如何从远程服务器为位于apache-tomcat WEB-INF / lib文件夹下的jar文件制作下载URL？

Question

Can anyone please tell me how to create a download link for a jar file which is located under /WEB-INF/lib folder of apache-tomcat . I am able to get the following jar file location as:

jar:file:/var/lib/tomcat7/webapps/cs/WEB-INF/lib/commons-fileupload-1.3.1.jar!/org/apache/commons/fileupload/disk/DiskFileItem.class

I want to build a download URL for this jar file so that I can download it from remote server to my local hard disk.

I have following code for finding java-version:

public static Map<String, String> getJarVersions(ICS ics, ServletContext context)
  {

    ServletContextResource resource = new ServletContextResource(context, "/WEB-INF/lib/");

    File file = null;
    try
    {
      file = resource.getFile();
    }
    catch (IOException e)
    {
      log.error("Error reading /WEB-INF/lib/ directory. ", e);
      return new HashMap(0);
    }
    File[] jarFiles = file.listFiles();
    Map<String, String> jarNameVersion = new HashMap();
    File[] arr$ = jarFiles;int len$ = arr$.length;
    for (int i$ = 0; i$ < len$;)
    {
      File jarFile = arr$[i$];

      JarFile jarfile = null;
      Manifest manifest = null;
      try
      {
        jarfile = new JarFile(jarFile);
        manifest = jarfile.getManifest();
        if (manifest != null)
        {
          Attributes attrs = manifest.getMainAttributes();
          String version = attrs.getValue("Implementation-Version");
          String vendor = attrs.getValue("Implementation-Vendor");
          if (vendor == null) {
            vendor = "Not applicable";
          }
          if (version == null) {
            version = "Not applicable";
          }
          version = version + " : " + vendor;
          jarNameVersion.put(jarFile.getName(), version);
        }
        else
        {
          jarNameVersion.put(jarFile.getName());
        }
        if (jarfile != null) {
          try
          {
            jarfile.close();
          }
          catch (IOException e)
          {
            log.error("Error thrown while closing the jar file ");
          }
        }
        i$++;
      }
      catch (IOException e)
      {
        log.error("Error reading JAR/MANIFEST file . ", e);
      }
      finally
      {
        if (jarfile != null) {
          try
          {
            jarfile.close();
          }
          catch (IOException e)
          {
            log.error("Error thrown while closing the jar file ");
          }
        }
      }
    }
    return jarNameVersion;
  }
}

Answer 1

You can't access straight to any resource under WEB-INF folder, since it is protected by tomcat from url access requests.

If you need to access any resource from within WEB-INF, you should build a java component (servlet, filter, controller, etc) to access this WEB-INF elements and return them.