title: Writable Shared Memory in Apache Spark
body: <p>I am working on a project of Twitter Data Analysis using Apache Spark with Java and Cassandra for NoSQL databases. </p>
  
  <p>In the project I am working I want to maintain a arraylist of linkedlist(will use Java in built Arraylist and Linkedlist) which is common to all mapper nodes. I mean, if one mapper writes some data into arraylist it should be reflected to all other mapper nodes.</p>
  
  <p>I am aware of broadcast shared variable, but that is read only shared variable, what I want is shared writable dataframe where changes by one mapper should be reflected in all.</p>
  
  <p>Any advice on how to achieve this in apache spark with Java will be of great help.</p>
  
  <p>Thanks in advance</p>