package org.hamcrest.number;

import org.hamcrest.Description;
import org.hamcrest.Matcher;
import org.hamcrest.TypeSafeMatcher;

import java.math.BigDecimal;
import java.math.MathContext;

public class BigDecimalCloseTo extends TypeSafeMatcher<BigDecimal> {

private final BigDecimal delta;
private final BigDecimal value;

public BigDecimalCloseTo(BigDecimal value, BigDecimal error) { = error;
this.value = value;

public boolean matchesSafely(BigDecimal item) {
return actualDelta(item).compareTo(BigDecimal.ZERO) <= 0;

public void describeMismatchSafely(BigDecimal item, Description mismatchDescription) {
.appendText(" differed by ")
.appendText(" more than delta ")

public void describeTo(Description description) {
description.appendText("a numeric value within ")
.appendText(" of ")

private BigDecimal actualDelta(BigDecimal item) {
return item.subtract(value, MathContext.DECIMAL128).abs().subtract(delta, MathContext.DECIMAL128).stripTrailingZeros();

* Creates a matcher of {@link java.math.BigDecimal}s that matches when an examined BigDecimal is equal
* to the specified <code>operand</code>, within a range of +/- <code>error</code>. The comparison for equality
* is done by BigDecimals {@link java.math.BigDecimal#compareTo(java.math.BigDecimal)} method.
* For example:
* <pre>assertThat(new BigDecimal("1.03"), is(closeTo(new BigDecimal("1.0"), new BigDecimal("0.03"))))</pre>

* @param operand
the expected value of matching BigDecimals
* @param error
the delta (+/-) within which matches will be allowed

public static Matcher<BigDecimal> closeTo(BigDecimal operand, BigDecimal error) {
return new BigDecimalCloseTo(operand, error);