Remove use of Boolean constructors

Codacy warns us that there are several references to Boolean
constructors in the tests. Direct usage of the Boolean constructor is
discouraged and even deprecated in Java 9 [1]. Boolean constructor use
can easily be replaced with the constant instances.

This commit contains the following changes:

 - replace references to Boolean constructors with boolean constants in
   JSP tag tests
 - update the copyright year where necessary
 - BooleanComparatorTests is intentionally left unchanged as it should
   also work with the non-constant instances correctly

 [1] http://download.java.net/java/jdk9/docs/api/java/lang/Boolean.html#Boolean-boolean-

Issue: SPR-15076

spring-webmvc/src/test/java/org/springframework/web/servlet/tags/form/CheckboxTagTests.java

@@ -164,7 +164,7 @@ public class CheckboxTagTests extends AbstractFormTagTests {
 
 	@Test
 	public void withSingleValueBooleanObjectUnchecked() throws Exception {
-		this.bean.setSomeBoolean(new Boolean(false));
+		this.bean.setSomeBoolean(Boolean.FALSE);
 		this.tag.setPath("someBoolean");
 		int result = this.tag.doStartTag();
 		assertEquals(Tag.SKIP_BODY, result);
@@ -692,7 +692,7 @@ public class CheckboxTagTests extends AbstractFormTagTests {
 		this.bean.setDate(getDate());
 		this.bean.setName("Rob Harrop");
 		this.bean.setJedi(true);
-		this.bean.setSomeBoolean(new Boolean(true));
+		this.bean.setSomeBoolean(Boolean.TRUE);
 		this.bean.setStringArray(new String[] {"bar", "foo"});
 		this.bean.setSomeIntegerArray(new Integer[] {new Integer(2), new Integer(1)});
 		this.bean.setOtherColours(colours);

spring-webmvc/src/test/java/org/springframework/web/servlet/tags/form/CheckboxesTagTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -773,7 +773,7 @@ public class CheckboxesTagTests extends AbstractFormTagTests {
 		this.bean.setDate(getDate());
 		this.bean.setName("Rob Harrop");
 		this.bean.setJedi(true);
-		this.bean.setSomeBoolean(new Boolean(true));
+		this.bean.setSomeBoolean(Boolean.TRUE);
 		this.bean.setStringArray(new String[] {"bar", "foo"});
 		this.bean.setSomeIntegerArray(new Integer[] {new Integer(2), new Integer(1)});
 		this.bean.setOtherColours(colours);

spring-webmvc/src/test/java/org/springframework/web/servlet/tags/form/RadioButtonsTagTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -620,7 +620,7 @@ public class RadioButtonsTagTests extends AbstractFormTagTests {
 		this.bean.setDate(getDate());
 		this.bean.setName("Rob Harrop");
 		this.bean.setJedi(true);
-		this.bean.setSomeBoolean(new Boolean(true));
+		this.bean.setSomeBoolean(Boolean.TRUE);
 		this.bean.setStringArray(new String[] {"bar", "foo"});
 		this.bean.setSomeIntegerArray(new Integer[] {new Integer(2), new Integer(1)});
 		this.bean.setOtherColours(colours);