Java 如何检查用户输入路径是否正确?
我需要证明用户输入路径。Java 如何检查用户输入路径是否正确?,java,validation,user-input,Java,Validation,User Input,我需要证明用户输入路径。 因为用户提供的不是文件夹路径而是文件路径。程序“下降”。 我知道这是一个bug,但如何确保用户路径正确 代码: class PathAndWord { final String path; final String whatFind; PathAndWord(String path, String whatFind) { this.path = path; this.whatFind = whatFind;
因为用户提供的不是文件夹路径而是文件路径。程序“下降”。
我知道这是一个bug,但如何确保用户路径正确 代码:
class PathAndWord {
final String path;
final String whatFind;
PathAndWord(String path, String whatFind) {
this.path = path;
this.whatFind = whatFind;
}
boolean isProperlyInitialized() {
return path != null && whatFind != null;
}
}
public void askUserPathAndWord() {
try {
tryToAskUserPathAndWord();
} catch (IOException | RuntimeException e) {
System.out.println("Wrong input!");
e.printStackTrace();
} catch (InterruptedException e) {
System.out.println("Interrupted.");
e.printStackTrace();
}
}
private void tryToAskUserPathAndWord() throws IOException, InterruptedException {
PathAndWord pathAndWord = readPathAndWord();
if (pathAndWord.isProperlyInitialized()) {
performScan(pathAndWord, "GameOver.tmp");
System.out.println("Thank you!");
} else {
System.out.println("You did not enter anything");
}
}
private PathAndWord readPathAndWord() throws IOException {
System.out.println("Please, enter a Path and Word (which you want to find):");
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
String path = readPath(bufferedReader);
String whatFind = readWord(bufferedReader);
return new PathAndWord(path, whatFind);
}
private String readPath(BufferedReader bufferedReader) throws IOException {
System.out.println("Please enter a Path:");
return bufferedReader.readLine();
}
private String readWord(BufferedReader bufferedReader) throws IOException {
System.out.println("Please enter a Word:");
return bufferedReader.readLine();
}
private void performScan(PathAndWord pathAndWord, String endOfWorkFileName) throws InterruptedException {
BlockingQueue<File> queue = new LinkedBlockingQueue<File>();
File endOfWorkFile = new File(endOfWorkFileName);
CountDownLatch latch = new CountDownLatch(2);
FolderScan folderScan = new FolderScan(pathAndWord.path, queue, latch,
endOfWorkFile);
FileScan fileScan = new FileScan(pathAndWord.whatFind, queue, latch,
endOfWorkFile);
Executor executor = Executors.newCachedThreadPool();
executor.execute(folderScan);
executor.execute(fileScan);
latch.await();
}
类路径和单词{
最终字符串路径;
最终字符串whatFind;
PathAndWord(字符串路径、字符串whatFind){
this.path=path;
this.whatFind=whatFind;
}
布尔值IsPropertyInitialized(){
返回路径!=null&&whatFind!=null;
}
}
公共无效askUserPathAndWord(){
试一试{
trytoaskuerpathandword();
}捕获(IOException | RuntimeException e){
System.out.println(“输入错误!”);
e、 printStackTrace();
}捕捉(中断异常e){
System.out.println(“中断”);
e、 printStackTrace();
}
}
私有void tryToAskUserPathAndWord()引发IOException、InterruptedException{
PathAndWord PathAndWord=readPathAndWord();
if(pathAndWord.isPropertyInitialized()){
performScan(pathAndWord,“GameOver.tmp”);
System.out.println(“谢谢!”);
}否则{
System.out.println(“您没有输入任何内容”);
}
}
private PathAndWord readPathAndWord()引发IOException{
System.out.println(“请输入路径和单词(您要查找):”;
BufferedReader BufferedReader=新的BufferedReader(新的InputStreamReader(System.in));
字符串路径=读取路径(bufferedReader);
字符串whatFind=readWord(bufferedReader);
返回新路径和单词(路径,whatFind);
}
私有字符串读取路径(BufferedReader BufferedReader)引发IOException{
System.out.println(“请输入路径:”);
返回bufferedReader.readLine();
}
私有字符串读取字(BufferedReader BufferedReader)引发IOException{
System.out.println(“请输入一个单词:”);
返回bufferedReader.readLine();
}
private void performScan(路径和文字路径和文字,字符串endOfWorkFileName)引发中断异常{
BlockingQueue=新建LinkedBlockingQueue();
文件endOfWorkFile=新文件(endOfWorkFileName);
倒计时闩锁=新倒计时闩锁(2);
FolderScan FolderScan=新FolderScan(路径和Word.path、队列、闩锁、,
endOfWorkFile);
FileScan FileScan=新的FileScan(pathAndWord.whatFind、queue、lack、,
endOfWorkFile);
Executor Executor=Executors.newCachedThreadPool();
执行器。执行(folderScan);
executor.execute(fileScan);
satch.wait();
}
问题:
- 如何检查用户输入的路径是否正确李>
- 如果路径不正确
显示
李>路径错误的消息!请重试
- 能够检查word-
是否正确李>whatFind
- 需要在点之前做什么
如果可以的话,在本地检查数据是一个很好的习惯。稍后调用该方法时,您可以确保它返回您期望的结果。您可以创建一个
新文件(“givenPath”)
。捕获异常,以便知道路径不正确。如果有效,请检查它是否为dir.is notnew File(path).exists()
和/或newFile(path).isDirectory()
足够了吗?@aranoid您能否更好地显示此变体?虽然此代码可能会解决问题,但最好在代码中添加一些级别的描述来解释它如何解决问题(或在本例中为问题)。@nazar_art我指的是作为答案发布的Petr代码。如果作者添加一行文字说明如何解决问题,或说明其作用等,则仅代码答案通常更有用。
private String readPath(BufferedReader bufferedReader) throws IOException {
boolean ok = false;
do {
System.out.println("Please enter a Path:");
File f = new File(bufferedReader.readLine());
if(f.exists() && f.isDirectory())
ok = true;
else
System.err.println("Doesn't exist or is not a folder.");
} while(!ok);
return f.getAbsolutePath();
}