feat(devkit-core): added ChainedCalcUtil
This commit is contained in:
Zihlu Wang
@@ -0,0 +1,352 @@
|
||||
/*
|
||||
* Copyright (C) 2023 CodeCraftersCN.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
*
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package cn.org.codecrafters.devutils;
|
||||
|
||||
import java.math.BigDecimal;
|
||||
import java.math.RoundingMode;
|
||||
import java.util.Objects;
|
||||
import java.util.function.BiFunction;
|
||||
import java.util.function.Function;
|
||||
|
||||
/**
|
||||
* Utility class for chained high-precision calculations using BigDecimal.
|
||||
* <p>
|
||||
* The ChainedCalcUtil class provides a convenient way to perform chained
|
||||
* high-precision calculations using BigDecimal. It allows users to perform
|
||||
* mathematical operations such as addition, subtraction, multiplication,
|
||||
* and division with customizable precision and scale. By using this utility
|
||||
* class, developers can achieve accurate results and avoid precision loss
|
||||
* in their calculations.
|
||||
* <p>
|
||||
* <b>Usage:</b>
|
||||
* <pre>
|
||||
* // Perform addition: 3 + 4
|
||||
* BigDecimal result1 = ChainedCalcUtil.startWith(3)
|
||||
* .add(4)
|
||||
* .getValue();
|
||||
*
|
||||
* // Perform subtraction: 4 - 2
|
||||
* BigDecimal result2 = ChainedCalcUtil.startWith(4)
|
||||
* .subtract(2)
|
||||
* .getValue();
|
||||
*
|
||||
* // Perform multiplication: 3 * 6
|
||||
* BigDecimal result3 = ChainedCalcUtil.startWith(3)
|
||||
* .multiply(6)
|
||||
* .getValue();
|
||||
*
|
||||
* // Perform division: 6 ÷ 2
|
||||
* BigDecimal result4 = ChainedCalcUtil.startWith(6)
|
||||
* .divide(2)
|
||||
* .getValue();
|
||||
*
|
||||
* // Perform division with specified scale: 13 ÷ 7 with a scale of 2
|
||||
* BigDecimal result5 = ChainedCalcUtil.startWith(13)
|
||||
* .divideWithScale(7, 2)
|
||||
* .getValue();
|
||||
*
|
||||
* // Get int, long, or double results
|
||||
* int intResult = ChainedCalcUtil.startWith(3)
|
||||
* .add(4)
|
||||
* .getInteger();
|
||||
*
|
||||
* long longResult = ChainedCalcUtil.startWith(4)
|
||||
* .subtract(2)
|
||||
* .getLong();
|
||||
*
|
||||
* double doubleResult = ChainedCalcUtil.startWith(6)
|
||||
* .divide(2)
|
||||
* .getDouble();
|
||||
*
|
||||
* // Get BigDecimal result with specified scale
|
||||
* BigDecimal result6 = ChainedCalcUtil.startWith(13)
|
||||
* .divide(7)
|
||||
* .getValue(2);
|
||||
* </pre>
|
||||
* The above expressions perform various mathematical calculations using the ChainedCalcUtil class.
|
||||
* <p>
|
||||
* <b>Note:</b>
|
||||
* The ChainedCalcUtil class internally uses BigDecimal to handle high-precision calculations. It is important to note
|
||||
* that BigDecimal operations can be memory-intensive and may have performance implications for extremely large numbers
|
||||
* or complex calculations.
|
||||
*
|
||||
* @author sunzsh
|
||||
* @version 1.0.0
|
||||
* @see java.math.BigDecimal
|
||||
* @since 9 Jul 2023
|
||||
*/
|
||||
public final class ChainedCalcUtil {
|
||||
|
||||
private BigDecimal value;
|
||||
|
||||
/**
|
||||
* Creates a ChainedCalcUtil instance with the specified initial value.
|
||||
*
|
||||
* @param value the initial value for the calculation
|
||||
*/
|
||||
private ChainedCalcUtil(Number value) {
|
||||
this.value = convertBigDecimal(value, null);
|
||||
}
|
||||
|
||||
/**
|
||||
* Starts a chained calculation with the specified initial value.
|
||||
*
|
||||
* @param value the initial value for the calculation
|
||||
* @return a ChainedCalcUtil instance for performing chained calculations
|
||||
*/
|
||||
public static ChainedCalcUtil startWith(Number value) {
|
||||
return new ChainedCalcUtil(value);
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds the specified value to the current value.
|
||||
*
|
||||
* @param other the value to be added
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil add(Number other) {
|
||||
return operator(BigDecimal::add, other);
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds the specified value to the current value with a specified scale before the operation.
|
||||
*
|
||||
* @param other the value to be added
|
||||
* @param beforeOperateScale the scale to be applied before the operation
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil add(Number other, Integer beforeOperateScale) {
|
||||
return operator(BigDecimal::add, other, beforeOperateScale);
|
||||
}
|
||||
|
||||
/**
|
||||
* Subtracts the specified value from the current value.
|
||||
*
|
||||
* @param other the value to be subtracted
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil subtract(Number other) {
|
||||
return operator(BigDecimal::subtract, other);
|
||||
}
|
||||
|
||||
/**
|
||||
* Subtracts the specified value from the current value with a specified scale before the operation.
|
||||
*
|
||||
* @param other the value to be subtracted
|
||||
* @param beforeOperateScale the scale to be applied before the operation
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil subtract(Number other, Integer beforeOperateScale) {
|
||||
return operator(BigDecimal::subtract, other, beforeOperateScale);
|
||||
}
|
||||
|
||||
/**
|
||||
* Multiplies the current value by the specified value.
|
||||
*
|
||||
* @param other the value to be multiplied by
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil multiply(Number other) {
|
||||
return operator(BigDecimal::multiply, other);
|
||||
}
|
||||
|
||||
/**
|
||||
* Multiplies the current value by the specified value with a specified scale before the operation.
|
||||
*
|
||||
* @param other the value to be multiplied by
|
||||
* @param beforeOperateScale the scale to be applied before the operation
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil multiply(Number other, Integer beforeOperateScale) {
|
||||
return operator(BigDecimal::multiply, other, beforeOperateScale);
|
||||
}
|
||||
|
||||
/**
|
||||
* Divides the current value by the specified value.
|
||||
*
|
||||
* @param other the value to divide by
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil divide(Number other) {
|
||||
return operator(BigDecimal::divide, other);
|
||||
}
|
||||
|
||||
/**
|
||||
* Divides the current value by the specified value with a specified scale before the operation.
|
||||
*
|
||||
* @param other the value to divide by
|
||||
* @param beforeOperateScale the scale to be applied before the operation
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil divide(Number other, Integer beforeOperateScale) {
|
||||
return operator(BigDecimal::divide, other, beforeOperateScale);
|
||||
}
|
||||
|
||||
/**
|
||||
* Divides the current value by the specified value with a specified scale.
|
||||
*
|
||||
* @param other the value to divide by
|
||||
* @param scale the scale for the result
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil divideWithScale(Number other, Integer scale) {
|
||||
return baseOperator(otherValue ->
|
||||
this.value.divide(otherValue, scale, RoundingMode.HALF_UP), other, null);
|
||||
}
|
||||
|
||||
/**
|
||||
* Divides the current value by the specified value with a specified scale and a scale applied before the operation.
|
||||
*
|
||||
* @param other the value to divide by
|
||||
* @param scale the scale for the result
|
||||
* @param beforeOperateScale the scale to be applied before the operation
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
public ChainedCalcUtil divideWithScale(Number other, Integer scale, Integer beforeOperateScale) {
|
||||
return baseOperator(otherValue -> this.value.divide(otherValue, scale, RoundingMode.HALF_UP), other, beforeOperateScale);
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the current value as a BigDecimal.
|
||||
*
|
||||
* @return the current value as a BigDecimal
|
||||
*/
|
||||
public BigDecimal getValue() {
|
||||
return value;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the current value as a BigDecimal with the specified scale.
|
||||
*
|
||||
* @param scale the scale for the result
|
||||
* @return the current value as a BigDecimal with the specified scale
|
||||
*/
|
||||
public BigDecimal getValue(int scale) {
|
||||
return value.setScale(scale, RoundingMode.HALF_UP);
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the current value as a Double.
|
||||
*
|
||||
* @return the current value as a Double
|
||||
*/
|
||||
public Double getDouble() {
|
||||
return getValue().doubleValue();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the current value as a Double with the specified scale.
|
||||
*
|
||||
* @param scale the scale for the result
|
||||
* @return the current value as a Double with the specified scale
|
||||
*/
|
||||
public Double getDouble(int scale) {
|
||||
return getValue(scale).doubleValue();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the current value as a Long.
|
||||
*
|
||||
* @return the current value as a Long
|
||||
*/
|
||||
public Long getLong() {
|
||||
return getValue().longValue();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the current value as an Integer.
|
||||
*
|
||||
* @return the current value as an Integer
|
||||
*/
|
||||
public Integer getInteger() {
|
||||
return getValue().intValue();
|
||||
}
|
||||
|
||||
/**
|
||||
* Applies the specified operator function to the current value and another value.
|
||||
*
|
||||
* @param operator the operator function to apply
|
||||
* @param otherValue the value to apply the operator with
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
private ChainedCalcUtil operator(BiFunction<BigDecimal, BigDecimal, BigDecimal> operator, Object otherValue) {
|
||||
return operator(operator, otherValue, 9);
|
||||
}
|
||||
|
||||
/**
|
||||
* Applies the specified operator function to the current value and another value with a specified scale before the operation.
|
||||
*
|
||||
* @param operator the operator function to apply
|
||||
* @param other the value to apply the operator with
|
||||
* @param beforeOperateScale the scale to be applied before the operation, or null if not applicable
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
private ChainedCalcUtil operator(BiFunction<BigDecimal, BigDecimal, BigDecimal> operator, Object other, Integer beforeOperateScale) {
|
||||
return baseOperator((otherValue) -> operator.apply(this.value, otherValue), other, beforeOperateScale);
|
||||
}
|
||||
|
||||
/**
|
||||
* Applies the specified operator function to the current value and another value.
|
||||
*
|
||||
* @param operatorFunction the operator function to apply
|
||||
* @param anotherValue the value to apply the operator with
|
||||
* @param beforeOperateScale the scale to be applied before the operation, or null if not applicable
|
||||
* @return a ChainedCalcUtil instance with the updated value
|
||||
*/
|
||||
private synchronized ChainedCalcUtil baseOperator(Function<BigDecimal, BigDecimal> operatorFunction,
|
||||
Object anotherValue, Integer beforeOperateScale) {
|
||||
if (Objects.isNull(anotherValue)) {
|
||||
return this;
|
||||
}
|
||||
if (anotherValue instanceof ChainedCalcUtil) {
|
||||
this.value = operatorFunction.apply(((ChainedCalcUtil) anotherValue).getValue());
|
||||
return this;
|
||||
}
|
||||
this.value = operatorFunction.apply(convertBigDecimal(anotherValue, beforeOperateScale));
|
||||
return this;
|
||||
}
|
||||
|
||||
/**
|
||||
* Converts the specified value to a BigDecimal.
|
||||
*
|
||||
* @param value the value to convert
|
||||
* @param scale the scale to apply to the resulting BigDecimal, or null if not applicable
|
||||
* @return the converted BigDecimal value
|
||||
*/
|
||||
private BigDecimal convertBigDecimal(Object value, Integer scale) {
|
||||
if (Objects.isNull(value)) {
|
||||
return BigDecimal.ZERO;
|
||||
}
|
||||
BigDecimal res;
|
||||
if (value instanceof Number num) {
|
||||
res = BigDecimal.valueOf(num.doubleValue());
|
||||
} else {
|
||||
try {
|
||||
res = new BigDecimal(value.toString());
|
||||
} catch (NumberFormatException ignored) {
|
||||
return BigDecimal.ZERO;
|
||||
}
|
||||
}
|
||||
|
||||
if (Objects.nonNull(scale)) {
|
||||
return res.setScale(scale, RoundingMode.HALF_UP);
|
||||
}
|
||||
return res;
|
||||
}
|
||||
|
||||
}
|
||||
Reference in New Issue
Block a user