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package org.ruoxue.java_147.functional.bifunction;

import static org.junit.Assert.*;

import java.util.Locale;
import java.util.Objects;
import java.util.function.BiFunction;

import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;
import org.apache.commons.lang3.builder.ToStringBuilder;
import org.apache.commons.lang3.builder.ToStringStyle;
import org.junit.Test;

import lombok.Builder;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

public class BiFunctionFunctionalTest {

	@NoArgsConstructor
	@Getter
	@Setter
	@Builder
	public static class Food {
		private String name;
		private double quantity;
		private int type;

		public Food(String name, double quantity, int type) {
			this.name = name;
			this.quantity = quantity;
			this.type = type;
		}

		public String toString() {
			ToStringBuilder builder = new ToStringBuilder(this, ToStringStyle.JSON_STYLE);
			builder.appendSuper(super.toString());
			builder.append("name", name);
			builder.append("quantity", quantity);
			builder.append("type", type);
			return builder.toString();
		}

		public boolean equals(Object object) {
			if (!(object instanceof Food)) {
				return false;
			}
			if (this == object) {
				return true;
			}
			Food other = (Food) object;
			return new EqualsBuilder().append(getName(), other.getName()).isEquals();
		}

		public int hashCode() {
			return new HashCodeBuilder().append(getName()).toHashCode();
		}
	}

	@Test
	public void methodReference() {
		BiFunction<String, String, Locale> locale = Locale::new;
		Locale result = locale.apply("zh", "TW");
		System.out.println(result);
		assertNotNull(result);

		BiFunction<String, String, String> concat = String::concat;
		String stringResult = concat.apply("Bacon", "Ham");
		System.out.println(stringResult);
		assertNotNull(stringResult);

		BiFunction<Integer, Integer, Integer> max = Integer::max;
		int intResult = max.apply(1, 10);
		System.out.println(intResult);
		assertEquals(10, intResult);

		BiFunction<String, String, Boolean> equals = Objects::equals;
		boolean booleanResult = equals.apply("Bacon", "Ham");
		System.out.println(booleanResult);
		assertFalse(booleanResult);
	}

	public static double calc(double d1, double d2, BiFunction<Double, Double, Double> biFunction) {
		return biFunction.apply(d1, d2);
	}

	public static double foodCalc(Food o1, Food o2, BiFunction<Food, Food, Double> biFunction) {
		return biFunction.apply(o1, o2);
	}

	@Test
	public void methodParameter() {
		double result = calc(1d, 10d, (d1, d2) -> d1 + d2);
		System.out.println(result);
		assertEquals(11d, result, 2);

		result = foodCalc(new Food("Bacon", 1, 1), new Food("Ham", 2, 1), (o1, o2) -> o1.quantity + o2.quantity);
		System.out.println(result);
		assertEquals(3d, result, 2);
	}
}