对于参数类型java.lang.Integer，java.lang.Integer，运算符<是未定义的

Question

public TreeNode find(Integer data){
    if (this.data == data)
        return this;
    if (data < this.data && leftChild != null)
        return leftChild.find(data);

    if (rightChild != null)
        return rightChild.find(data);
    return null;
}

Hi there!, so I've done some research about similar problems and tried most of the suggestions and still nothing. I would like to know how to solve this problem because I've been stuck for a couple of hours now.

Thank you in advance :)

Answer 1

A couple solutions:

• data.compareTo(this.data) < 0
• data.intValue() < this.data.intValue()

Generally speaking, you can't use < on boxed integers. Additionally, == will do the wrong thing, so you should be writing

if (this.data.equals(data))
    return this;

or

if (this.data.intValue() == data.intValue())