NullPointerException when getting resources

Question

Hi,
I am trying to build a simple program to get a file resource. The code is fairly simple, with the next method in mypackage.MyClass:
File someMethod(String filename) {
         String name =
              this.getClass().getResource(filename).getFile();
        File file = new File(name);
return file;
}The project is organised as follows:
/src - the sources directory
/bin - the binaries directory
/resources - the directory where my file exists, let's say testfile.html
I try to call someMethod("resources/testfile.html") or
someMethod("../resources/testfile.html").
Also tried to set the classpath in the .ant file:
  <path id="classpath.project">
     <pathelement path="${dir.build}"/>
     <pathelement location="resources"/>
  </path>and then call someMethod("testfile.html").
Every time I get NullPointerException, IDE or command line.
Thanks for help!
l.

Answer 1

Hi,
I am trying to build a simple program to get a file
resource. The code is fairly simple, with the next
method in mypackage.MyClass:
File someMethod(String filename) {
String name =
this.getClass().getResource(filename).getFile();
File file = new File(name);
return file;
}The project is organised as follows:
/src - the sources directory
/bin - the binaries directory
/resources - the directory where my file exists, let's
say testfile.html
I try to call someMethod("resources/testfile.html") or
someMethod("../resources/testfile.html").
Also tried to set the classpath in the .ant file:
<path id="classpath.project">
<pathelement path="${dir.build}"/>
<pathelement location="resources"/>
</path>and then call someMethod("testfile.html").
Every time I get NullPointerException, IDE or command
line.
Thanks for help!
l.try the following:
String name = ClassLoader.getSystemClassLoader().getResource("../resources/" + filename).getFile();In the API you can find:
public URL getResource(String name)
Finds a resource with a given name. This method returns null if no resource with this name is found. The rules for searching resources associated with a given class are implemented by the * defining class loader of the class.
This method delegates the call to its class loader, after making these changes to the resource name: if the resource name starts with "/", it is unchanged; otherwise, the package name is prepended to the resource name after converting "." to "/". If this object was loaded by the bootstrap loader, the call is delegated to ClassLoader.getSystemResource.
The fact that the package is prepended to the resource might cause many problems
(as it also did within my project).
Remark that the .. might also cause problems (since I'm not sure if this is 100% pure java
or if this is 100% windows). I guess you should parse the filename in order to find the parent-directory.
kind regards,