private static void removeUnusedParameterViaChangeSignature(
        final PsiMethod psiMethod, final Collection<PsiElement> parametersToDelete) {
      ArrayList<ParameterInfoImpl> newParameters = new ArrayList<ParameterInfoImpl>();
      PsiParameter[] oldParameters = psiMethod.getParameterList().getParameters();
      for (int i = 0; i < oldParameters.length; i++) {
        PsiParameter oldParameter = oldParameters[i];
        if (!parametersToDelete.contains(oldParameter)) {
          newParameters.add(
              new ParameterInfoImpl(i, oldParameter.getName(), oldParameter.getType()));
        }
      }

      ParameterInfoImpl[] parameterInfos =
          newParameters.toArray(new ParameterInfoImpl[newParameters.size()]);

      ChangeSignatureProcessor csp =
          new ChangeSignatureProcessor(
              psiMethod.getProject(),
              psiMethod,
              false,
              null,
              psiMethod.getName(),
              psiMethod.getReturnType(),
              parameterInfos);

      csp.run();
    }
    public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {
      if (!CodeInsightUtilBase.preparePsiElementForWrite(descriptor.getPsiElement())) return;
      final PsiMethod psiMethod =
          PsiTreeUtil.getParentOfType(descriptor.getPsiElement(), PsiMethod.class);
      if (psiMethod != null) {
        final ArrayList<PsiElement> psiParameters = new ArrayList<PsiElement>();
        final RefElement refMethod = myManager != null ? myManager.getReference(psiMethod) : null;
        if (refMethod != null) {
          for (final RefParameter refParameter : getUnusedParameters((RefMethod) refMethod)) {
            psiParameters.add(refParameter.getElement());
          }
        } else {
          final PsiParameter[] parameters = psiMethod.getParameterList().getParameters();
          for (PsiParameter parameter : parameters) {
            if (Comparing.strEqual(parameter.getName(), myHint)) {
              psiParameters.add(parameter);
              break;
            }
          }
        }
        final PsiModificationTracker tracker = psiMethod.getManager().getModificationTracker();
        final long startModificationCount = tracker.getModificationCount();

        removeUnusedParameterViaChangeSignature(psiMethod, psiParameters);
        if (refMethod != null && startModificationCount != tracker.getModificationCount()) {
          myProcessor.ignoreElement(refMethod);
        }
      }
    }
    public void applyFix(@NotNull final Project project, @NotNull ProblemDescriptor descriptor) {
      final PsiElement element = descriptor.getPsiElement();
      final PsiMethod method = PsiTreeUtil.getParentOfType(element, PsiMethod.class);
      LOG.assertTrue(method != null);
      PsiParameter parameter = PsiTreeUtil.getParentOfType(element, PsiParameter.class, false);
      if (parameter == null) {
        final PsiParameter[] parameters = method.getParameterList().getParameters();
        for (PsiParameter psiParameter : parameters) {
          if (Comparing.strEqual(psiParameter.getName(), myParameterName)) {
            parameter = psiParameter;
            break;
          }
        }
      }
      if (parameter == null) return;
      if (!CommonRefactoringUtil.checkReadOnlyStatus(project, parameter)) return;

      final PsiExpression defToInline;
      try {
        defToInline =
            JavaPsiFacade.getInstance(project)
                .getElementFactory()
                .createExpressionFromText(myValue, parameter);
      } catch (IncorrectOperationException e) {
        return;
      }
      final PsiParameter parameterToInline = parameter;
      inlineSameParameterValue(method, parameterToInline, defToInline);
    }
 private static void appendMethodParameters(
     StringBuffer buf, PsiMethod method, boolean showNames) {
   PsiParameter[] params = method.getParameterList().getParameters();
   buf.append('(');
   for (int i = 0; i < params.length; i++) {
     if (i != 0) buf.append(", ");
     PsiParameter param = params[i];
     buf.append(param.getType().getPresentableText());
     if (showNames) {
       buf.append(' ');
       buf.append(param.getName());
     }
   }
   buf.append(')');
 }
    public static void removeParameter(final PsiMethod method, final PsiParameter parameter) {
      final PsiParameter[] parameters = method.getParameterList().getParameters();
      final List<ParameterInfoImpl> psiParameters = new ArrayList<ParameterInfoImpl>();
      int paramIdx = 0;
      final String paramName = parameter.getName();
      for (PsiParameter param : parameters) {
        if (!Comparing.strEqual(paramName, param.getName())) {
          psiParameters.add(new ParameterInfoImpl(paramIdx, param.getName(), param.getType()));
        }
        paramIdx++;
      }

      new ChangeSignatureProcessor(
              method.getProject(),
              method,
              false,
              null,
              method.getName(),
              method.getReturnType(),
              psiParameters.toArray(new ParameterInfoImpl[psiParameters.size()]))
          .run();
    }