1, get all task assigned to a user
// its working.
List<Task> tasks = taskService.createTaskQuery().taskAssignee(userId).list()
2, get all task assigned to groups
//tasks list empty, its not working
List<Task> tasks = taskService.createTaskQuery().taskCandidateGroupIn(roles).list()
3, clam a task
//its working
taskService.claim(taskId, userId)
4, revoke a task
// i don't know this is the right way
taskService.claim(taskId,null)
5, start process instance
//its working
ProcessInstance processInstance = runtimeService.startProcessInstanceByKey(pdId, variables);
6, complete a task
//its working
taskService.complete(taskId,variables)
7, get from properties for a task
// its working
List<FormProperty> formList = formService.getTaskFormData(taskId).getFormProperties();
I want to make sure that i am doing in right way.. please correct if i am wrong
Update for answer
7) get from properties for a task
I have to loop through formList and using getId() and getValue() i got what i want
2) get all task assigned to groups
taskCandidateGroupIn(roles) // here roles must be List
FormProperty is an object that holds the information about the specific form property. If you look at the documentation, you will see how it is implemented.