Add java 8 for examples.

Author: javadev

examples/src/main/java/com/github/underscore/examples/Chaining.java

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright 2015-2018 Valentyn Kolesnikov
+ * Copyright 2015-2020 Valentyn Kolesnikov
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -24,6 +24,7 @@
 package com.github.underscore.examples;
 
 import java.util.*;
+import java.util.function.Function;
 
 /**
  * Examples for underscore-java.
@@ -36,22 +37,17 @@ public static <E> E first(final Iterable<E> iterable) {
     }
 
     public static <T, E> List<T> map(final List<E> list, final Function<? super E, T> func) {
-        final List<T> transformed = new ArrayList<T>(list.size());
+        final List<T> transformed = new ArrayList<>(list.size());
         for (E element : list) {
-            transformed.add(func.apply(element));
+            func.andThen(transformed::add).apply(element);
         }
         return transformed;
     }
 
     public static <E, T extends Comparable<? super T>> List<E> sortBy(final List<E> iterable,
         final Function<E, T> func) {
-        final List<E> sortedList = new ArrayList<E>(iterable);
-        Collections.sort(sortedList, new Comparator<E>() {
-            @Override
-            public int compare(E o1, E o2) {
-                return func.apply(o1).compareTo(func.apply(o2));
-            }
-        });
+        final List<E> sortedList = new ArrayList<>(iterable);
+        sortedList.sort(Comparator.comparing(func::apply));
         return sortedList;
     }
 
@@ -65,7 +61,7 @@ public int compare(E o1, E o2) {
 => "moe is 21"
 */
     public static <T> Chain<T> chain(final List<T> list) {
-        return new Chaining.Chain<T>(list);
+        return new Chaining.Chain<>(list);
     }
 
     public static class Chain<T> {
@@ -82,15 +78,15 @@ public Chain(final List<T> list) {
         }
 
         public Chain<T> first() {
-            return new Chain<T>(Chaining.first(list));
+            return new Chain<>(Chaining.first(list));
         }
 
         public <F> Chain<F> map(final Function<? super T, F> func) {
-            return new Chain<F>(Chaining.map(list, func));
+            return new Chain<>(Chaining.map(list, func));
         }
 
         public <F extends Comparable<? super F>> Chain<T> sortBy(final Function<T, F> func) {
-            return new Chain<T>(Chaining.sortBy(list, func));
+            return new Chain<>(Chaining.sortBy(list, func));
         }
 
         public T item() {

examples/src/main/java/com/github/underscore/examples/FromJson.java

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright 2015-2018 Valentyn Kolesnikov
+ * Copyright 2015-2020 Valentyn Kolesnikov
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -115,7 +115,7 @@ private Object readValue() {
 
         private List<Object> readArray() {
             read();
-            List<Object> array = new ArrayList<Object>();
+            List<Object> array = new ArrayList<>();
             skipWhiteSpace();
             if (readChar(']')) {
                 return array;
@@ -133,7 +133,7 @@ private List<Object> readArray() {
 
         private Map<String, Object> readObject() {
             read();
-            Map<String, Object> object = new LinkedHashMap<String, Object>();
+            Map<String, Object> object = new LinkedHashMap<>();
             skipWhiteSpace();
             if (readChar('}')) {
                 return object;

examples/src/main/java/com/github/underscore/examples/FromXml.java

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright 2015-2018 Valentyn Kolesnikov
+ * Copyright 2015-2020 Valentyn Kolesnikov
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -23,6 +23,7 @@
  */
 package com.github.underscore.examples;
 
+import java.nio.charset.StandardCharsets;
 import java.util.*;
 
 /**
@@ -44,7 +45,7 @@ private static Object getValue(final Object value) {
 
     @SuppressWarnings("unchecked")
     private static Map<String, Object> createMap(final org.w3c.dom.Node node) {
-        final Map<String, Object> map = new LinkedHashMap<String, Object>();
+        final Map<String, Object> map = new LinkedHashMap<>();
         final org.w3c.dom.NodeList nodeList = node.getChildNodes();
         for (int index = 0; index < nodeList.getLength(); index++) {
             final org.w3c.dom.Node currentNode = nodeList.item(index);
@@ -63,7 +64,7 @@ private static Map<String, Object> createMap(final org.w3c.dom.Node node) {
                 if (object instanceof List) {
                     ((List<Object>) object).add(getValue(value));
                 } else {
-                    final List<Object> objects = new ArrayList<Object>();
+                    final List<Object> objects = new ArrayList<>();
                     objects.add(object);
                     objects.add(getValue(value));
                     map.put(name, objects);
@@ -77,7 +78,7 @@ private static Map<String, Object> createMap(final org.w3c.dom.Node node) {
 
     public static Object fromXml(final String xml) {
         try {
-            final java.io.InputStream stream = new java.io.ByteArrayInputStream(xml.getBytes("UTF-8"));
+            final java.io.InputStream stream = new java.io.ByteArrayInputStream(xml.getBytes(StandardCharsets.UTF_8));
             final javax.xml.parsers.DocumentBuilderFactory factory =
                 javax.xml.parsers.DocumentBuilderFactory.newInstance();
             factory.setNamespaceAware(true);

examples/src/main/java/com/github/underscore/examples/Function.java

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright 2015-2018 Valentyn Kolesnikov
+ * Copyright 2015-2020 Valentyn Kolesnikov
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal

examples/src/main/java/com/github/underscore/examples/Function3.java

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright 2015-2018 Valentyn Kolesnikov
+ * Copyright 2015-2020 Valentyn Kolesnikov
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -24,6 +24,7 @@
 package com.github.underscore.examples;
 
 import java.util.*;
+import java.util.function.Predicate;
 
 /**
  * Examples for underscore-java.
@@ -45,16 +46,11 @@ public static <E> boolean some(final Iterable<E> iterable, final Predicate<E> pr
     }
 
     public static <E> boolean contains(final Iterable<E> iterable, final E elem) {
-        return some(iterable, new Predicate<E>() {
-            @Override
-            public boolean test(E e) {
-                return elem == null ? e == null : elem.equals(e);
-            }
-        });
+        return some(iterable, e -> Objects.equals(elem, e));
     }
 
     public static <E> List<E> filter(final List<E> list, final Predicate<E> pred) {
-        final List<E> filtered = new ArrayList<E>();
+        final List<E> filtered = new ArrayList<>();
         for (E element : list) {
             if (pred.test(element)) {
                 filtered.add(element);
@@ -64,12 +60,7 @@ public static <E> List<E> filter(final List<E> list, final Predicate<E> pred) {
     }
 
     public static <E> List<E> intersection(final List<E> list1, final List<E> list2) {
-        return filter(list1, new Predicate<E>() {
-            @Override
-            public boolean test(E elem) {
-                return contains(list2, elem);
-            }
-        });
+        return filter(list1, elem -> contains(list2, elem));
     }
 
 /*
@@ -78,10 +69,10 @@ public boolean test(E elem) {
 */
     @SuppressWarnings("unchecked")
     public static <E> List<E> intersection(final List<E> list, final List<E> ... lists) {
-        final Stack<List<E>> stack = new Stack<List<E>>();
+        final Stack<List<E>> stack = new Stack<>();
         stack.push(list);
-        for (int index = 0; index < lists.length; index += 1) {
-          stack.push(intersection(stack.peek(), lists[index]));
+        for (List<E> es : lists) {
+            stack.push(intersection(stack.peek(), es));
         }
         return stack.peek();
     }

examples/src/main/java/com/github/underscore/examples/Intersection.java

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright 2015-2018 Valentyn Kolesnikov
+ * Copyright 2015-2020 Valentyn Kolesnikov
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -23,6 +23,8 @@
  */
 package com.github.underscore.examples;
 
+import java.util.Objects;
+
 public final class Optional<T> {
     private static final Optional<?> EMPTY = new Optional();
     private final T arg;
@@ -39,12 +41,12 @@ private Optional(final T arg) {
     }
 
     public static <T> Optional<T> of(final T arg) {
-        return new Optional<T>(arg);
+        return new Optional<>(arg);
     }
 
     public static <T> Optional<T> fromNullable(final T nullableReference) {
         return nullableReference == null ? Optional.<T>absent()
-            : new Optional<T>(nullableReference);
+            : new Optional<>(nullableReference);
     }
 
     @SuppressWarnings("unchecked")
@@ -91,7 +93,7 @@ public boolean equals(final Object o) {
         if (absent != optional.absent) {
             return false;
         }
-        return !(arg == null ? optional.arg != null : !arg.equals(optional.arg));
+        return Objects.equals(arg, optional.arg);
     }
 
     @Override

examples/src/main/java/com/github/underscore/examples/Optional.java

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright 2015-2018 Valentyn Kolesnikov
+ * Copyright 2015-2020 Valentyn Kolesnikov
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -24,6 +24,7 @@
 package com.github.underscore.examples;
 
 import java.util.*;
+import java.util.function.Function;
 
 /**
  * Examples for underscore-java.
@@ -33,7 +34,7 @@
 public class SnakeCase {
     private static final java.util.regex.Pattern RE_LATIN_1 = java.util.regex.Pattern.compile(
         "[\\xc0-\\xd6\\xd8-\\xde\\xdf-\\xf6\\xf8-\\xff]");
-    private static final Map<String, String> DEBURRED_LETTERS = new LinkedHashMap<String, String>();
+    private static final Map<String, String> DEBURRED_LETTERS = new LinkedHashMap<>();
 
     static {
         String[] deburredLetters = new String[] {
@@ -87,7 +88,7 @@ public static String deburr(final String string) {
 
     public static List<String> words(final String string) {
         final String localString = baseToString(string);
-        final List<String> result = new ArrayList<String>();
+        final List<String> result = new ArrayList<>();
         final java.util.regex.Matcher matcher = reWords.matcher(localString);
         while (matcher.find()) {
             result.add(matcher.group());
@@ -97,18 +98,16 @@ public static List<String> words(final String string) {
 
     private static Function<String, String> createCompounder(
         final Function3<String, String, Integer, String> callback) {
-        return new Function<String, String>() {
-            public String apply(final String string) {
-                int index = -1;
-                List<String> array = words(deburr(string));
-                int length = array.size();
-                String result = "";
+        return string -> {
+            int index = -1;
+            List<String> array = words(deburr(string));
+            int length = array.size();
+            String result = "";
 
-                while (++index < length) {
-                    result = callback.apply(result, array.get(index), index);
-                }
-                return result;
+            while (++index < length) {
+                result = callback.apply(result, array.get(index), index);
             }
+            return result;
         };
     }
 
@@ -123,10 +122,7 @@ public String apply(final String string) {
 => 'foo_bar'
 */
     public static String snakeCase(final String string) {
-        return createCompounder(new Function3<String, String, Integer, String>() {
-            public String apply(final String result, final String word, final Integer index) {
-                return result + (index > 0 ? "_" : "") + word.toLowerCase(Locale.getDefault());
-            }
-        }).apply(string);
+        return createCompounder((result, word, index) -> result + (index > 0 ? "_" : "")
+                + word.toLowerCase(Locale.getDefault())).apply(string);
     }
 }