I am using the Xstream freamwork to read a lot of files in a batch operation. I use a custom converter Xstream to read some properties of my Xml file, but when I changed my application to process xml files using Multithreading, I saw my application consume all avaliable memory in the JVM. Using Jvisualvm and isolating some parts of my code I find the problem. I call the methods flush and close on HierarchicalStreamWriter and the problem wasn├?┬┤t solved. What Am I doing some wrong?