Changing method parameter adds parameter to the lambda expression but is adds always also the type, even when shorter lambda declaration is used.

Example:

1) have a code:
public class ClassA {

    interface Iface {
	public String getName(String a);
    }

    public static void main(String[] args) {
	Iface i1 = (String a)-> {return "";};
	Iface i2 = a-> {return "";};
	Iface i3 = (String a)-> "";
	Iface i4 = (a)-> "";

    }
}
2) add parameter to getName


-> 
public class ClassA {

    interface Iface {
	public String getName(String a, Object par1);
    }

    public static void main(String[] args) {
	Iface i1 = (String a, Object par1)-> {return "";};
	Iface i2 = a, Object par1-> {return "";};  //<=== error
	Iface i3 = (String a, Object par1)-> "";
	Iface i4 = (a, Object par1)-> ""; //<=== error

    }
}


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