Question

I tried the following code,

File folder = new File("/path/of/the/directory");
File[] listOfFiles = folder.listFiles();

for (int i = 0; i < listOfFiles.length; i++) {
    if (listOfFiles[i].isFile()) {
        if ((listOfFiles[i].getName()).contains(".xml")) {
            Window.alert("File " + listOfFiles[i].getName());
        }
    }
}

But, I got this error:

No source code is available for type java.io.File; did you forget to inherit a required module ?

Can anyone help me to do the same using GWT?

Thanks in advance,
Gnik

Answer 1

Short answer

You cannot use the Java.io.File class in GWT.

Except if you use gwt-filesystem

“Large” answer

From groups :

You won’t be able to use java.io.File on the client.
You can’t access the client’s file system without using an Applet,
Flash, ActiveX, or other component to which the user has granted
permission.

You should go to the Google Documentation about the JRE Emulation Reference.

According to the documentation :

Google Web Toolkit includes a library that emulates a subset of the Java runtime library. The list below shows the set of JRE packages, types and methods that GWT can translate automatically. Note that in some cases, only a subset of methods is supported for a given type.

---

However, you can use the gwt-filesystem project :

This library adds browser-based FileSystem support to applications developed using Google Web Toolkit (GWT), based on the HTML5 FileSystem specification.