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BAEL-9040 Two quick improvements to the foreach article

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-Added more tests for forEach tutorial
This commit is contained in:
Dhawal Kapil 2018-10-21 00:26:30 +05:30
parent 5597bf69cd
commit b2f3115cfd
1 changed files with 54 additions and 9 deletions
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63
core-java-8/src/test/java/com/baeldung/java8/Java8ForEachUnitTest.java
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@ -4,8 +4,15 @@ import org.junit.Test;
import org.slf4j.Logger; import org.slf4j.Logger;
import org.slf4j.LoggerFactory; import org.slf4j.LoggerFactory;
import java.util.ArrayDeque;
import java.util.ArrayList; import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List; import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import java.util.function.Consumer; import java.util.function.Consumer;
public class Java8ForEachUnitTest { public class Java8ForEachUnitTest {
@ -29,8 +36,18 @@ public class Java8ForEachUnitTest {
} }
// Java 8 - forEach // Java 8 - forEach
LOG.debug("--- forEach method ---"); names.forEach(name -> {
names.forEach(name -> LOG.debug(name)); System.out.println(name);
});
LOG.debug("--- Print Consumer ---");
Consumer<String> printConsumer = new Consumer<String>() {
public void accept(String name) {
System.out.println(name);
};
};
names.forEach(printConsumer);
// Anonymous inner class that implements Consumer interface // Anonymous inner class that implements Consumer interface
LOG.debug("--- Anonymous inner class ---"); LOG.debug("--- Anonymous inner class ---");
@ -40,17 +57,45 @@ public class Java8ForEachUnitTest {
} }
}); });
// Create a Consumer implementation to then use in a forEach method // Java 8 - forEach - Lambda Syntax
Consumer<String> consumerNames = name -> { LOG.debug("--- forEach method ---");
LOG.debug(name); names.forEach(name -> LOG.debug(name));
};
LOG.debug("--- Implementation of Consumer interface ---");
names.forEach(consumerNames);
// Print elements using a Method Reference // Java 8 - forEach - Print elements using a Method Reference
LOG.debug("--- Method Reference ---"); LOG.debug("--- Method Reference ---");
names.forEach(LOG::debug); names.forEach(LOG::debug);
}
@Test
public void givenList_thenIterateAndPrintResults() {
List<String> names = Arrays.asList("Larry", "Steve", "James");
names.forEach(System.out::println);
}
@Test
public void givenSet_thenIterateAndPrintResults() {
Set<String> uniqueNames = new HashSet<>(Arrays.asList("Larry", "Steve", "James"));
uniqueNames.forEach(System.out::println);
}
@Test
public void givenQueue_thenIterateAndPrintResults() {
Queue<String> namesQueue = new ArrayDeque<>(Arrays.asList("Larry", "Steve", "James"));
namesQueue.forEach(System.out::println);
}
@Test
public void givenMap_thenIterateAndPrintResults() {
Map<Integer, String> namesMap = new HashMap<>();
namesMap.put(1, "Larry");
namesMap.put(2, "Steve");
namesMap.put(3, "James");
namesMap.entrySet()
.forEach(entry -> System.out.println(entry.getKey() + " " + entry.getValue()));
} }
} }