Using DecimalFormat in java/groovy

DecimalFormatExample.java

import java.text.DecimalFormat;
...
DecimalFormat df = new DecimalFormat("###,##0.00");
df.format(number);

// in the format string,
// # -> shows Digit if present else blank
// 0 -> shows Digit if present else 0
// details at :  http://docs.oracle.com/javase/6/docs/api/java/text/DecimalFormat.html