referentialtransparency.java

高质量Java程序设计 源代码

package net.betterjava.design.sideeffect;

public class ReferentialTransparency {

	private int value = 0;

	public void plusPlus() {
		value++;
	}

	public int getValue() {
		return value;
	}

	public void multiply(int i) {
		value = value * i;
	}

	public void plus(int i) {
		value = value + i;
	}

	public String toString() {
		return String.valueOf(value);
	}

	public static void main(String[] args) {
		ReferentialTransparency i = new ReferentialTransparency();
		ReferentialTransparency j = new ReferentialTransparency();
		i.plusPlus();
		i.multiply(2);
		System.out.println(i.getValue());
		j.plusPlus();
		System.out.println(j.getValue() + j.getValue());
	}
}