admin We will sort a linked list in optimal way here. We will use “LeetCode 148. Sort List” problem as an example & solve it using Java language. The problem statement is: Given the head of a linked list, return the list after sorting it in ascending order.Follow up: Can you sort the linked list in … Read more
Quick Sort is a notable sorting algorithm. I will try to explain Quick Sort in simple terms. Let’s take an example: Input: 12 25 14 30 15 Output: 12 14 15 25 30 Suppose we have an unsorted array [12, 25, 14, 30, 15] as mentioned above. We will sort the unsorted array using Quick … Read more
Should I write an article explaining Merge Sort? There are tons of articles or videos online which explain Merge Sort. What new am I going to add? This is what I thought initially. But after a bit of hesitation, I have decided to write a post on Merge Sort. I would try to explain it … Read more
Today we will talk about a feature in Eclipse that lets you check Git revision history of a particular line. It can be very useful especially if you are working on large file with hundreds or thousands of lines of code. If you are one of the developers who work with legacy codebase, you are … Read more
I wrote a post sometime back regarding using Notepad++ as offline JSON validator. There I touched upon briefly on a couple of websites which I regularly use to format or validate JSON documents online. Those are https://jsonlint.com/ & http://jsonviewer.stack.hu/. I also mentioned that I prefer http://jsonviewer.stack.hu/ because it parses larger JSON files efficiently & doesn’t … Read more
I already wrote a post regarding a free tool for drawing sequence diagram by typing just text. But it lacked few features. Basically few days back, I was looking for some frame or boundary element that I can use to logically group some participants. I won’t say this requirement is part of standard UML sequence … Read more
If you are using JPA or Hibernate directly and got that exception while starting your application, there is one obvious reason for that. You forgot to add that table in MySQL database or any other database that you are using. But if the table is present, then most likely it is a database user permission … Read more
I have seen people getting confused about how a binary heap can be built in O(n) time complexity. There are online articles & videos regarding this. I will try to explain it in my own way as simply as possible. First thing first, a binary heap is a complete binary tree. All levels of complete … Read more
Well, practically there is not much difference. If you check Java doc, you will notice that Closeable interface extends AutoCloseable interface. But there is one difference & that explains the reason why AutoCloseable interface was introduced in Java 7. Closeable close() method can throw IOException only. And that made sense as you will be using … Read more
If you have come to this post, then you are facing xml parsing issue in Java. Caused by: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog. at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:203) One common issue for this is BOM character. So what is a BOM (BYTE ORDER MARK) character? When you have … Read more