Get package childs from a package - eclipse

Question

In Eclipse, how can I get the package's children?
Consider this example:
+ org.stack
org.stack.test
- StackTest.java
- Stack.java
When we do IPackageFragment.getChildren() in org.stack, the Eclipse JDT only returns the compilation unit (Java Files)! But I want all children of a package: all ICompilationUnits and all Packages.
In this example when I apply IPackageFragment.getChildren() in org.stack, I want the org.stack.test and the ICompilationUnit Stack.java...
How can I do this?

Answer 1

IPackageFragment is not the correct starting point. You have to ask a higher level for the packages:
IPackageFragment: A single package. It contains ICompilationUnits or IClassFiles, depending on whether the IPackageFragmentRoot is of type source or of type binary. Note that IPackageFragment are not organized as parent-children. E.g. net.sf.a is not the parent of net.sf.a.b. They are two independent children of the same IPackageFragmentRoot.
Have a look at this article about the AST

Answer 2

Here's some code that should be close to what you needed. (Since we're a bit past 2011, I doubt it will help you much, but maybe it will help somebody else.) Doubtless it can stand some improvement.
Since it doesn't seem possible to directly recurse downward from the IPackageFragment (as mentioned by Kai), the basic idea is to get the higher level IPackageFragmentRoot and filter it's children based on the original fragment's path.
PackageFragment originFragment; // = org.stack's fragment
try {
String fragmentPath = originFragment.getPath().toString();
IJavaElement parent = originFragment.getParent();
ArrayList<IJavaElement> allChildren =
new ArrayList<IJavaElement>();
if (parent instanceof IPackageFragmentRoot) {
IPackageFragmentRoot root = (IPackageFragmentRoot)parent;
IJavaElement[] rootChildren = root.getChildren();
// originsFragments includes the origin and all package
// fragments beneath it
List<IJavaElement> originsFragments =
Arrays.asList(rootChildren).stream()
.filter(c -> c.getPath().toString().startsWith(fragmentPath))
.collect(Collectors.toList());
allChildren.addAll(originsFragments);
// Gather the children of the package fragments
for (IJavaElement o : originsFragments) {
if (o instanceof IPackageFragment ) {
IPackageFragment oFragment = (IPackageFragment)o;
IJavaElement[] fChildren = oFragment.getChildren();
allChildren.addAll(Arrays.asList(fChildren));
}
}
}
} catch (JavaModelException e) {
e.printStackTrace();
}
An alternative inelegant solution would be to start with the original fragment's path and then use Java's file and directory facilities to descend through the directory hierarchy. Then, you can use IJavaProject's findPackageFragment(IPath path) to connect to the proper IPackageFragments.

Answer 3

you need to do it in a recursive way.
here's some pseudo code
findAllClasses(package, classesCollection) {
for(Class c: package.getClasses)
classesCollection.add(c.getResourcePath)
if(package.hasChildPackages)
for(Package p: packages)
findAllClasses(p, classesCollection)
}