(10);        JPanel panel_1 = new JPanel();        GridBagConstraints gbc_panel_1 = new GridBagConstraints();        gbc_panel_1.gridwidth = 4;        gbc_panel_1.fill = GridBagConstraints.BOTH;        gbc_panel_1.gridx = 0;        gbc_panel_1.gridy = 3;        panel.add(panel_1, gbc_panel_1);        JButton replaceButton = new JButton("替换");        replaceButton.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                do_replaceButton_actionPerformed(e);            }        });        panel_1.add(replaceButton);        JButton openfileButton = new JButton("打开文件");        openfileButton.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                do_button_2_actionPerformed(e);            }        });        panel_1.add(openfileButton);    }    /**     * 选择文件按钮事件处理方法     *      * @param e     */    protected void do_button_actionPerformed(ActionEvent e) {        JFileChooser chooser = new JFileChooser("./");// 创建文件选择器        // 设置文件扩展名过滤器        chooser.setFileFilter(new FileNameExtensionFilter("文本文件", "txt",                "java", "php", "html", "htm"));        // 设置文件选择模式        chooser.setFileSelectionMode(JFileChooser.FILES_ONLY);        // 显示文件打开对话框        int option = chooser.showOpenDialog(this);        // 确定用户按下打开按钮,而非取消按钮        if (option != JFileChooser.APPROVE_OPTION)            return;        // 获取用户选择的文件对象        file = chooser.getSelectedFile();        // 显示文件信息到文本框        fileField.setText(file.toString());    }    /**     * 替换按钮的事件处理方法     *      * @param e     */    protected void do_replaceButton_actionPerformed(ActionEvent event) {        String searchText = searchTextField.getText();// 获取搜索文本        String replaceText = replaceTextField.getText();// 获取替换文本        if (searchText.isEmpty())            return;        try {            FileReader fis = new FileReader(file);// 创建文件输入流            char[] data = new char[1024];// 创建缓冲字符数组            int rn = 0;            StringBuilder sb = new StringBuilder();// 创建字符串构建器            while ((rn = fis.read(data)) > 0) {// 读取文件内容到字符串构建器                String str = String.valueOf(data, 0, rn);                sb.append(str);            }            fis.close();// 关闭输入流            // 从构建器中生成字符串,并替换搜索文本            String str = sb.toString().replace(searchText, replaceText);            FileWriter fout = new FileWriter(file);// 创建文件输出流            fout.write(str.toCharArray());// 把替换完成的字符串写入文件内            fout.close();// 关闭输出流        } catch (FileNotFoundException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }        JOptionPane.showMessageDialog(null, "替换完成");    }    /**     * 打开文件按钮的事件处理方法。     *      * @param e     */    protected void do_button_2_actionPerformed(ActionEvent e) {        try {            if (file == null)                return;            Desktop.getDesktop().edit(file);        } catch (IOException e1) {            e1.printStackTrace();        }    }}

以上是 java实现查找文本内容替换功能示例 的全部内容, 来源链接: utcz.com/p/207441.html

回到顶部