TreeToString
Tree#toString shouldn't be used for Trees deriving from the code being compiled, as it discards whitespace and comments.

The problem

Tree#toString shouldn’t be used for Trees deriving from the code being compiled, as it discards whitespace and comments.

This check only runs inside Error Prone code. Suggested replacements include:

Prefer VisitorState#getConstantExpression for escaping constants in generated code.
VisitorState#getSourceForNode : it will give you the original source text. Note that for synthetic trees (e.g.: implicit constructors), that source may be null.
If the string representation was being used for comparison with keywords like this and super, try tree.getName().contentEquals("this")
One can also get the symbol name and use it for comparison : ASTHelpers.getSymbol(tree).getSimpleName().toString()

Suppress false positives by adding the suppression annotation @SuppressWarnings("TreeToString") to the enclosing element.