three decimal places in java code example

Example 1: decimal up to 6 places in java

double num = 1.34567;
System.out.format("%.4f", num);

Example 2: specify decimal places java

double test = 12.15;
DecimalFormat df = new DecimalFormat("#.0");
System.out.println(df.format(test)); // Console: 12.2
// # - prints a digit if provided, nothing otherwise
// . - indicates where to put the decimal seperator
// 0 - prints a digit if provided, 0 otherwise