Java – Getting ‘Access Denied’ when trying to access file from C:\ProgramData

javauacwindowswindows 7

Our clients are frequently reporting issue that they are getting "Access Denied" exception when they used to run application that has been installed with downloaded setup file. Our installer, installs executable on 'Program Files' and creates configuration files at C:\ProgramData. Once installation is done, our application automatically run first time. Whenever user going to run it next time, it throws Access is denied as program can not able to access configuration files at C:\ProgramData.

Yes.. "Run as Administrator" is the solution but we can not ask our all paid users to do such. I have searched option at can set privileges by some alternative way then manually run executable as "Run as Administrator".

I have found that help page but that's not working for me. My application is java desktop application so I have created .exe.manifest file and put that manifest file into executable where images and other product's properties files resides.

Manifest does not work for me and I am still getting "Access Denied" issue.

This is content of manifest file –

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0"> 
  <assemblyIdentity version="1.0.0.0"
     processorArchitecture="X86"
     name="<product_name>"
     type="win32"/> 
  <description>Description of your application</description> 
  <!-- Identify the application security requirements. -->
  <trustInfo xmlns="urn:schemas-microsoft-com:asm.v2">
    <security>
      <requestedPrivileges>
        <requestedExecutionLevel
          level="requireAdministrator"
          uiAccess="true"/>
        </requestedPrivileges>
       </security>
  </trustInfo>
</assembly>

How I can attach the application manifest to the executable as I have only copied that manifest where images and other product's properties files resides ?

Is there any thing need to update in manifest file as I have copied as-is content except ?

Exception —

java.io.FileNotFoundException: C:\ProgramData\.<poduct_name>\config\<Product_Name>.xml (Access is denied) stacktrace javax.xml.transform.TransformerException: java.io.FileNotFoundException: C:\ProgramData\.<Product_Name>\config\<Product_Name>.xml (Access is denied) at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.getOutputHandler(Unknown Source) at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Unknown Source) at com.<Product_Name>.main.dr.a(Unknown Source) at com.<Product_Name>.main.dr.a(Unknown Source) at com.<Product_Name>.main.dr.a(Unknown Source) at com.<Product_Name>.main.h.k(Unknown Source) at com.<Product_Name>.main.ay.run(Unknown Source) Caused by: java.io.FileNotFoundException: C:\ProgramData\.<Product_Name>\config\<Product_Name>.xml (Access is denied) at java.io.FileOutputStream.open(Native Method) at java.io.FileOutputStream. (Unknown Source) at java.io.FileOutputStream. (Unknown Source) ... 7 more --------- java.io.FileNotFoundException: C:\ProgramData\.<Product_Name>\config\<Product_Name>.xml (Access is denied) at java.io.FileOutputStream.open(Native Method) at java.io.FileOutputStream. (Unknown Source) at java.io.FileOutputStream. (Unknown Source) at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.getOutputHandler(Unknown Source) at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Unknown Source) at com.<Product_Name>.main.dr.a(Unknown Source) at com.<Product_Name>.main.dr.a(Unknown Source) at com.<Product_Name>.main.dr.a(Unknown Source) at com.<Product_Name>.main.h.k(Unknown Source) at com.<Product_Name>.main.ay.run(Unknown Source) and the cause isjava.io.FileNotFoundException: C:\ProgramData\.<Product_Name>\config\<Product_Name>.xml (Access is denied)

Best Answer

~~The problem is because the user settings file is stored in the wrong place.~~

Only executable binaries and related resources belong in the ProgramData directory ("C:\Program Files..."), and this data should only change when a user with administrator rights installs or updates a program installation. Any configuration or data that the user needs to change must be kept in places where the user has rights to edit, such as their home folder, "My Documents", their HKEY_CURRENT_USER Registry key, or better yet, their AppData directory.

~~You can read more about these Windows programming requirements for user data storage here, and here is how some people have done this in Java. Hope that helps get you fixed up!~~

On second thought, perhaps using a tool like PROCMON.EXE would help narrow down the specifics of the denial--because it will show you whether the programming is opening the file/directory for reading, writing-with-all-permissions, trying to create a file that already exists, etc.

Read all text from a file

Java 11 added the readString() method to read small files as a String, preserving line terminators:

String content = Files.readString(path, StandardCharsets.US_ASCII);

For versions between Java 7 and 11, here's a compact, robust idiom, wrapped up in a utility method:

static String readFile(String path, Charset encoding)
  throws IOException
{
  byte[] encoded = Files.readAllBytes(Paths.get(path));
  return new String(encoded, encoding);
}

Read lines of text from a file

Java 7 added a convenience method to read a file as lines of text, represented as a List<String>. This approach is "lossy" because the line separators are stripped from the end of each line.

List<String> lines = Files.readAllLines(Paths.get(path), encoding);

Java 8 added the Files.lines() method to produce a Stream<String>. Again, this method is lossy because line separators are stripped. If an IOException is encountered while reading the file, it is wrapped in an UncheckedIOException, since Stream doesn't accept lambdas that throw checked exceptions.

try (Stream<String> lines = Files.lines(path, encoding)) {
  lines.forEach(System.out::println);
}

This Stream does need a close() call; this is poorly documented on the API, and I suspect many people don't even notice Stream has a close() method. Be sure to use an ARM-block as shown.

If you are working with a source other than a file, you can use the lines() method in BufferedReader instead.

Memory utilization

The first method, that preserves line breaks, can temporarily require memory several times the size of the file, because for a short time the raw file contents (a byte array), and the decoded characters (each of which is 16 bits even if encoded as 8 bits in the file) reside in memory at once. It is safest to apply to files that you know to be small relative to the available memory.

The second method, reading lines, is usually more memory efficient, because the input byte buffer for decoding doesn't need to contain the entire file. However, it's still not suitable for files that are very large relative to available memory.

For reading large files, you need a different design for your program, one that reads a chunk of text from a stream, processes it, and then moves on to the next, reusing the same fixed-sized memory block. Here, "large" depends on the computer specs. Nowadays, this threshold might be many gigabytes of RAM. The third method, using a Stream<String> is one way to do this, if your input "records" happen to be individual lines. (Using the readLine() method of BufferedReader is the procedural equivalent to this approach.)

Character encoding

One thing that is missing from the sample in the original post is the character encoding. There are some special cases where the platform default is what you want, but they are rare, and you should be able justify your choice.

The StandardCharsets class defines some constants for the encodings required of all Java runtimes:

String content = readFile("test.txt", StandardCharsets.UTF_8);

The platform default is available from the Charset class itself:

String content = readFile("test.txt", Charset.defaultCharset());

Note: This answer largely replaces my Java 6 version. The utility of Java 7 safely simplifies the code, and the old answer, which used a mapped byte buffer, prevented the file that was read from being deleted until the mapped buffer was garbage collected. You can view the old version via the "edited" link on this answer.

HttpListener Access Denied

Yes you can run HttpListener in non-admin mode. All you need to do is grant permissions to the particular URL. e.g.

netsh http add urlacl url=http://+:80/MyUri user=DOMAIN\user

Documentation is here.

Best Answer

Related Solutions

Java – How to create a Java string from the contents of a file

Read all text from a file

Read lines of text from a file

Memory utilization

Character encoding

HttpListener Access Denied

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