Java large datastructure for storing a matrix

Question

I need to store a 2d matrix containing zip codes and the distance in km between each one of them. My client has an application that calculates the distances which are then s

Answer 1

Can you simply boost the memory available to the JVM ?

java -Xmx512m ...

By default the maximum memory configuration is 64Mb. Some more tuning tips here. If you can do this then you can keep the data in-process and maximise the performance (i.e. you don't need to calculate on the fly).