how to read a file, line by line, without load all file on memory

[Augusto Vilarim]

Hi Everyone!

First of all, sorry about my poor english. 

Well, i´m trying to read and parse a huge file with beanIO, and my concern is about memory allocation. When i do my brenchmark here, i notice that i dont need to load all beans on memory, i just need one single line per validation, there is some way to load one line per loop in memory, to avoid high memory usage? 

Thanks a lot!

[Paul Rule]

BeanIO doesn't need to read the whole file into memory - you just read one 'object'/line at a time.

If you look at the sample in the documentation:

 http://www.beanio.org/2.1/docs/reference/index.html#MyFirstStream

BeanReader in = factory.createReader("employeeFile", new File("employee.csv"));
        Employee employee;
        while ((employee = (Employee) in.read()) != null) {
            // process the employee...
        }
        in.close();

The line

  employee = (Employee) in.read()

is just reading (streaming) one line at a time AFAIK.

If you read a massive file in this manner, hopefully you wont' see any significant memory usage.