Yet Another Blog

It's possbile to map GET parameters to an object in Spring. It's really useful when we need to pass lots of parameters as query string e.g. submitting a search form with many parameters. The following controller demonstrates this.   @RestController @RequestMapping("hello") public class MyController {     @RequestMapping(value = "data", method = RequestMethod.GET)     public MyRequest getData(MyRequest request){             return request;     }     public static class  MyRequest {         private String name;          private int age;         public String getName(){return this.name;}         public int getAge(){return this.name;}         public void setName(String name){this.name=name;}          public void setAge(int age){this.age=age;}     } } Following GET request will create a MyRequest object with age=10 and name=Nayan GET hello/data?age=10&name=Nayan As we're sending the request object as response we'll get the follo

URL parameters are automatically sent as state parameters in angular-ui-router . All we need to do is declare the parameter names in state configuration. Here is an example of state configuration: .state('home.profile', {     url: '/profile?id',     templateUrl: 'templates/profile.html',     controller: 'ProfileCtrl' }) Here we've declared a parameter id in url attribute.  Now if we hit the url with parameter id e.g /profile?id=1234343 , w e'll be able to receive id=1234343 in state params.  We'll also be able to pass state parameter through ui-sre f lik e the following: <a ui-sref="home.profile({id: '1234343' })">Go to profile</a> Here is an example controller that demonstrates how to receive the parameter : .controller('ProfileCtrl', ['$scope', '$stateParams',     function ($scope, $stateParams) {         $scope.id = $stateParams.id; // id will be 1234343          } ])

Why background task? There are tons of examples where we often need to run a task in background e.g. sending an email, sms or notification, writing some log in file etc. If a task is not required to maintain atomicity and can be executed after some delay, it's a good candidate to run in background.   How to run tasks in background in Java? In Java, the easiest way to run a task in background is to create a new thread and execute it. It's quite simple. Here is how to do this: new Thread(new Runnable(){ @Override public void run(){ // your background task } }).start(); It's easy! But there are some maintenance problem with the above code. The major problem is - there is no way to control how many background tasks we want to run simultaneously. For example, if 1000 users registers in your application at a time and you create 1000 background threads to send them a confirmation email, maybe you'll be in trouble. So you ne