Writting to multiple files using MultiResourceItemWriter

In this post of Spring Batch, I will explain how to write the records read, to multiple files instead of one. We take the help of MultiResourceItemWriter, it writes to multiple file and suffixes the output fileNames with an index. For example if the file name to be created, is DemoData.txt and two files are…… Continue reading Writting to multiple files using MultiResourceItemWriter

Filtering items using ItemProcessor

In Spring Batch, items are read from the source using reader and written to destination using a writer. Sometimes, we need to add business logic between the reader and writer for the following purpose1) Filtering an item2) Converting an item read from one format to another before written to the destination3) Modify the item read…… Continue reading Filtering items using ItemProcessor

Combining two or more Consumer Functional Interface

In this post I will explain how to combine two or more Consumer Functional interface implementations. Consumer Functional interface has a default method “andThen”, which combines two Consumer Functional interface implementations. The method signature is as shown below default Consumer andThen(Consumer after) The way two Consumer implementations are combined using “andThen” method is as shown…… Continue reading Combining two or more Consumer Functional Interface

Map with Composite key

In Maps we always use one key object to uniquely identify an entry. We never combined a collection of keys to create one composite key and use it to uniquely identify an entry. But with help of MultiKey class available in Apache Common Collections framework, we can create a composite key to uniquely identify an…… Continue reading Map with Composite key

Sorting arrays using Comparator

This post explains how to sort arrays using comparator with an example. The java jdk provides Arrays class, which has a static method named “sort”. This method takes two arguments 1) the array to be sorted 2) Comparator which contains the logic to sort the array Below is the example which sort cards based on…… Continue reading Sorting arrays using Comparator