void ( @NotNull PsiMethodCallExpression expression) { super.visitMethodCallExpression(expression); final Project project = expression.getProject(); final JavaPsiFacade psiFacade = JavaPsiFacade.getInstance(project); final PsiClass stringClass = psiFacade.findClass(CommonClassNames.JAVA_LANG_STRING, expression.getResolveScope()); if (stringClass == null) { return; } final PsiClassType stringType = psiFacade.getElementFactory().createType(stringClass); if (!MethodCallUtils.isCallToMethod(expression, CommonClassNames.JAVA_LANG_STRING, stringType, "concat", stringType)) { return; } final PsiExpressionList argumentList = expression.getArgumentList(); final PsiExpression[] arguments = argumentList.getExpressions(); if (arguments.length != 1) { return; } if (ExpressionUtils.isVoidContext(expression)) return; registerMethodCallError(expression); }