two decimal palces in java code example

Example 1: 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

Example 2: java 2 decimals

double res = Math.round(a * 100) / 100;