0 
import java.io.*;
import java.util.StringTokenizer;

class FileCopy
{
        public static void main(String[] args) throws IOException
        {
                String infile = null;
                String outfile = null;
                BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));    

                if (args.length >= 2) //both files given via command line
                {
                        infile = args[0];
                        if (fileExists(infile) == false)
                        {
                                infile = getInputFile();
                        }
                        outfile = args[1];
                }
                else if (args.length == 1) //input file given via command line
                {
                        infile = args[0];
                        outfile = getOutputFile();
                }
                else //no files given on command line
                {
                        infile = getInputFile();
                        outfile = getOutputFile();
                }

                //create file objects to use
                File in = new File(infile);
                File out = new File(outfile);

                /*
                 *rest of code
                 */
        }

        //get the input file from the user if given file does not exist
        public static String getInputFile() throws IOException
        {
                BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
                String fileName = null;
                boolean haveFile = false;

                do
                {
                        System.out.println("Enter a valid filename:");
                        System.out.print(">> ");
                        fileName = stdin.readLine();
                        haveFile = fileExists(fileName);
                }while(haveFile == false);

                return fileName;        
        }

        //get the output file and test things
        public static String getOutputFile()
        {
                return null;
        }

        //check the given file to see if it exists in the current working directory
        public static boolean fileExists(String n)
        {
                boolean exist = false;
                if (n.length() != 0)
                {
                        File tmp = new File(n);
                        exist = tmp.exists();
                }
                return exist;
        }
}

我在第 53 行调用 fileExists 时遇到问题。据我所知，语法是正确的，但它只是无限期地停留在 do 循环中。在 Jcreator 中单步执行该程序并没有找到任何解决方案，尽管有趣的是，该程序直接跳过了第 53 行而没有跳转到 fileExists。有什么想法有什么问题吗？

4

1 回答 1

2

之后File tmp = new File(n);，添加System.out.println(tmp.getAbsolutePath());。它可能会立即指出路径文件名中出了什么问题。

于 2012-09-13T21:42:47.980 回答