Merge pull request alexandregama#35 from craft-coder/java8-stream-sorted

Java 8 - Creates two examples of how to use Streams Sorting its list by using Java 8 closed alexandregama#13

Author: alexandregama

java8-stream-sorted/.gitignore

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+/target/
+build/
+.classpath
+.project
+.settings

java8-stream-sorted/README.md

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+# java8-guides-tutorials
+Java 8 - Guides and Tutorias

java8-stream-sorted/pom.xml

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+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+
+	<groupId>com.craftcoder.java8</groupId>
+	<artifactId>java8-stream-sorted</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<packaging>jar</packaging>
+
+	<name>java8-stream-sorted</name>
+	<url>http://maven.apache.org</url>
+
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+	</properties>
+
+	<dependencies>
+		<!-- TESTING DEPENDENCIES -->
+		<dependency>
+			<groupId>org.hamcrest</groupId>
+			<artifactId>hamcrest-all</artifactId>
+			<version>1.3</version>
+		</dependency>
+
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<version>4.12</version>
+			<scope>test</scope>
+		</dependency>
+        <!-- TESTING DEPENDENCIES -->
+
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-eclipse-plugin</artifactId>
+				<configuration>
+					<downloadSources>true</downloadSources>
+					<downloadJavadocs>true</downloadJavadocs>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

java8-stream-sorted/src/java/test/com/craftcoder/java8/defaultmethod/DefaultMethodTest.java

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+package com.craftcoder.java8.defaultmethod;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class DefaultMethodTest {
+
+	/**
+	 * In this example, we don't need to use the default method send() from PaymentService interface 
+	 */
+	@Ignore
+	@Test
+	public void shouldRetrieveTheDefaultFees() throws Exception {
+		PaymentService service = new PayPalPaymentService();
+		
+		double fees = service.retrieveDefaultFees();
+		
+		assertThat(fees, equalTo(10.9));
+	}
+	
+	@Test
+	public void shouldInvokeTheDefaultMethodFromPaymentService() throws Exception {
+		PaymentService paymentService = new PayPalPaymentService();
+		
+		double valueSent = paymentService.send(20);
+		
+		assertThat(valueSent, equalTo(20.0));
+	}
+	
+}
+
+
+interface PaymentService {
+	
+	double retrieveDefaultFees();
+	
+	default double send(double value) {
+		System.out.println("Sending the value: " + value);
+		
+		return value;
+	}
+	
+}
+
+class PayPalPaymentService implements PaymentService {
+
+	@Override
+	public double retrieveDefaultFees() {
+		return 10.9;
+	}
+	
+}

java8-stream-sorted/src/test/java/com/craftcoder/java8/stream/sorted/StreamWithSortedTest.java

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+package com.craftcoder.java8.stream.sorted;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
+
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.junit.Test;
+
+public class StreamWithSortedTest {
+
+	@Test
+	public void shouldSortTheList() throws Exception {
+		List<String> listOfWords = Arrays.asList("B", "A", "D", "E", "C");
+		
+		List<String> sortedList = listOfWords
+			.stream()
+			.sorted()
+			.collect(Collectors.toList());
+		
+		assertThat(sortedList, contains("A", "B", "C", "D", "E"));
+	}
+	
+	@Test
+	public void shouldSortTheListWithInvertedComparator() throws Exception {
+		List<String> listOfWords = Arrays.asList("B", "A", "D", "E", "C");
+		
+		Comparator<String> inverted = (String o1, String o2) -> o2.compareTo(o1);
+		
+		List<String> sortedList = listOfWords
+				.stream()
+				.sorted(inverted)
+				.collect(Collectors.toList());
+		
+		assertThat(sortedList, contains("E", "D", "C", "B", "A"));
+	}
+	
+}