Blogarama: The Oldest Blog Directory

INFO: Marking servlet [dad-frontController] as unavailableOct 22, 2021 6:31:27 PM org.apache.catalina.core.StandardContext loadOnStartupSEVERE: Servlet [dad-frontController] in web applicati… Read More

In our first Blog of this series we discussed about troubleshooting common errors which may occur while executing a Java MapReduce program ( see part 1 ). In this blog, we wil… Read More

As per Java language specification (https://docs.oracle.com/javase/specs/jls/se7/html/jls-12.html#jls-12.4.1),   1. A class or interface type T will be initialized immediately before t… Read More

Realizar un programa que le permita al usuario ingresar una serie de datos de un libro como el nombre del autor, el titulo, el precio y código. El programa deberá mostrar un me… Read More

The error message clearly says that the Java runtime is not able to find a class called ServletContainer for the Jersey library. This is the Servlet class you have specified in the… Read More

In this post, I am going to explain how to create, insert and query the table using JDBC.   Prerequisite Setup Postgresql.   Dependencies useddependency>groupId>org.postgresq… Read More

Introduction to LogstashEncoder LogstashEncoder helps get the functionality to log back the layouts, encoders, and the appenders in JSON format inside the logs. It also allows doing so for… Read More

In this article we’ll see what is java.lang.ClassNotFoundException and how to resolve ClassNotFoundException in Java. ClassNotFoundException in JavaClassNotFoundException is a child c… Read More

In this article we’ll see what is java.lang.ClassCastException and how to resolve ClassCastException in Java. ClassCastException in JavaClassCastException is thrown in a Java applica… Read More

Array in Java is also a class so many of the methods in java.lang.Class may be used with the array. Refer reflection in java – class to know more about the methods in Class.Reflection… Read More

When you serialize an object in Java it is converted to byte stream and object is reconstituted using that byte stream during the process of deserialization. Sometimes this extraneous behavi… Read More

If you ever implemented Serializable interface in Java then you would have seen the warning “The serializable class XXX does not declare a static final serialVersionUID field of t… Read More

Similar to reflection API for methods, there is also reflection API to get information about the constructors of a class. Using java.lang.reflect.Constructor class in Java reflection API y… Read More

In the post Serialization in Java it has already been discussed that serialization is the mechanism by which any object can be converted to byte stream. By default all of the object vari… Read More

Serialization in Java provides a pretty good default implementation for serializing and deserializing an object. All you need to do is to implement Serializable interface and the whole pro… Read More

How to Create Object in JavaThe object is a basic building block of an OOPslanguage. In Java, we cannot execute any program without creating an object. There is vari… Read More

Object serialization is the mechanism of converting object into byte stream. Where as the reverse process of recreating the object from those serialized bytes is known as deserialization. I… Read More

Follow below step-by-step procedure to connect to H2 database using Hibernate.   Step 1: Create new maven project ‘hibernate-h2-hello-world’.   Step 2: Update pom.xml w… Read More

Step 1: Create new maven project ‘hibernate-postgres-hello-world’.   Step 2: Update pom.xml with maven dependencies.   pom.xmlproject xmlns="http://maven.apache.org/POM… Read More

In this post, I am going to explain how to map an entity that contain embedded properties to a single database table using Embedded and Embeddable annotation.   For example, I have a co… Read More

Using @AttributeOverrides and @AttributeOverride anotations, we can override the column properties of embedded type. Example@Embedded@AttributeOverrides({@AttributeOverride( name = "firstNa… Read More

Your credit card has a limit, and if you spend over that, your purchase may be declined. This concept of exceeding limits to receive a negative response is not specific to just credit car… Read More

Value type represents a piece of data in the entity, which do not define its own life cycle.   Value types are categorized into three categories. a.   Basic types b. &nbs… Read More

JDBC API provides a set of interfaces and classes for connecting to DB, creating SQL statement, executing created SQL statement in database, returning the results and processing that Result… Read More

DatabaseMetaData in Java, which resides in java.sql package, provides information about the database (DB meta data) you are connected to.Using the methods provided by Java DatabaseMetaData… Read More

In the post Java JDBC Steps to Connect to DB we have already seen a complete example using the interfaces Driver, Connection, Statement and ResultSet provided by the JDBC API. In this post… Read More

In the post Statement interface in Java we have already seen how you can create a Statement using connection object and execute SQL statements. One problem though is that Statement interfac… Read More

In the post Statement Interface in Java-JDBC and PreparedStatement Interface in Java-JDBC we have already seen how you can use Statement to execute static SQL statements and PreparedStateme… Read More

What is Exception Handling in Java?Exception handling in java help us in reducing exceptions and helps in recovering from exceptions. It is one of the powerful mechanisms of java language to… Read More

Reflection in Java-class gives a good idea about how class is an entry point to all the Reflection APIs. Once you have Class object you can get information about members of the class fields… Read More

Hibernate map class references to VARCHAR type.   Example// mapped as VARCHARprivate Class> clazz; Follow below step-by-step procedure to build complete working appl… Read More

Java Exception Handling – A Complete Reference to Java ExceptionsWhat is meant by exception handling?Errors arise unexpectedly and can result in disrupting the normal flow of execution… Read More

Hibernate maps Currency references to VARCHAR JDBC type.// mapped as VARCHARprivate Currency currency;  Find the below working application.   Step 1: Create new ma… Read More

Before going into the differences between checked and unchecked exceptions in Java let's first see what these two types of exceptions are. Table of contentsChecked Exception in Java Check… Read More

If underlying database support UUID type, then Hibernate maps the property to SQL type UUID. If underlying database do not have UUID type, then it is mapped to JDBC BINARY type.   Can I… Read More

Hibernate map Local references to JDBC VARCHAR type.// mapped as VARCHARprivate Locale locale;  Find the below working application.   Step 1: Create new maven proj… Read More

If underlying database support INET data type, then Hibernate will map InetAddress variable to INET type, else it is mapped to JDBC BINARY type.   Example private InetAddress inetAddres… Read More

In this post, I am going to explain how to generate UUIDs as primary keys.   Using JPA 3.1 From JPA 3.1 onwards, by setting the generated value strategy to 'GenerationT… Read More

The term “serialization” describes the Java idea of encoding an object’s state as a sequence of bytes. All of the object’s d… Read More

This post provides detail about JDBC transaction management with examples for starting a transaction in JDBC, committing and rolling back a transaction, setting savepoint for transaction ro… Read More

If you have a large number of similar queries it is better to process them in a batch rather than as individual queries. Processing them as a batch provides better performance as you send a… Read More

highlight: a11y-dark theme: condensed-night-purple Maven Jar冲突时我们在开发过程中最常见并且… Read More

User-defined Custom Exception in JavaAn exception is an issue (run time error) that occurred during the execution of a program. When an exception occurred the program gets terminated abruptl… Read More

Problem: You are getting java.lang.ClassNotFoundException exception complaining that Spring's DispatcherServlet class is not available in the classpath. This error is coming while running a… Read More

Introduction According to the TIOBE index, Java is one of the most popular programming languages globally.90% of companies on the Fortune 500 list use Java programming language. Java is evol… Read More

1、前言 1.1 现象（问题） ​微服务架构项目落地过程中ᦁ… Read More

Java exception handling can be challenging. Which Java exceptions ought to be caught, and which ones ought to be thrown again? And which exceptions… Read More

Class VirtualMachineError in JavaJava virtual machine is an abstract computer, on which all Java coding runs. Java often refers to a java programmin… Read More

PostgreSQL is one of the most popular open-source relational database management systems. It is known for its robustness, scalability, and reliability. Java, on the other hand, is a popular… Read More

Max BeckersFollowBetter Programming--ListenShareSpring Boot 3 comes with support for native images. This is the part for GraalVM. GraalVM transitions from a just-in-time (JIT) compiler built… Read More

Quick Summary: Creational design patterns in Java encompass Singleton, Factory Method, Abstract Factory, Builder, and Prototype. These patterns provide flexible and structured approaches to… Read More

By Rafael del Nero, Java Developer, InfoWorld |Tease your mind and test your learning, with these quick introductions to challenging concepts in Java programming.Java class loaders are a… Read More

In this blog, we will guide you step by step through the basics of Java web development. From understanding the rudiments of Java to building dynamic web applications, this blog will highlig… Read More

Exception Handling In Java Programming Online Course Exception handling is a crucial aspect of Java programming Online Course that allows you to deal with unexpected or exceptional situat… Read More

Microsoft, salah satu perusahaan teknologi raksasa di dunia, baru-baru ini mengumumkan bahwa Bing AI, alat bantu percakapan yang menggunakan kecerdasan buatan, kini resmi didukung di browser… Read More

What is ClassNotFoundException in Java ClassNotFoundException is one of Java nightmare every Java developer face in there day to day life. java.lang.NoClassDefFoundError and java.lang.Clas… Read More

The java.lang.UnsupportedClassVersionError  is a quite common error after NoClassDefFoundError or ClassNotFoundException they all seems to related to class files but they all are diff… Read More

Sign upSign InSign upSign InHabiba GamilFollowLevel Up Coding--ListenShareI like to think of programming paradigms as territories. From imperative to declarative programming, each territory… Read More

Posted on Oct 9 Production traffic replication is a technique used to record traffic in production environment, and replaying it in another. It is also considered the best s… Read More

Imagine, you are developing Java software and suddenly you encounter errors. Where could have possibly gone wrong? There are many types of errors that you will encounter while develo… Read More