Polish contribution

See gh-23300

spring-core/src/main/java/org/springframework/core/style/DefaultValueStyler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -40,12 +40,13 @@ import org.springframework.util.ObjectUtils;
  */
 public class DefaultValueStyler implements ValueStyler {
 
-	private static final String EMPTY = "[empty]";
+	private static final String EMPTY = "[[empty]]";
 	private static final String NULL = "[null]";
 	private static final String COLLECTION = "collection";
 	private static final String SET = "set";
 	private static final String LIST = "list";
 	private static final String MAP = "map";
+	private static final String EMPTY_MAP = MAP + EMPTY;
 	private static final String ARRAY = "array";
 
 
@@ -83,7 +84,7 @@ public class DefaultValueStyler implements ValueStyler {
 
 	private <K, V> String style(Map<K, V> value) {
 		if (value.isEmpty()) {
-			return MAP + '[' + EMPTY + ']';
+			return EMPTY_MAP;
 		}
 
 		StringJoiner result = new StringJoiner(", ", "[", "]");
@@ -101,7 +102,7 @@ public class DefaultValueStyler implements ValueStyler {
 		String collectionType = getCollectionTypeString(value);
 
 		if (value.isEmpty()) {
-			return collectionType + '[' + EMPTY + ']';
+			return collectionType + EMPTY;
 		}
 
 		StringJoiner result = new StringJoiner(", ", "[", "]");
@@ -125,7 +126,7 @@ public class DefaultValueStyler implements ValueStyler {
 
 	private String styleArray(Object[] array) {
 		if (array.length == 0) {
-			return ARRAY + '<' + ClassUtils.getShortName(array.getClass().getComponentType()) + '>' + '[' + EMPTY + ']';
+			return ARRAY + '<' + ClassUtils.getShortName(array.getClass().getComponentType()) + '>' + EMPTY;
 		}
 
 		StringJoiner result = new StringJoiner(", ", "[", "]");

spring-core/src/main/java/org/springframework/util/ObjectUtils.java

@@ -710,11 +710,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (Object o : array) {
-			sj.add(String.valueOf(o));
+			stringJoiner.add(String.valueOf(o));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -734,11 +734,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (boolean b : array) {
-			sj.add(String.valueOf(b));
+			stringJoiner.add(String.valueOf(b));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -758,11 +758,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (byte b : array) {
-			sj.add(String.valueOf(b));
+			stringJoiner.add(String.valueOf(b));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -782,11 +782,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (char c : array) {
-			sj.add('\'' + String.valueOf(c) + '\'');
+			stringJoiner.add('\'' + String.valueOf(c) + '\'');
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -806,11 +806,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (double d : array) {
-			sj.add(String.valueOf(d));
+			stringJoiner.add(String.valueOf(d));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -830,11 +830,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (float f : array) {
-			sj.add(String.valueOf(f));
+			stringJoiner.add(String.valueOf(f));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -854,11 +854,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (int i : array) {
-			sj.add(String.valueOf(i));
+			stringJoiner.add(String.valueOf(i));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -878,11 +878,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (long l : array) {
-			sj.add(String.valueOf(l));
+			stringJoiner.add(String.valueOf(l));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 	/**
@@ -902,11 +902,11 @@ public abstract class ObjectUtils {
 		if (length == 0) {
 			return EMPTY_ARRAY;
 		}
-		StringJoiner sj = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
+		StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
 		for (short s : array) {
-			sj.add(String.valueOf(s));
+			stringJoiner.add(String.valueOf(s));
 		}
-		return sj.toString();
+		return stringJoiner.toString();
 	}
 
 }

spring-core/src/test/java/org/springframework/core/style/DefaultValueStylerTests.java

@@ -1,6 +1,20 @@
-package org.springframework.core.style;
+/*
+ * Copyright 2002-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-import org.junit.Test;
+package org.springframework.core.style;
 
 import java.util.Arrays;
 import java.util.Collections;
@@ -10,32 +24,37 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
+import org.junit.Test;
+
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class DefaultValueStylerTest {
+/**
+ * Unit tests for {@link DefaultValueStyler}.
+ *
+ * @since 5.2
+ */
+public class DefaultValueStylerTests {
+
+	private final DefaultValueStyler styler = new DefaultValueStyler();
 
-	private DefaultValueStyler styler = new DefaultValueStyler();
 
 	@Test
-	public void style() throws NoSuchMethodException {
+	public void styleBasics() throws NoSuchMethodException {
 		assertThat(styler.style(null)).isEqualTo("[null]");
-
 		assertThat(styler.style("str")).isEqualTo("'str'");
-
 		assertThat(styler.style(String.class)).isEqualTo("String");
-
 		assertThat(styler.style(String.class.getMethod("toString"))).isEqualTo("toString@String");
 	}
 
 	@Test
-	public void style_plainObject() {
-		final Object obj = new Object();
+	public void stylePlainObject() {
+		Object obj = new Object();
 
 		assertThat(styler.style(obj)).isEqualTo(String.valueOf(obj));
 	}
 
 	@Test
-	public void style_map() {
+	public void styleMaps() {
 		Map<String, Integer> map = Collections.emptyMap();
 		assertThat(styler.style(map)).isEqualTo("map[[empty]]");
 
@@ -49,19 +68,19 @@ public class DefaultValueStylerTest {
 	}
 
 	@Test
-	public void style_entry() {
-		final Map<String, Integer> map = new LinkedHashMap<>();
+	public void styleMapEntries() {
+		Map<String, Integer> map = new LinkedHashMap<>();
 		map.put("key1", 1);
 		map.put("key2", 2);
 
-		final Iterator<Map.Entry<String, Integer>> entries = map.entrySet().iterator();
+		Iterator<Map.Entry<String, Integer>> entries = map.entrySet().iterator();
 
 		assertThat(styler.style(entries.next())).isEqualTo("'key1' -> 1");
 		assertThat(styler.style(entries.next())).isEqualTo("'key2' -> 2");
 	}
 
 	@Test
-	public void style_collection() {
+	public void styleCollections() {
 		List<Integer> list = Collections.emptyList();
 		assertThat(styler.style(list)).isEqualTo("list[[empty]]");
 
@@ -73,27 +92,27 @@ public class DefaultValueStylerTest {
 	}
 
 	@Test
-	public void style_primitiveArray() {
+	public void stylePrimitiveArrays() {
 		int[] array = new int[0];
 		assertThat(styler.style(array)).isEqualTo("array<Object>[[empty]]");
 
-		array = new int[]{1};
+		array = new int[] { 1 };
 		assertThat(styler.style(array)).isEqualTo("array<Integer>[1]");
 
-		array = new int[]{1, 2};
+		array = new int[] { 1, 2 };
 		assertThat(styler.style(array)).isEqualTo("array<Integer>[1, 2]");
 	}
 
 	@Test
-	public void style_objectArray() {
+	public void styleObjectArrays() {
 		String[] array = new String[0];
 		assertThat(styler.style(array)).isEqualTo("array<String>[[empty]]");
 
-		array = new String[]{"str1"};
+		array = new String[] { "str1" };
 		assertThat(styler.style(array)).isEqualTo("array<String>['str1']");
 
-		array = new String[]{"str1", "str2"};
+		array = new String[] { "str1", "str2" };
 		assertThat(styler.style(array)).isEqualTo("array<String>['str1', 'str2']");
 	}
 
-}
+}