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When you need to determine the number of digits in a number, the first approach that probably comes to my mind was always to convert it to a string first and then get the length of that...

I have an use case where we need to write a messages to durable/non durable queues instead of an address in AMQ broker. We don't want to write the messages to be sent address and route to respective queues of an address. can this be done using java.

I dont get why this question's answer is BABA according to kira learning and BBBB when i throw into w3schools. According to my own calculations, i got ABBA. According to java visualizer, w3schools and chatgpt, they changed both ab and ba to {"B", "B"} which does not make sense to me. My working: ba[0] = "A", which changes to ab[1] (B). ba = {"B",...

In this article, we explore OpenRewrite by Moderne, an automated refactoring ecosystem that helps developers eliminate technical debt within their repositories. Specifically, we focus on upgrading Spring Boot 2.x.x to Spring Boot 3 using OpenRewrite recipes with Maven, Gradle, or Moderne CLI. Learn how to save coding effort from hours or days to minutes with OpenRewrite's pre-packaged, open-source refactoring recipes for common framework migrations,...

I have definced following dependecies for otel in my java apache flink project: flinkShadowJar (platform("io.opentelemetry:opentelemetry-bom:1.35.0")); flinkShadowJar ("io.opentelemetry:opentelemetry-api"); flinkShadowJar ("io.opentelemetry:opentelemetry-sdk"); flinkShadowJar ("io.opentelemetry:opentelemetry-exporter-logging"); flinkShadowJar ("io.opentelemetry:opentelemetry-exporter-otlp"); flinkShadowJar ("io.opentelemetry.semconv:opentelemetry-semconv:1.24.0-alpha"); flinkShadowJar ("io.opentelemetry:opentelemetry-sdk-extension-autoconfigure"); But am getting following error when deploying flink pipeline: Caused by: io.opentelemetry.sdk.autoconfigure.spi.ConfigurationException: otel.metrics.exporter set to "otlp" but opentelemetry-exporter-otlp not found on classpath. Make sure to add it as a dependency. I want my app to deploy, and...

I would like to undarstand how tomcat and spring boot manage simuntenously requests on the same endpoint. @RestController public class SimpleRest { private static long counter; Random random = new Random(); @GetMapping("/counter") long restCounter() { try { Thread.sleep(random.nextInt(1000)); } catch (InterruptedException e) { throw new RuntimeException(e); } incrementCounter(); System.out.println("Thread name : " + Thread.currentThread().getName()); return getCounter(); } public void incrementCounter() { for(long i =...

I have 20000 records coming from server (Salesforce) I am limiting only 5000 records per a server call. I will be displaying only 5 records per page that leaves me with "4000" pagination, Therefore I cannot use the number approach it doesn't look good. I want to make the page number searchable, like below The problem I am facing here is I want to...

I have a class containing an array of objects, and get the following exception when attempting to deserialize: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `com.moneyfabric.core.acquiring.dao.data.MoneyMovementOriginatingAccount[]`: no String-argument constructor/factory method to deserialize from String value ('[{"paymentInstrumentId":"33f24ea6-6e6c-4b8f-b429-1fd76dce5c59","amount":{"currencyCode":"USD","decimalPlaces":2,"amount":5975}}]') at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 1, column: 187] (through reference chain: com.moneyfabric.server.core.acquiring.resource.data.MoneyMovementRq$Builder["debitAccounts"]) My class which causes this error when deserializing is as follows: @Data public class MoneyMovementRq { // Ensures we...

I want to enforce the student groups from the same series of students to be in the same Timeslot and in the same Room for a Course Type. This is my attempt: Constraint seminarsGroupedInTheSameTimeslot(ConstraintFactory constraintFactory){ return constraintFactory //select each 2 pair of different lessons .forEachUniquePair(Lesson.class, //with the same group Joiners.equal((lesson) -> lesson.getStudentGroup().getGroup()), //with the same series Joiners.equal((lesson) -> lesson.getStudentGroup().getName()), //with the same subject Joiners.equal(Lesson::getSubject),...

Yeti is ML style functional programming language, that runs on the JVM. message = "Hello world"; println message; Yeti was created to have a clean and minimal expressive language on the JVM that allows functional style programming, has static type inference and interfaces well with Java code. Some features Type infe...

I want to write automated API tests (in Java) for our micro-service. There are a lot of tools for this purpose. However, we want to automate another part of the tests too. Our APIs are secured, meaning that they require tokens in the header of request, and tokens have time-to-live time, so they will expire. Therefore, we need to automate the process of getting...

I'm new to Java and doing an exercise sheet, but there's something I could not understand. c1 is an object belonging to Top class. c2 is an object belonging to Medium class. Top is the main class, and Medium extends Top. m1 is a method in both classes. short s = 2; c1 = c2; c1.m1(new Medium(), s); c1.m1(c1, s); first output gives a...

I have a question. when i use konanc to link a jar, like that konanc -l xx.jar. The console shows that the jar package cannot be found I'm not sure whether i can use kotlin-native to link a jar because the online information shows that kotlin-native cannot add java library ,but the error message displayed in the console only indicates that it just cannot...

I have a work scenario that follows as such Producer loads data from a data lake source and publishes it to a Kafka topic this works fine. Consumer consumes from that topic, transforms the data shape and sends the data to an external api, that takes that data and saves it to a table in the db. At times, this external api throws exceptions...

The loading of keystore in Windows is very slow. It takes around 10 seconds to load all keystore in Window-My. I came across a few similar topics I encountered in stackoverflow, like this. I also tried to edit SecureRandom property like this post. All solutions are ineffective. Here is my code to load keystore in Windows: SunMSCAPI providerMSCAPI = new SunMSCAPI(); KeyStore ks =...

Learn how to mock static methods with Mockito. Master the art of unit testing for robust Java code. #Mockito #UnitTesting #JavaProgramming

I am writing a Spigot plugin that, upon death, should revive the player in a random place. I have a function that is looking for a "safe" place to revive, but because of it, the server is heavily loaded and it is running slowly. Is there any way to optimize the function, or do something so that the server does not reduce TPS at...

I'm working on integrating a printer (TG2480-H) functionality into my Java 17 application using the ESC/POS protocol. I've been using the PrinterOutputStream from a certain SDK to send commands to the printer, which works well for writing operations. However, I'm facing challenges with reading the status updates from the printer. The SDK offers read options for USB and SerialCOM connections, but my application is...

Don't go over the board with optimizations, let the language work for you. Story tell. Java upgrades give a performance boost for free. Benchmark, always.

I'm trying to implement this decryption method from java to c#: https://github.com/ecsec/open-ecard/blob/f66ae48e7bbb2bb27a524e12d3febabf162c17c7/ifd/ifd-protocols/pace/src/main/java/org/openecard/ifd/protocol/pace/SecureMessaging.java#L198C3-L198C90 /** * Decrypt the APDU. * * @param response the response * @param secureMessagingSSC the secure messaging ssc * @return the byte[] * @throws Exception the exception */ private byte[] decrypt(byte[] response, byte[] secureMessagingSSC) throws Exception { ByteArrayInputStream bais = new ByteArrayInputStream(response); ByteArrayOutputStream baos = new ByteArrayOutputStream(response.length - 10); // Status bytes...

I am trying to secure my spring boot application with spring securitys own csrf library. When I am sending requests to my backend authentication endpoint, the first request i send (without any cookies), gets 403 and my backend saying "Invalid CSRF token found for "http://localhost:8080/api/v1/auth/authenticate" That is sort of expected, since i didnt add the csrf token as a cookie. In the response, i...

Our application connects to IBM MQ CICS using JMS. It sends the CIH header, program name, and commarea as input to IBM MQ. It triggers the CICS and receives the data fine. However, if the COMMAREA has the value 'broken bar,' it does not. Why? comm area :: ABCD¦HIJ¦7002¦0010¦4¦34¦ ----> not working commarea: HG13;;EA;N; ----> working I have set the Encoding like following :...

so I have the following setup of a spring-boot application: org.springframework.boot:spring-boot-starter:3.2.4 com.ibm.db2:jcc:11.5.8.0 java.version=21 org.hibernate.orm:hibernate-core:6.4.4.Final connecting to a DB2 z/OS database (DSN12015) v12.015. I have the following dialect: import org.hibernate.dialect.DB2zDialect; import org.hibernate.dialect.pagination.LegacyDB2LimitHandler; import org.hibernate.dialect.pagination.LimitHandler; public class Db2zOsDialect extends DB2zDialect { @Override public SequenceInformationExtractor getSequenceInformationExtractor() { return LegacyDb2zOsSequenceInformationExtractor.INSTANCE; } @Override public LimitHandler getLimitHandler() { return LegacyDB2LimitHandler.INSTANCE; } } I have the following entity: @Table(name = "\"KEY\"")...

Among the control flow statements in Java, Switch is arguably the most delicate. Many programmers, even the most experienced, have difficulty mastering the different options of the Switch statement.