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How Reverse a String in C#

See how to reverse a string. public static string ReverseString( string input) { char[] array = input.ToCharArray(); Array.Reverse(array); return new string(array); }Console.WriteLine(ReverseString(“devx”)); Related Posts Turbulence injures 12 on Qatar Airways

Working with ArrayList Operations

ArrayList has an overloaded method that accepts a string, as well as an Integer, as an argument. The remove method can remove elements based on the string, along with the

TCP: out of memory — consider tuning tcp_mem

Recently we experienced an interesting production problem. This application was running on multiple AWS EC2 instances behind Elastic Load Balancer. Application was running on GNU/Linux OS, Java 8, Tomcat 8 application server. All of sudden one of the application instances became unresponsive. All other application instances were handling the traffic properly. Whenever HTTP request was sent to this application instance from the browser, we were getting following response to be printed on the browser. Related Posts Chaining Null Comparisons with the ?? Operatorthis is test headerManor Lords publisher defends early access strategyHow To Scan QR Codes On AndroidMysterious Google Algorithm Update Sparks SEO

Discovering the Reason for Poor Query Performance

What can cause poor performance of a query? Any or a combination of these: No indexes exist for the tables Unnecessarily complicated joins Excess usage of cursors Excess usage of

Java Support for the Hijri Calendar

The Hijri calendar system is somewhat different from the Gregorian calendar. This example does not discuss the complete Hijri calendar. This is only to educate you regarding the existence of

Tip: Java Support for the Hijrah Calendar

The Hijri calendar system is somewhat different from the Gregorian calendar. This example does not discuss the complete Hijri calendar. This is only to educate you regarding the existence of

Usage of the Repository Factory Class

Spring Data provide a class named RepositoryFactorySupport. Via this class we can access any repository, as in the following example: RepositoryFactorySupport factory = … // code that instantiate the factory;CustomerRepository

Format the Currency for a Culture in C#

Use the CultureInfo class to format values based on a culture. See below for an example: public static void Main() { decimal inputValue = 233; CultureInfo currentCulture = new CultureInfo(“en-US”);

Variable Arguments in Java

Moving away from the age old way of fixed arguments, Java supports variable arguments. The code sample below illustrates variable arguments. If the method has multiple arguments, it is mandatory

Types of Indexes that Exist in SQL

What types of indexes are there? Answer: Clustered Sort and store data based on key values Non-clustered Each key is a pointer to the data row Related Posts Sapio Sciences

Using REGEX and Patterns in Java

Java has a very powerful library for REGEX. A very basic usage of REGEX is being presented in the code snippet below and we can improve on this to develop

Disable Open Session in View in a Spring Boot Application

For disabling OSIV, we need to set up spring.jpa.open-in-view in application.properties as follows: spring.jpa.open-in-view=false Related Posts Survey: 40% of Americans Have No Confidence in IoT Security MeasuresTipflation: Pandemic sparks surge

Countdown Timer Function in C#

See how to use this function in C# to discover how many more days are left in a given countdown. DateTime startDate = DateTime.Now;DateTime endDate = DateTime.Now.AddDays(-1);TimeSpan t = startDate

Getting the Last ID in MySQL

MySQL supports AUTO_INCREMENT column types where the value of a particular column can be auto incremented as, and when, the records are inserted. Many instances would need the last value

Three Ways to Limit Your Results in SQL Server 2016

The query below uses TOP to select the TOP 3 students: TOPSELECT TOP 3 *FROM Students; The code below uses LIMIT to only show three records: SELECT StudentName, StudentPercentageFROM StudentsLIMIT

Java StringWriter

StringWriter is similar to StringBuffer, which can collect a host of string values and work with the data. We will explore writing a porting of a given string. Code sample:

Convert a Date to ISO 8601 Format in C#

Please see below for an example of how to convert a date time to ISO 8601 format. string isoFormatDateString = dateTimeObject.ToUniversalTime().ToString(“s”) + “Z”; Related Posts From cart to cafes: Nitro

Using the WEEKOFYEAR Function in MySQL

MySQL has abundant functions that support a multitude of application needs. Here, we shall use some Calendar functionality to find in which week a given date belongs. Samples: Considering the

Async Query Results

Repository queries can be executed asynchronously using @Async annotation. The result can be a Future, CompletableFuture and ListenableFuture. The method will return immediately upon invocation: @asyncFuture findByName(String name);@asyncCompletableFuture findByName(String name);@asyncListenableFuture

Creating User Defined Functions

There are many instances in which you might repeatedly use some functionality. It would be handy if you were allowed to create a function that could be used as, and

T-SQL Performance Tip: Stored Procedure Names

Avoid prefixing your Stored Procedure names with sp_. SQL Server first checks in the master database even when the Schema name is provided. Related Posts Augment Agile Programming with Engineering

Return a MappingJacksonValue from a REST Controller

A proof of concept can be seen below: @GetMapping(“…”)public MappingJacksonValue fooMethod(…) throws JsonProcessingException { List foos = …; MappingJacksonValue wrapper = new MappingJacksonValue(fooa); … return wrapper;} Related Posts How To

Using Symbolic Links in Java

Symbolic links are a useful entity, with which you can introduce some kind of encapsulation. The Symbolic link can be created in a secure environment (ex: DMZ) where users can

Convert a String to a Byte Array

Explore how to convert a string to a byte array. String stringToBeConverted = ” ? ” ;int stringLength = stringToBeConverted.Length;byte[] bytes = new byte[stringLength / 2];for (int counter = 0;

Unwrapping a Session from EntityManager

When we need access to a Hibernate Session, we have to unwrap it from the current EntityManager via the unwrap() method as follows: // Spring and Java EE EntityManager em

T-SQL Performance Tip: NOT IN vs NOT EXISTS

Avoid using NOT IN whilst comparing nullable columns. Use NOT EXISTS instead. When NOT IN is used in a query, SQL Server compares each result to null (even if no

Use MySQL for Calculations

At times, when you want to compute the result of a mathematical formula, you can use MySQL to do the task. It is a great tool for this. Here are