我的问题很简单。我试图将arrayList的最后一个元素添加到该数组列表的末尾,其行如:
ArrayList.add(ArrayList.get(ArrayList.size()));
但我得到的是indexOutOfBoundsException。
有没有办法在不登陆异常的情况下执行此操作?快速回答。该行不包含在任何循环中。 arrayList有大小。我已经尝试使用ArrayList.size() - 1无效,这里是它包含的完整代码块。
public class SaveButtonListener implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
JFileChooser fileChooser = new JFileChooser(".");
int status = fileChooser.showSaveDialog(null);
if (status == JFileChooser.APPROVE_OPTION) {
File selectedFile = fileChooser.getSelectedFile();
String fileName = selectedFile.getPath();
File imageFolder = new File(fileName);
imageFolder.mkdir();
//tokenizes the path into an arraylist
String delims = "/";
ArrayList<String> fileTokensList = new ArrayList<>();
String[] fileTokens = fileName.split(delims);
fileTokensList.addAll(Arrays.asList(fileTokens));
//adds the name of the current image
fileTokensList.add(fileTokensList.get(fileTokensList.size()));
//rebuilds all the tokens into one string path
StringBuilder builder = new StringBuilder();
for (int s = 0; s < fileTokensList.size(); s++) {
if (s == 0) {
builder.append(fileTokensList.get(s));
} else {
builder.append("/");
builder.append(fileTokensList.get(s));
}
}
String textFileName = builder.toString();
System.out.println(textFileName);
try {
File saveFile = new File(textFileName);
FileWriter fileWriter = new FileWriter(saveFile);
try (BufferedWriter bufferedWriter = new BufferedWriter(fileWriter)) {
for (int i = 0; i < Driver.vehicleList.size()+1; i++) {
//writes the text file (one entry per line
bufferedWriter.write(Driver.vehicleList.get(i).getPrice());
bufferedWriter.write("\t");
bufferedWriter.write(Driver.vehicleList.get(i).getYear());
bufferedWriter.write("\t");
bufferedWriter.write(Driver.vehicleList.get(i).getMake());
bufferedWriter.write("\t");
bufferedWriter.write(Driver.vehicleList.get(i).getModel());
bufferedWriter.write("\t");
bufferedWriter.write(Driver.vehicleList.get(i).getComments());
bufferedWriter.newLine();
//adds the name of the current image
fileTokensList.add(Integer.toString(i));
//rebuilds all the tokens into one string path
StringBuilder imagePathBuilder = new StringBuilder();
for (int s = 0; s < fileTokensList.size(); s++) {
if (s == 0) {
imagePathBuilder.append(fileTokensList.get(s));
} else {
imagePathBuilder.append("/");
imagePathBuilder.append(fileTokensList.get(s));
}
}
String imageFileName = builder.toString();
//resaves the picture to the same place
Path FROM = Paths.get(Driver.vehicleList.get(i).getCarPicture());
Path TO = Paths.get(imageFileName);
//overwrite existing file, if exists
CopyOption[] options = new CopyOption[]{
StandardCopyOption.REPLACE_EXISTING,
StandardCopyOption.COPY_ATTRIBUTES
};
Files.copy(FROM, TO, options);
}
}
} catch (IOException IO) {
System.out.println("Error writing to file");
}
JOptionPane.showMessageDialog(null, "All your information has been saved");
}
}
}
这段代码是为了将文件保存到某个位置,而且我做了很多乱码和重建该路径。我是否已经走了很长的路要走一个简单的解决方案,或者我做得对吗?
答案 0 :(得分:1)
ArrayList.get(int index)
值介于0和index
之间, Array.size() - 1
将有效。由于您要发送Array.size()
,因此您将转到数组的无效位置,从而获得异常。
如何解决这个问题?好吧,你应该发布你想要添加的内容,你会得到答案。
答案 1 :(得分:0)
ArrayList<String> fileTokensList = new ArrayList<>();
您的列表包含字符串,因此您需要获取列表的大小并将其转换为字符串,然后再将其添加到列表中。
list.add( list.size() + "")
执行此操作的一种方法是使用“+”连接运算符,编译器将自动为您创建字符串。
答案 2 :(得分:0)
尝试更改:
ArrayList.add(ArrayList.get(ArrayList.size()));
到
ArrayList.add(ArrayList.get(ArrayList.size()-1));