java.nio.file.InvalidPathException : Illegal char <:> at index 2:

Question

我必须将类路径资源从一个包复制到另一个包。

我的程序是:

    public static void main(String[] args) throws IOException, URISyntaxException {

            ClassLoader classLoader = CopyFileToDirectoryTest.class.getClassLoader();
InputStream in = classLoader.getResourceAsStream("com/stackoverflow/main/Movie.class");

            URI uri = ClassLoader.getSystemResource("com/stackoverflow/json").toURI();
            Path path = Paths.get(uri.getPath(),"Movie.class");
            System.out.println(path);

            long copy = Files.copy(in, path, StandardCopyOption.REPLACE_EXISTING);
            System.out.println(copy);

        }

在 Files.copy 方法中我得到异常:

Exception in thread "main" java.nio.file.InvalidPathException: Illegal char <:> at index 2: /D:/Programs/workspaceEE/HibernateDemo/target/classes/com/stackoverflow/json
    at sun.nio.fs.WindowsPathParser.normalize(WindowsPathParser.java:182)
    at sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:153)
    at sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:77)
    at sun.nio.fs.WindowsPath.parse(WindowsPath.java:94)
    at sun.nio.fs.WindowsFileSystem.getPath(WindowsFileSystem.java:255)
    at java.nio.file.Paths.get(Paths.java:84)
    at com.stackoverflow.main.CopyFileToDirectoryTest.main(CopyFileToDirectoryTest.java:34)

如何解决？

解决方案

public static void main(String[] args) throws IOException, URISyntaxException {
        ClassLoader classLoader = CopyFileToDirectoryTest.class.getClassLoader();
        InputStream in = classLoader.getResourceAsStream("com//stackoverflow//main//Movie.class");
        URI uri = ClassLoader.getSystemResource("com//stackoverflow//json").toURI();
        String mainPath = Paths.get(uri).toString();
        Path path = Paths.get(mainPath, "Movie.class");
        System.out.println(path);
        long copy = Files.copy(in, path, StandardCopyOption.REPLACE_EXISTING);
        System.out.println(copy);
    }

此代码正确地将 Movie.class 从包 com/stackoverflow/main 复制到 com/stackoverflow/json。

Answer 1

问题是 Paths.get() 不期望从 uri.getPath() 生成的那种值。

解决方法:

URI uri = ClassLoader.getSystemResource("com/stackoverflow/json").toURI();
String mainPath = Paths.get(uri).toString();
Path path = Paths.get(mainPath ,"Movie.class");