37 lines
800 B
Java
37 lines
800 B
Java
// functional/CtorReference.java
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// (c)2020 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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class Dog {
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String name;
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int age = -1; // For "unknown"
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Dog() { name = "stray"; }
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Dog(String nm) { name = nm; }
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Dog(String nm, int yrs) { name = nm; age = yrs; }
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}
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interface MakeNoArgs {
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Dog make();
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}
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interface Make1Arg {
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Dog make(String nm);
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}
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interface Make2Args {
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Dog make(String nm, int age);
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}
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public class CtorReference {
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public static void main(String[] args) {
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MakeNoArgs mna = Dog::new; // [1]
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Make1Arg m1a = Dog::new; // [2]
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Make2Args m2a = Dog::new; // [3]
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Dog dn = mna.make();
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Dog d1 = m1a.make("Comet");
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Dog d2 = m2a.make("Ralph", 4);
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}
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}
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