Category: Java

  • Different ways to invoke shell commands in Java

    Learn how to invoke sell command using Java.

  • Spring Boot Flyway DB Migration Integration Example

    Spring Boot Flyway DB Migration Integration Example

    Learn how to use Flyway db migration toll with spring boot projects.

  • Spring Boot Unit and Integration Test With Testcontainers

    Spring Boot Unit and Integration Test With Testcontainers

    Testcontainers is a very elegant, clean library to write Unit and Integration tests using docker containers, which provides almost real stacks for testing Java Spring applications.

  • Java Example to Push Website Access Logs to Cassandra DB

    Java Example to Push Website Access Logs to Cassandra DB

    Cassandra DB is one of the leading NoSQL database system as it can be very easily configured in scalable cluster in bot on-prime and cloud environment. Most of the leading cloud providers now providing it as managed or serverless service. It is a column based NoSQL and provides very fast write operation. Cassandra has drivers […]

  • Using AWS Credentials with Service Client in Java Spring

    AWS provides Java SDK to make requests to Amazon Web services. Using SDK we can make requests and perform the different operations of AWS services. We need to provide AWS credentials while making requests, by default SDK tries to use the default credentials configured on the host. There are various ways to provide credentials to […]

  • Sorting Object By one or More Properties in Java

    While working with arrays or lists or any other collection in java, many times we need to sort elements. For primitives and strings, it can be straightforward. But for customer objects, we need to write Comparator or implement a Comparable interface. If you are dealing with objects without Comparable interface or you need to perform […]

  • Most Efficient Way to Search Element in Java Array

    Using core java we can search an element in an array in many ways. For searching in arrays of primitive or Objects, some methods are common for both and some can be used with in primitive type arrays. 1- For me most efficient method is using Arrays.binarySeach method. It provides an overloaded version for all […]

  • 8 Ways to Iterate Each Entry of Java Map

    Java collection framework has Map interface and several implementation classes like HashMap, LinkedHashMap, TreeMap, ConcurrentHashMap. Map one of the most used interface used to store and operate on key-value pairs. To iterate all entries of a Map, there are several ways as given below. 1- Using foreach and entrySet method 2- Using map.forEach method 3- […]

  • Parsing String to Int in Java

    Converting a string number to int in java can be done using several ways. We can use the java Integer class pasrseInt and valueOf methods. We can create of util method to do this with exception handling. Integer num = Integer.valueOf(input);// orint num = Integer.parseInt(input);There is a slight difference between these methods: valueOf returns a […]

  • Best ways to create ArrayList from Array in Java

    Many times we need to create an ArrayList from arrays of objects in java. There are several ways to do this using core Java APIs or third-party open-source libs like guava. The easiest way to do this is by using the JDK Arrays class. Using JDK to convert array to ArrayList But the above one […]