无法创建BeerBarrel类并将其赋值给变量

Question

我编写了一个BeerBarrel类，但是新BeerBarrels的创建似乎不能正常工作。我真的不明白这个错误。

public class BeerBarrel extends FluidContainer{
private static int totalBarrels = 0, totalLiters = 0;

private BeerBarrel(String type, int liter) {
    naming = type;
    totalFluid_in_liter = liter;
    totalBarrels++;
    this.fluidContainerId = totalBarrels;
    totalLiters += liter;
}

public void tap(int liter) {
    this.totalFluid_in_liter -= liter;
    totalLiters -= liter;
}

public static int getTotalBarrels() {
    return totalBarrels;
}

public static int getTotalLiters() {
    return totalLiters;
}
}

以下是问题所在：

public void run() {

BeerBarrel bf1 = new BeerBarrel("Pils", 80);
BeerBarrel bf2 = new BeerBarrel("Alt", 100);

BeerBarrel bf3 = new BeerBarrel("Koelsch", 50);

Answer 1

问题是BeerBarrel中的构造函数是私有的。不能从类外部访问私有构造函数。解决方案是：

public BeerBarrel(String type, int liter) {​​​​​​
    naming = type;
    totalFluid_in_liter = liter;
    totalBarrels++;
    this.fluidContainerId = totalBarrels;
    totalLiters += liter;
}​​​​​​