Handling of java floating point [Note] while reading the reference book

0.7 + 0.1 = 0.8, but if you let the computer calculate it, an error will occur. I will omit the reason why it comes out (** see below **). https://www.php.net/manual/ja/language.types.float.php

The reference book uses ** Big Decimal ** to deal with it.


package demojava.demo5;

import java.math.BigDecimal;

public class Demo5 {
	public static void main(String [] args) {
		double test1 = 0.0;
		test1 = 0.7 + 0.1;
		System.out.println("test1 = " + test1);

	public static void test2() {
		BigDecimal val1 = new BigDecimal("0.7");
		BigDecimal val2 = new BigDecimal("0.1");
		BigDecimal val = val1.add(val2);
		System.out.println("test2 = " + val);

Execution result


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