### Question:
Index implements Comparable<Index>, Serializable { public boolean isSharedOrHasSharedChildren() { if (isShared()) { return true; } if (this instanceof FileIndex) { return false; } else { List<Index> children = getIndexList(this); for (Index child : children) { if (child.isFolder()) { FolderIndex subfolder = (FolderIndex) child; if (subfolder.getSharedFlag()) { return true; } } } } return false; } Index(KeyPair fileKeys);  Index(KeyPair fileKeys, String name, FolderIndex parent); KeyPair getFileKeys(); PublicKey getFilePublicKey(); String getName(); void setName(String name); void setParent(FolderIndex parent); void decoupleFromParent(); FolderIndex getParent(); FolderIndex getSharedTopFolder(); boolean isSharedOrHasSharedChildren(); String getFullPath(); File asFile(File root); abstract boolean isShared(); abstract Set<String> getCalculatedUserList(); abstract KeyPair getProtectionKeys(); abstract boolean isFolder(); abstract boolean canWrite(); boolean isFile(); @Override int compareTo(Index other); @Override boolean equals(Object obj); @Override int hashCode(); @Override abstract String toString(); static List<Index> getIndexList(Index node);  }### Answer:
@Test public void testHasShared() { dir2.share(generateRSAKeyPair(EncryptionUtil.RSA_KEYLENGTH.BIT_512)); Assert.assertTrue(root.isSharedOrHasSharedChildren()); Assert.assertTrue(dir1.isSharedOrHasSharedChildren()); Assert.assertTrue(dir2.isSharedOrHasSharedChildren()); Assert.assertFalse(child1.isSharedOrHasSharedChildren()); Assert.assertFalse(child2.isSharedOrHasSharedChildren()); Assert.assertFalse(child3.isSharedOrHasSharedChildren()); dir2.unshare(); Assert.assertFalse(root.isSharedOrHasSharedChildren()); Assert.assertFalse(dir1.isSharedOrHasSharedChildren()); Assert.assertFalse(dir2.isSharedOrHasSharedChildren()); Assert.assertFalse(child1.isSharedOrHasSharedChildren()); Assert.assertFalse(child2.isSharedOrHasSharedChildren()); Assert.assertFalse(child3.isSharedOrHasSharedChildren()); }