在同一个类中使用比较函数时如何实现比较器[关闭]

Question

如果一个类实现了比较器，我们如何定义比较函数？

public int compare(classname c1, classname c2) {
    // c1 has to be this.how can we use it?
}

Answer 1

您使用 java 泛型，内置于 Comparator 接口。

public class MyClass implements Comparator<MyClass>

Answer 2

public int compare(classname c1, classname c2) {
    if (cl.something > c2.something)
        return 1;
    else if (c1.something == c2.something)
        return 0;
    else
        return -1;
}

编辑：可比较

public class classname implements Comparable<classname>{
    int something;

    public int compareTo(classname c2){
        if (this.something > c2.something)
            return 1;
        else if (this.something == c2.something)
            return 0;
        else
            return -1;
    }
}