gistfile1.txt

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.math.RoundingMode;
import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.text.NumberFormat;
import java.util.Locale;

public class UberTest {
    private static final Log log = LogFactory.getLog(UberTest.class);

    public static void main(String[] args) throws Exception {
        NumberFormat decimalFormat = new DecimalFormat("#0.00", new DecimalFormatSymbols(Locale.ENGLISH));

        double d0 = 3.124;
        double d1 = 3.125;

        log.info(decimalFormat.format(d0));
        log.info(decimalFormat.format(d1));

        log.info("====");

        decimalFormat.setRoundingMode(RoundingMode.HALF_UP);

        log.info(decimalFormat.format(d0));
        log.info(decimalFormat.format(d1));
    }
}

2017-04-14 11:49:31,090 INFO  [UberTest] 3.12
2017-04-14 11:49:31,090 INFO  [UberTest] 3.12
2017-04-14 11:49:31,090 INFO  [UberTest] ====
2017-04-14 11:49:31,098 INFO  [UberTest] 3,12
2017-04-14 11:49:31,098 INFO  [UberTest] 3,13