diff --git a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/JiraRemoteApi.java b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/JiraRemoteApi.java
index d4bf05c8460f..22e93a9d26ee 100644
--- a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/JiraRemoteApi.java
+++ b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/JiraRemoteApi.java
@@ -24,14 +24,14 @@ public abstract class JiraRemoteApi {
   }
 
   @NotNull
-  public abstract List<Task> findTasks(String jql, int max) throws Exception;
+  public abstract List<Task> findTasks(@NotNull String jql, int max) throws Exception;
 
   @Nullable
-  public abstract Task findTask(String key) throws Exception;
+  public abstract Task findTask(@NotNull String key) throws Exception;
 
-  public abstract void setTaskState(Task task, TaskState state) throws Exception;
+  public abstract void setTaskState(@NotNull Task task, @NotNull TaskState state) throws Exception;
 
-  public abstract void updateTimeSpend(LocalTask task, String timeSpent, String comment) throws Exception;
+  public abstract void updateTimeSpend(@NotNull LocalTask task, @NotNull String timeSpent, String comment) throws Exception;
 
   @NotNull
   public final String getVersionName() {
diff --git a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/JiraRestApi.java b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/JiraRestApi.java
index 3a97d83ce44d..a56b1cf1091a 100644
--- a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/JiraRestApi.java
+++ b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/JiraRestApi.java
@@ -53,7 +53,7 @@ public abstract class JiraRestApi extends JiraRemoteApi {
 
   @Override
   @NotNull
-  public final List<Task> findTasks(String jql, int max) throws Exception {
+  public final List<Task> findTasks(@NotNull String jql, int max) throws Exception {
     GetMethod method = getMultipleIssuesSearchMethod(jql, max);
     String response = myRepository.executeMethod(method);
     List<JiraIssue> issues = parseIssues(response);
@@ -68,7 +68,7 @@ public abstract class JiraRestApi extends JiraRemoteApi {
 
   @Override
   @Nullable
-  public final JiraRestTask findTask(String key) throws Exception {
+  public final JiraRestTask findTask(@NotNull String key) throws Exception {
     GetMethod method = getSingleIssueSearchMethod(key);
     return new JiraRestTask(parseIssue(myRepository.executeMethod(method)), myRepository);
   }
@@ -95,7 +95,7 @@ public abstract class JiraRestApi extends JiraRemoteApi {
   protected abstract JiraIssue parseIssue(String response);
 
   @Override
-  public void setTaskState(Task task, TaskState state) throws Exception {
+  public void setTaskState(@NotNull Task task, @NotNull TaskState state) throws Exception {
     String requestBody = getRequestForStateTransition(state);
     LOG.debug(String.format("Transition: %s -> %s, request: %s", task.getState(), state, requestBody));
     if (requestBody == null) {
diff --git a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api2/JiraRestApi2.java b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api2/JiraRestApi2.java
index 8ace0cbdced0..0c9b647ee720 100644
--- a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api2/JiraRestApi2.java
+++ b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api2/JiraRestApi2.java
@@ -81,7 +81,7 @@ public class JiraRestApi2 extends JiraRestApi {
   }
 
   @Override
-  public void updateTimeSpend(LocalTask task, String timeSpent, String comment) throws Exception {
+  public void updateTimeSpend(@NotNull LocalTask task, @NotNull String timeSpent, String comment) throws Exception {
     LOG.debug(String.format("Time spend: %s, comment: %s", timeSpent, comment));
     PostMethod method = new PostMethod(myRepository.getRestUrl("issue", task.getId(), "worklog"));
     String request;
diff --git a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api20alpha1/JiraRestApi20Alpha1.java b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api20alpha1/JiraRestApi20Alpha1.java
index 14407f9ba91f..7de17945ac31 100644
--- a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api20alpha1/JiraRestApi20Alpha1.java
+++ b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/rest/api20alpha1/JiraRestApi20Alpha1.java
@@ -72,7 +72,7 @@ public class JiraRestApi20Alpha1 extends JiraRestApi {
   }
 
   @Override
-  public void updateTimeSpend(LocalTask task, String timeSpent, String comment) throws Exception {
+  public void updateTimeSpend(@NotNull LocalTask task, @NotNull String timeSpent, String comment) throws Exception {
     throw new Exception(TaskBundle.message("jira.failure.no.time.spent"));
   }
 
diff --git a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/soap/JiraSoapApi.java b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/soap/JiraSoapApi.java
index 9a6ddb19df1a..148432902a86 100644
--- a/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/soap/JiraSoapApi.java
+++ b/plugins/tasks/tasks-core/jira/src/com/intellij/tasks/jira/soap/JiraSoapApi.java
@@ -39,7 +39,7 @@ public class JiraSoapApi extends JiraRemoteApi {
 
   @NotNull
   @Override
-  public List<Task> findTasks(String query, int max) throws Exception {
+  public List<Task> findTasks(@NotNull String query, int max) throws Exception {
 
     // Unfortunately, both SOAP and XML-RPC interfaces of JIRA don't allow fetching *all* tasks from server, but
     // only filtered by some search term (see http://stackoverflow.com/questions/764282/how-can-jira-soap-api-not-have-this-method).
@@ -85,7 +85,7 @@ public class JiraSoapApi extends JiraRemoteApi {
 
   @Nullable
   @Override
-  public Task findTask(String key) throws Exception {
+  public Task findTask(@NotNull String key) throws Exception {
     try {
       List<Task> tasks = processRSS(new GetMethod(myRepository.getUrl() + RSS_ISSUE_PATH + key + '/' + key + ".xml"));
       return tasks.isEmpty() ? null : tasks.get(0);
@@ -103,12 +103,12 @@ public class JiraSoapApi extends JiraRemoteApi {
   }
 
   @Override
-  public void setTaskState(Task task, TaskState state) throws Exception {
+  public void setTaskState(@NotNull Task task, @NotNull TaskState state) throws Exception {
     throw new Exception(TaskBundle.message("jira.failure.no.state.update"));
   }
 
   @Override
-  public void updateTimeSpend(LocalTask task, String timeSpent, String comment) throws Exception {
+  public void updateTimeSpend(@NotNull LocalTask task, @NotNull String timeSpent, String comment) throws Exception {
     throw new Exception(TaskBundle.message("jira.failure.no.time.spent"));
   }
 }