@JsonProperty seems to only work for non boolean members

Question

I have an object I'm trying to map to JSON and everything seems to work marvelously, except for boolean members, as we can see below:

public class Foo implements Serializable {

    @JsonProperty("this_does_not_work")
    private boolean isBar;

    @JsonProperty("this_works")
    private int bar;

    @JsonProperty("this_works_too")
    public boolean isBar() {
        return isBar;
    }

}

This would be serialized to this:

{
    this_works: ...,
    this_works_too: ...    
}

Why do boolean members can't have a @JsonProperty (but their getters do)?

Answer 1

Summarising the statements from comments: if you change your boolean field name to enabled

@JsonProperty("custom_name")
private boolean enabled;

public boolean isEnabled() {
    return enabled;
}

public void setEnabled(boolean isEnabled) {
    this.enabled = isEnabled;
}

it will give desired output { "custom_name" : true }

The original problem is not following java field naming conventions:

@JsonProperty("custom_name")
@Column(name = "fl_enabled")
private boolean isEnabled;

public boolean isEnabled() {
    return isEnabled;
}

public void setEnabled(boolean isEnabled) {
    this.isEnabled = isEnabled;
}

When FasterXML serializes an object, it looks for fields and getters.

In your case, it found boolean field isEnabled and serialized it with custom_name.

Then it excluded getter of this boolean field from processing - possible getter names to exclude are getIsEnabled and 'isIsEnabled' - you don't have any.

Then it finds method isEnabled that looks like a getter for field enabled. So it takes its value and serializes it with key enabled.

So again, the problem is you should not name boolean fields with prefix is.