Hey I need to bypass the validation for substring whiteList in the string str but the rest of the string needs to be validated for the special characters ‘<‘, ‘>’, ‘$’, ‘#’, ‘@’. Assuming that substring is not repeated anywhere else in the main…
Tag: java
Spring boot won’t connect to Postgres database
I am trying to learn Spring Boot with a tutorial. I have the code and the database, but I keep getting a Hibernate ERROR whenever I try to connect the two… This is the Error I get: I have the dependency set up in my pom.xml: The StudentService And the StudentController class application.properties: Unfo…
Ldap AD Authentication in Spring Security
I have a login page in my application where I want to validate the entered username/password against Ldap AD. I am thinking of creating a bind and get a context. If bind is successful that means user is authenticated. In Java I have achieved it like this: Above code is perfectly working for me. I want to impl…
How to verify if a Kafka Topic is not empty meaning has at least 1 message?
I am writing a little Kafka metrics exporter (Yes there are loads available like prometheus etc but I want a light weight custom one. Kindly excuse me on this). As part of this I would like to know as soon as first message is received (or topic has messages) in a Kafka topic. I am using Spring Boot and Kafka.
When not to use volatile，it still can see the changes which issued by other thread
if it does not have the following codes, it will not show “end”. if it has these codes, it will probably show “end”. Sometimes it does not show. when is less than 598 or not have these codes, like use 550, it will not show “end”. when is 598, it will probably show “en…
Messing around with graphics in Java
I want to make an animation of an ellipse growing and shrinking in length. The animation should be continuous, so I want the length of the ellipse to grow to a certain point and then shrink back to its original for as long as the program is running. I already have the animation part of the program done, and I…
How to increase Parse Limit from 15000 in Graphql Using Quarkus
I am using an Angular application with Graphql to communicate with a Java/Quarkus backend. There is a situation where a large object is generated and I am attempting to manipulate it in the backend. An error occurs: Invalid Syntax : More than 15000 parse tokens have been presented. To prevent Denial Of Servic…
What is the difference between chars() and codePoints() method in CharSequence interface?
I read javadoc, but don’t understand the differences, both of them return same result. Also can anyone explain what is ‘zero-extending’ means? Javadoc of chars() method Returns a stream of int zero-extending the char values from this sequence. Any char which maps to a surrogate code point is…
method in class cannot be applied to give types when using generic methods
I have this code that is meant to count all duplicates in any given generic type list If I were to uncomment the header that takes int[] instead of T[], then it works perfectly fine. However, once I try to use a generic type I get the error: Why is this? Shouldn’t int[] be considered as T[]? I suspect t…
How to make auto refreshing on recyclerview Android while getting data from firebase firestore
I added a swipe SwipeRefreshLayout but the data only show when I swipe down to refresh. If I don’t refresh the data didn’t show. I want an auto refresh on the background when an activity is created. This is my XML After getting data from the firebase I added it to the list and add that list into t…