SmartGit/Hg is a graphical user interface for Git and Mercurial which can work with SVN repositories. It supports cloning from common repository providers (e.g., GitHub, Assembla), assists Git newbies, and also offers the advanced, powerful Git features. It provides several tools to help create clean commits, for example by allowing the user to commit just parts of changes files and reordering and squashing unpushed commits. If you are using GitHub or GitHub Enterprise, SmartGit/Hg can work easily with pull requests (creation, resolving) and commit comments. SmartGit/Hg ships with a built-in SSH client, file comparer, and merge tool which are capable of syntax coloring for many languages.
SVNKit is a pure Java Subversion (SVN) client library. This means that users of the library (i.e. Java applications) do not have to include svn native binaries or javahl bindings to work with subversion repositories. It is not only a 100% Java replacement for javahl bindings, but also a library that provides a high level of control over subversion repository operations.