I will explain about Spring Security using oauth 2.0 in details with runnable code. I will explain how to create a authorization server and generate authorization token and use the same to access the protected resources.
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In this post I will discuss how to approach any design problem and we will design a parking lot for an example.
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I struggled a lot while trying to send an image in form data in angular js to REST end point. I hope this article will help you to successfully send an image in form data.
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In this article I will explain how to properly use synchronization in Java. Many developers think that synchronization is for mutual exclusion. But there is more to it. You can end up with hard to detect bug if synchronization is not properly used.
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When I ask a candidate to code a Breadth First Search in Java, he does it using array of nodes and assuming that nodes are always integer. But when I go deeper and ask them to generalize the Graph where the nodes can be any object like Integer, String or any Custom object which is basically a Generic Graph and ask them to code the BFS for the same, they struggle a lot.
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Annotations are really great. They explain a lot about your method, field or class. For example if you annotate a method as @Test, it will convey the information to Junit to run it as a test method. @Override annotation makes the compiler to check that if the method presents in the super class or not. In fact it may help you to resolve some silly mistakes. In this post I will explain how to write your own custom annotation.
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In this post I will discuss the power of Java enums. Java enums are very powerful. Generally most java developers are not aware of the full potential of the Java enums. I will show you how Java enums weigh much higher over int constants.
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In this article I will explain how to write an Email Service using Spring Boot. I will also show you how to use Rabbit MQ to receive the message to be sent using the email service.
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Feign acts as a proxy to hide the actual services. The user has the impression that it's getting the response from only one service. But behind the scene Feign acts on behalf of the user and requests the corresponding services to get or set data. In this article I will explain how we can send form data using Feign to an actual service.
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Programmers evolve. There are many evolving phases in the career of a programmer. Many learn in the hard way and many in the smart way. In this article I will share 7 killer tips that differentiates a good Programmer from the average or so called good programmers and help you learn the smart way.
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