package io.github.dunwu.javacore.jdk8.stream; import java.util.Arrays; import java.util.List; import java.util.function.Supplier; import java.util.stream.Stream; /** * Testing the order of execution. * * @author Benjamin Winterberg */ public class Streams5 { public static void main(String[] args) { List<String> strings = Arrays.asList("d2", "a2", "b1", "b3", "c"); // test1(strings); // test2(strings); // test3(strings); // test4(strings); // test5(strings); // test6(strings); // test7(strings); test8(strings); } private static void test8(List<String> stringCollection) { Supplier<Stream<String>> streamSupplier = () -> stringCollection.stream().filter(s -> s.startsWith("a")); streamSupplier.get().anyMatch(s -> true); streamSupplier.get().noneMatch(s -> true); } // stream has already been operated upon or closed private static void test7(List<String> stringCollection) { Stream<String> stream = stringCollection.stream().filter(s -> s.startsWith("a")); stream.anyMatch(s -> true); stream.noneMatch(s -> true); } // short-circuit private static void test6(List<String> stringCollection) { stringCollection.stream().map(s -> { System.out.println("map: " + s); return s.toUpperCase(); }).anyMatch(s -> { System.out.println("anyMatch: " + s); return s.startsWith("A"); }); } private static void test5(List<String> stringCollection) { stringCollection.stream().filter(s -> { System.out.println("filter: " + s); return s.toLowerCase().startsWith("a"); }).sorted((s1, s2) -> { System.out.printf("sort: %s; %s\n", s1, s2); return s1.compareTo(s2); }).map(s -> { System.out.println("map: " + s); return s.toUpperCase(); }).forEach(s -> System.out.println("forEach: " + s)); } // sorted = horizontal private static void test4(List<String> stringCollection) { stringCollection.stream().sorted((s1, s2) -> { System.out.printf("sort: %s; %s\n", s1, s2); return s1.compareTo(s2); }).filter(s -> { System.out.println("filter: " + s); return s.toLowerCase().startsWith("a"); }).map(s -> { System.out.println("map: " + s); return s.toUpperCase(); }).forEach(s -> System.out.println("forEach: " + s)); } private static void test3(List<String> stringCollection) { stringCollection.stream().filter(s -> { System.out.println("filter: " + s); return s.startsWith("a"); }).map(s -> { System.out.println("map: " + s); return s.toUpperCase(); }).forEach(s -> System.out.println("forEach: " + s)); } private static void test2(List<String> stringCollection) { stringCollection.stream().map(s -> { System.out.println("map: " + s); return s.toUpperCase(); }).filter(s -> { System.out.println("filter: " + s); return s.startsWith("A"); }).forEach(s -> System.out.println("forEach: " + s)); } private static void test1(List<String> stringCollection) { stringCollection.stream().filter(s -> { System.out.println("filter: " + s); return true; }).forEach(s -> System.out.println("forEach: " + s)); } }