66 lines
1.6 KiB
Java
66 lines
1.6 KiB
Java
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// functional/FunctionVariants.java
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// <20>2016 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://mindviewinc.com/Books/OnJava/ for more book information.
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import java.util.function.*;
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class Foo {}
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class Bar {
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Foo f;
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public Bar(Foo f) { this.f = f; }
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}
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class IBaz {
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int i;
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public IBaz(int i) {
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this.i = i;
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}
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}
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class LBaz {
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long l;
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public LBaz(long l) {
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this.l = l;
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}
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}
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class DBaz {
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double d;
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public DBaz(double d) {
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this.d = d;
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}
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}
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public class FunctionVariants {
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static Function<Foo,Bar> f1 = f -> new Bar(f);
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static IntFunction<IBaz> f2 = i -> new IBaz(i);
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static LongFunction<LBaz> f3 = l -> new LBaz(l);
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static DoubleFunction<DBaz> f4 = d -> new DBaz(d);
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static ToIntFunction<IBaz> f5 = ib -> ib.i;
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static ToLongFunction<LBaz> f6 = lb -> lb.l;
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static ToDoubleFunction<DBaz> f7 = db -> db.d;
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static IntToLongFunction f8 = i -> i;
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static IntToDoubleFunction f9 = i -> i;
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static LongToIntFunction f10 = l -> (int)l;
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static LongToDoubleFunction f11 = l -> l;
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static DoubleToIntFunction f12 = d -> (int)d;
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static DoubleToLongFunction f13 = d -> (long)d;
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public static void main(String[] args) {
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Bar b = f1.apply(new Foo());
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IBaz ib = f2.apply(11);
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LBaz lb = f3.apply(11);
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DBaz db = f4.apply(11);
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int i = f5.applyAsInt(ib);
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long l = f6.applyAsLong(lb);
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double d = f7.applyAsDouble(db);
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l = f8.applyAsLong(12);
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d = f9.applyAsDouble(12);
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i = f10.applyAsInt(12);
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d = f11.applyAsDouble(12);
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i = f12.applyAsInt(13.0);
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l = f13.applyAsLong(13.0);
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}
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}
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