Think in java 答案_Chapter 4_Exercise 2

阅前声明: http://blog.csdn.net/heimaoxiaozi/archive/2007/01/19/1487884.aspx

/****************** Exercise 2 ******************
* Add an overloaded constructor to Exercise 1
* that takes a String argument and prints it
* along with your message.
***********************************************/
public class E02_OverloadedConstructor {
E02_OverloadedConstructor() {
System.out.println("Default constructor");
}
E02_OverloadedConstructor(String s) {
System.out.println("String arg constructor");
System.out.println(s);
}
public static void main(String args[]) {
// Call default version:
new E02_OverloadedConstructor();
// Call overloaded version:
new E02_OverloadedConstructor("Overloaded");
}
}

//+M java E02_OverloadedConstructor

** A second way to do this is to explicitly call the default constructor inside the overloaded constructor using this:

public class E02_OverloadedConstructor2 {
E02_OverloadedConstructor2() {
System.out.println("Default constructor");
}
E02_OverloadedConstructor2(String s) {
this();
System.out.println(s);
}
public static void main(String args[]) {
// Call default version:
new E02_OverloadedConstructor2();
// Call overloaded version:
new E02_OverloadedConstructor2("Overloaded");
}
}

//+M java E02_OverloadedConstructor2