我们可以在 pojo 中有两个二传手吗？

Question

I have a setter that converts a string to byte[] and one simple setter which just sets the value. My question here is, is it a good practice to have two setters in a POJO? I can't find any workaround :(

Example:

byte[] a;

//Case 1: Where we recieve parameter as a string and convert it to byte array and set it to a; 
public void setA(String aString){
this.a=convertTobyteArray(aString);
}

//Case 2: Where we receive parameter as a byte array where conversion is not required and we directly assign it to a
public void setA(byte[] a){
this.a=a;
}

Answer 1

Well, it compiles so literally you can! :-) Anyway it's probably not the answer you want to hear. From the two methods, only setA(byte[]) is setter in the meaning as was coined by JavaBeans specification. The other method is just helper method with name starting with set . I think your code is ok in most cases. Some problem could arise if some reflection-based tool scanned the methods (rather than fields because they are public) and tried to guess the field type from method parameter type - it would be confused then.

Also I would also consider to reimplement helper method as:

public void setA(String aString){
    setA(convertTobyteArray(aString));
}

Answer 2

A setter is simply a public void method that changes the value of an encapsulated field, and in Java you can add as much methods as you want with the same name and different signatures thanks to method overloading .

So the answer is YES you can have multiple setters with different parameters and it's not considered a bad practice.