How to convert BigDecimal type to int type in Java

How to convert BigDecimal type to int type in Java

To convert a BigDecimal type to an int type in Java, use the intValue method.

BigDecimal bd = new BigDecimal("10");
int i = bd.intValue();

Conversely, to convert an int type to a BigDecimal type, use the valueOf method.

int i = 10;
BigDecimal bd = BigDecimal.valueOf(i);

Instead of new BigDecimal, valueOf is recommended, since it is cached in valueOf and is not always instantiated.

In contrast, new BigDecimal is always instantiated. It’s a small detail, but you have to be memory conscious in Java.

Accounting uses BigDecimal type

In accounting systems, BigDecimal is usually used.

However, BigDecimal may also become a circular decimal number, depending on how the instance is created.

Let’s try to divide by passing a double type to the constructor.

BigDecimal bd1 = new BigDecimal(1058.1);
BigDecimal bd2 = new BigDecimal(10);
System.out.println(bd1.divide(bd2)); // 105.809999999999990905052982270717620849609375

This is because the following is provided in the constructor of BigDecimal.

public BigDecimal(double val) {
  this(val,MathContext.UNLIMITED);
}

So, when creating an instance of BigDecimal, the argument should be enclosed in double quotation marks.

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