java - UNC路径 "does not denote a properly accessible directory"异常如何解决？

Question

实现 Spring Integration 的 Spring boot 应用程序正在尝试为其入站 channel 适配器访问 UNC 路径。

问题是我收到以下异常:

 13:29:52.925 [task-scheduler-10] ERROR o.s.i.handler.LoggingHandler -
 org.springframework.messaging.MessagingException: The path
 [\\server\sharepath] does not denote a properly accessible directory.

我该如何解决这个问题？

集成配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:int="http://www.springframework.org/schema/integration"
       xmlns:int-file="http://www.springframework.org/schema/integration/file"
       xsi:schemaLocation="http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/integration/file http://www.springframework.org/schema/integration/file/spring-integration-file.xsd">

    <int-file:inbound-channel-adapter id="filesIn" directory="${input.path}" filename-regex="${file.pattern}">
        <int:poller id="poller" fixed-rate="500"/>
    </int-file:inbound-channel-adapter>

    <int-file:file-to-string-transformer input-channel="filesIn" output-channel="strings" delete-files="true" />

    <int:channel id="strings"/>

    <int:service-activator input-channel="strings"
                                   output-channel="output"
                                   ref="handler"/>

    <int-file:outbound-channel-adapter id="output"
                                       directory="${archive.path}"
                                       delete-source-files="true"/>

    <bean id="handler" class="com.giotta.service.DataHandler"/>

</beans>

此配置中使用的属性通过 -D 注入(inject)。

例如，java jar -Dinput.path="\\\\remote_host_ip\\path\\"

Answer 1

关于此事的配置最好分享一下。 inbound-channel-adapter 会导致您出现问题。

让我们看一下代码!

DefaultDirectoryScanner:

public final List<File> listFiles(File directory) throws IllegalArgumentException {
    File[] files = listEligibleFiles(directory);
    if (files == null) {
        throw new MessagingException("The path [" + directory
                + "] does not denote a properly accessible directory.");
    }
    return (this.filter != null) ? this.filter.filterFiles(files) : Arrays.asList(files);
}

protected File[] listEligibleFiles(File directory) {
    return directory.listFiles();
}

这是您看到该错误的地方。原因就在 java.io.File 中:

 * @return  An array of abstract pathnames denoting the files and
 *          directories in the directory denoted by this abstract pathname.
 *          The array will be empty if the directory is empty.  Returns
 *          {@code null} if this abstract pathname does not denote a
 *          directory, or if an I/O error occurs.
 *
public File[] listFiles() {

因此，您真的应该确保为您的目录使用正确的路径。

如果您在嵌入式 Servlet 容器模式下运行您的 Boot 应用程序，您应该考虑 webapp 工作目录。在这种情况下，您的 \server\sharepath 实际上应该是绝对路径，而不是相对路径。

更新

参见 java.io.File JavaDocs:

* <li> For Microsoft Windows platforms, the prefix of a pathname that contains a drive
 * specifier consists of the drive letter followed by <code>":"</code> and
 * possibly followed by <code>"\\"</code> if the pathname is absolute.  The
 * prefix of a UNC pathname is <code>"\\\\"</code>; the hostname and the share
 * name are the first two names in the name sequence.  A relative pathname that
 * does not specify a drive has no prefix.