What is the significance of the helper class java?

A Helper class java is a lesser known code smell where a coder has identified some miscellaneous, commonly used operations and attempted to make them reusable by lumping them together in an unnatural grouping. Successive developers have then come onto the project and not realised that the helper class exists, and have consequently rewritten the same common operations, or even created more Helper classes. But seriously, the main problem with Helper classes is that they are usually operations that act on a specific class, which obviously means in OO terms that they are suffering from an acute case of Feature Envy. This failure to package the behaviour with the data it acts on is why developers so often (in my experience) fail to find it. In addition to this, as you have already identified, SomethingSomethingHelper is actually a terrible name. It is undescriptive, and gives you no real inkling of what sort of operations the class does (it helps?), which also means that it's not obvious when adding new behaviours whether they belong in the Helper class or not. I would break up such classes along the lines of related behaviour that logically group together, and then rename the new classes to reflect what it does.