forked from BruceEckel/OnJava8-Examples
/
MethodReferences.java
53 lines (47 loc) · 1.14 KB
/
MethodReferences.java
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// functional/MethodReferences.java
// (c)2017 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
import java.util.*;
interface Callable { // [1]
void call(String s);
}
class Describe {
void show(String msg) { // [2]
System.out.println(msg);
}
}
public class MethodReferences {
static void hello(String name) { // [3]
System.out.println("Hello, " + name);
}
static class Description {
String about;
Description(String desc) { about = desc; }
void help(String msg) { // [4]
System.out.println(about + " " + msg);
}
}
static class Helper {
static void assist(String msg) { // [5]
System.out.println(msg);
}
}
public static void main(String[] args) {
Describe d = new Describe();
Callable c = d::show; // [6]
c.call("call()"); // [7]
c = MethodReferences::hello; // [8]
c.call("Bob");
c = new Description("valuable")::help; // [9]
c.call("information");
c = Helper::assist; // [10]
c.call("Help!");
}
}
/* Output:
call()
Hello, Bob
valuable information
Help!
*/