Correct getter and setter for a JavaBean

Question

I have a class which is used as a DTO I am wondering what the correct naming for the getter and setter methods is.

Current code:

public class NiceClass {
    private String PE_DATAB;

    public void setPE_DATAB(final String PE_DATAB) {
        this.PE_DATAB = PE_DATAB;
    }
}

But after reading the JavaBeansSpec my best guess is:

public void setPe_DATAB(final String PE_DATAB) {
    this.PE_DATAB = PE_DATAB;
}

What is the correct naming for the setter method above for the variable PE_DATAB?

I can not rename the variable!

Answer 1

public class NiceClass {
    private String PE_DATAB;

    public void setPE_DATAB(final String PE_DATAB) {
        this.PE_DATAB = PE_DATAB;
    }
}

is the correct code according to the JavaBeans specification.

You can check that it is correct with the following code:

public class Main {

    public static void main(String[] args) throws Exception {
        BeanInfo info = Introspector.getBeanInfo(NiceClass.class);
        System.out.println("Setter: " + info.getPropertyDescriptors()[0].getWriteMethod());
        // prints "Setter: public void Main$NiceClass.setPE_DATAB(java.lang.String)"
        System.out.println("Name of variable: " + info.getPropertyDescriptors()[0].getName());
        // prints "Name of variable: PE_DATAB"
    }

    public class NiceClass {

        private String PE_DATAB;

        public void setPE_DATAB(String PE_DATAB) {
            this.PE_DATAB = PE_DATAB;
        }

    }

}

This is defined in section 8.3.1 of the JavaBean specification. Quoting:

By default, we use design patterns to locate properties by looking for methods of the form:

public <PropertyType> get<PropertyName>();

public void set<PropertyName>(<PropertyType> a);

If we discover a matching pair of get<PropertyName> and set<PropertyName> methods that take and return the same type, then we regard these methods as defining a read-write property whose name will be <propertyName>.