在Java中创建默认构造函数

Question

我需要创建一个默认的构造,其中规定的方法name为空字符串,并将两路credits和contactHours为零.怎么做？谢谢,彼得.

Answer 1

方法没有构造函数......类.例如:

public class Dummy
{
    private int credits;
    private int contactHours;
    private String name;

    public Dummy()
    {
        name = "";
        credits = 0;
        contactHours = 0;
    }

    // More stuff here, e.g. property accessors
}

您实际上不必设置credits或contactHours,因为int字段默认为0,无论如何.

您可能想要至少一个带有初始值的构造函数 - 在这种情况下,您的无参数构造函数可以委托给它:

public class Dummy
{
    private String name;
    private int credits;
    private int contactHours;

    public Dummy()
    {
        this("", 0, 0);
    }

    public Dummy(String name, int credits, int contactHours)
    {
        this.name = name;
        this.credits = credits;
        this.contactHours = contactHours;
    }

    // More stuff here, e.g. property accessors
}