Javaで四捨五入

gistfile1.java

package ironpeace;

import java.math.BigDecimal;

public class Sample {

  public static void main(String[] args) {
		System.out.println("1.234 -> " + round(1.234, 2)); // 1.23
		System.out.println("1.235 -> " + round(1.235, 2)); // 1.24
		System.out.println("1.236 -> " + round(1.236, 2)); // 1.24
	}
	
	public static double round(double val, int digit){
		BigDecimal bd = new BigDecimal(val);
		return bd.setScale(digit, BigDecimal.ROUND_HALF_UP).doubleValue();
	}

}