private JavaStructureNode createStructureTree(String source) {
JavaCompilation compilation = CompilationUtils.compileSource(source);
CompilationUnitDeclaration cu = compilation.getCompilationUnit();
JavaStructureNode root = new JavaStructureNode(Type.CU, null, null, cu);
cu.traverse(new JavaStructureTreeBuilder(root), (CompilationUnitScope) null);
return root;
}