Question

我正在尝试从/向文件读取和写入条目，并且遇到了一些问题。正在创建文件，但它没有被写入，因此没有被读取。我将它设置为单击按钮时，它应该从文件中写入和读取并将内容显示到textarea中。这是我的代码：

public void actionPerformed(ActionEvent event) 
{
    if (event.getSource() == this.saveToFile) {
        // save to file
       try {
           if (Integer.parseInt(this.age.getText()) > 0 && Integer.parseInt(this.age.getText()) <= 120) {
               this.openFile();
               this.writeToFile();
           } else {
               JOptionPane.showMessageDialog(rootPane, "Age must be greater than zero and no more than 120");
           }
       } catch (IOException e) {
           // ignore
       }
    } else if (event.getSource() == this.exitProgram) {
        System.exit(0);
    } else if (event.getSource() == this.readFromFile) {
        // read from file
        this.openFile();
        this.readFile();
    }
}

private void openFile()
{
    try {
        this.scan = new Scanner(new File("contacts.txt"));
    } catch (Exception e) {
        // ignore
    }
}

private void writeToFile() throws IOException
{
     BufferedWriter outfile = new BufferedWriter(new FileWriter("contacts.txt"));

     outfile.write("Name: ");
     outfile.write(this.name.getText());

     outfile.write("Age: ");
     outfile.write(this.age.getText());

     outfile.write("Email: ");
     outfile.write(this.email.getText());

     outfile.write("Cell Phone: ");
     outfile.write(this.cell.getText());

     outfile.write("\n\n");
}

private void readFile()
{
    while (this.scan.hasNext()) {
        this.textArea.append(this.scan.next() + "\t");
    }
}

任何帮助将不胜感激。

谢谢！

Answer 1

尝试在writeToFile（）

的末尾添加

outfile.flush();
outfile.close();

flush将告诉操作系统将文件写入媒体，关闭将释放文件占用的资源。

Answer 2

BufferedReader执行缓冲输入。在writeToFile() - 方法的末尾，您应该使用outfile.flush();将缓冲区中的所有待处理数据写入文件。此外，完成后请关闭资源：outfile.close();。您可能需要查看try-with-resources

读/写文件Java

2 个答案: