Default value for null fields using GSON

问题

I would like to set default values for some fields on my model, so if during deserialization my json has missing fields, those default values are used. What I would like to understand which is the best practice to do this, and why. I should add the control of null in the setters of my model, I should use the try catch to find any cases, I should extend and modify typeAdapter (this solution seems very verbose to me, let me know if I'm wrong) or there is a even better solution?

回答1:

If those won't be available be in JSON data at all, then just initiate the variables.

private int id = -1;
private String name = "User not available";

If there is a probability that you might get null values, then check for it in getters

private String DEFAULT_NAME = "User not available";

private String name;

public String getName(){
  if(null == name) return DEFAULT_NAME;
  return name; 
}

来源：https://stackoverflow.com/questions/52314615/default-value-for-null-fields-using-gson