如何处理接受字符串或整数的通用 Java 类的比较运算符
我有兴趣使用可以处理 String 或 Integer 数据类型的通用 Java 类.我想使用比较运算符，但它似乎有一个编译错误:
I am interested in using a generic Java class which can handle String or Integer data type. I'd like to utilize the comparison operator, but it appears to have a compile error:
运算符 <不能用于通用 T
Operator < cannot be used on generic
T
对于T，如何使用比较运算符(如<、>、= 等)?(假设 T 是 Number 或 String).
How can I achieve using comparison operators such as <, >, =, etc. for T? (Assuming T is Number or String).
public class Node<T> {
public T value;
public Node(){
}
public void testCompare(T anotherValue) {
if(value == anotherValue)
System.out.println("equal");
else if(value < anotherValue)
System.out.println("less");
else if(value > anotherValue)
System.out.println("greater");
}
}
}
推荐答案
使用可比界面:
public class Node<T extends Comparable<T>> {
public T value;
public Node() {
}
public void testCompare(T anotherValue) {
int cmp = value.compareTo(anotherValue);
if (cmp == 0)
System.out.println("equal");
else if (cmp < 0)
System.out.println("less");
else if (cmp > 0)
System.out.println("greater");
}
}
由String、Integer、Long、Double、Date实现和许多其他课程.
It's implemented by String, Integer, Long, Double, Date and many other classes.