Improve Java (#1474)

A bunch of small improvements for the Java language.

1. Class highlighting based on [naming conventions](http://www.oracle.com/technetwork/java/javase/overview/codeconventions-135099.html). Because of these conventions, we know that every name which starts with an uppercase letter and contains some lower case letters afterward is a class, interface or enum.
2. Nested generics are now supported. The contents of a generic statement are no longer highlighted as a `function`, but as a `class-name` which is more fitting.
3. Packages will now be highlighted as `namespace`.
4. E.g. `foo::bar`, `bar` will be highlighted as a function.
5. ~Support for `var`.~ #1549
6. `null` is now a keyword. As it should be.

components/prism-java.js

@@ -1,27 +1,54 @@
-Prism.languages.java = Prism.languages.extend('clike', {
-	'keyword': /\b(?:var|abstract|continue|for|new|switch|assert|default|goto|package|synchronized|boolean|do|if|private|this|break|double|implements|protected|throw|byte|else|import|public|throws|case|enum|instanceof|return|transient|catch|extends|int|short|try|char|final|interface|static|void|class|finally|long|strictfp|volatile|const|float|native|super|while)\b/,
-	'number': /\b0b[01]+\b|\b0x[\da-f]*\.?[\da-fp-]+\b|(?:\b\d+\.?\d*|\B\.\d+)(?:e[+-]?\d+)?[df]?/i,
-	'operator': {
-		pattern: /(^|[^.])(?:<<=?|>>>?=?|->|([-+&|])\2|[?:~]|[-+*/%&|^!=<>]=?)/m,
-		lookbehind: true
-	}
-});
+(function (Prism) {
 
-Prism.languages.insertBefore('java','function', {
-	'annotation': {
-		alias: 'punctuation',
-		pattern: /(^|[^.])@\w+/,
-		lookbehind: true
-	}
-});
+	var keywords = /\b(?:abstract|continue|for|new|switch|assert|default|goto|package|synchronized|boolean|do|if|private|this|break|double|implements|protected|throw|byte|else|import|public|throws|case|enum|instanceof|return|transient|catch|extends|int|short|try|char|final|interface|static|void|class|finally|long|strictfp|volatile|const|float|native|super|while|var|null)\b/;
 
-Prism.languages.insertBefore('java', 'class-name', {
-	'generics': {
-		pattern: /<\s*\w+(?:\.\w+)?(?:\s*,\s*\w+(?:\.\w+)?)*>/i,
-		alias: 'function',
-		inside: {
-			keyword: Prism.languages.java.keyword,
-			punctuation: /[<>(),.:]/
+	// based on the java naming conventions
+	var className = /\b[A-Z](?:\w*[a-z]\w*)?\b/;
+
+	Prism.languages.java = Prism.languages.extend('clike', {
+		'class-name': [
+			className,
+
+			// variables and parameters
+			// this to support class names (or generic parameters) which do not contain a lower case letter (also works for methods)
+			/\b[A-Z]\w*(?=\s+\w+\s*[;,=())])/
+		],
+		'keyword': keywords,
+		'function': [
+			Prism.languages.clike.function,
+			{
+				pattern: /(\:\:)[a-z_]\w*/,
+				lookbehind: true
+			}
+		],
+		'number': /\b0b[01][01_]*L?\b|\b0x[\da-f_]*\.?[\da-f_p+-]+\b|(?:\b\d[\d_]*\.?[\d_]*|\B\.\d[\d_]*)(?:e[+-]?\d[\d_]*)?[dfl]?/i,
+		'operator': {
+			pattern: /(^|[^.])(?:<<=?|>>>?=?|->|([-+&|])\2|[?:~]|[-+*/%&|^!=<>]=?)/m,
+			lookbehind: true
+		}
+	});
+
+	Prism.languages.insertBefore('java', 'class-name', {
+		'annotation': {
+			alias: 'punctuation',
+			pattern: /(^|[^.])@\w+/,
+			lookbehind: true
+		},
+		'namespace': {
+			pattern: /\b(package\s+|import\s+(?:static\s+)?)[a-z]\w*(\.[a-z]\w*)+/,
+			lookbehind: true,
+			inside: {
+				'punctuation': /\./,
+			}
+		},
+		'generics': {
+			pattern: /<(?:[\w\s,.&?]|<(?:[\w\s,.&?]|<(?:[\w\s,.&?]|<[\w\s,.&?]*>)*>)*>)*>/,
+			inside: {
+				'class-name': className,
+				'keyword': keywords,
+				'punctuation': /[<>(),.:]/,
+				'operator': /[?&|]/
+			}
 		}
-	}
-});
+	});
+}(Prism));

tests/languages/java/function_featrue.test

@@ -0,0 +1,32 @@
+void foo(int a) {}
+foo(0);
+Bar::foo;
+
+----------------------------------------------------
+
+[
+	["keyword", "void"],
+	["function", "foo"],
+	["punctuation", "("],
+	["keyword", "int"],
+	" a",
+	["punctuation", ")"],
+	["punctuation", "{"],
+	["punctuation", "}"],
+
+	["function", "foo"],
+	["punctuation", "("],
+	["number", "0"],
+	["punctuation", ")"],
+	["punctuation", ";"],
+
+	["class-name", "Bar"],
+	["operator", ":"],
+	["operator", ":"],
+	["function", "foo"],
+	["punctuation", ";"]
+]
+
+----------------------------------------------------
+
+Checks for functions.

tests/languages/java/generics_feature.test

@@ -7,49 +7,51 @@ Duo<Double, Character> dual = new Duo<Double, Character>(12.2585, 'C');
 [
 	["keyword", "public"],
 	["keyword", "class"],
-	["class-name", ["Solo"]],
+	["class-name", "Solo"],
 	["generics", [
 		["punctuation", "<"],
-		"T",
+		["class-name", "T"],
 		["punctuation", ">"]
 	]],
 	["punctuation", "{"],
 	["punctuation", "}"],
-	"\r\nSolo",
+
+	["class-name", "Solo"],
 	["generics", [
 		["punctuation", "<"],
-		"Integer",
+		["class-name", "Integer"],
 		["punctuation", ">"]
 	]],
 	" val ",
 	["operator", "="],
 	["keyword", "new"],
-	["class-name", ["Solo"]],
+	["class-name", "Solo"],
 	["generics", [
 		["punctuation", "<"],
-		"Integer",
+		["class-name", "Integer"],
 		["punctuation", ">"]
 	]],
 	["punctuation", "("],
 	["punctuation", ")"],
 	["punctuation", ";"],
-	"\r\nDuo",
+
+	["class-name", "Duo"],
 	["generics", [
 		["punctuation", "<"],
-		"Double",
+		["class-name", "Double"],
 		["punctuation", ","],
-		" Character",
+		["class-name", "Character"],
 		["punctuation", ">"]
 	]],
 	" dual ",
 	["operator", "="],
 	["keyword", "new"],
-	["class-name", ["Duo"]],
+	["class-name", "Duo"],
 	["generics", [
 		["punctuation", "<"],
-		"Double",
+		["class-name", "Double"],
 		["punctuation", ","],
-		" Character",
+		["class-name", "Character"],
 		["punctuation", ">"]
 	]],
 	["punctuation", "("],
@@ -62,4 +64,4 @@ Duo<Double, Character> dual = new Duo<Double, Character>(12.2585, 'C');
 
 ----------------------------------------------------
 
-Checks for generics.
+Checks for generics.

tests/languages/java/issue1351.test

@@ -5,23 +5,23 @@ public class AllChangesIndexer extends SiteIndexer<Change.Id, ChangeData, Change
 [
 	["keyword", "public"],
 	["keyword", "class"],
-	["class-name", ["AllChangesIndexer"]],
+	["class-name", "AllChangesIndexer"],
 	["keyword", "extends"],
-	["class-name", ["SiteIndexer"]],
+	["class-name", "SiteIndexer"],
 	["generics", [
 		["punctuation", "<"],
-		"Change",
+		["class-name", "Change"],
 		["punctuation", "."],
-		"Id",
+		["class-name", "Id"],
 		["punctuation", ","],
-		" ChangeData",
+		["class-name", "ChangeData"],
 		["punctuation", ","],
-		" ChangeIndex",
+		["class-name", "ChangeIndex"],
 		["punctuation", ">"]
 	]],
 	["punctuation", "{"]
 ]
 
 ----------------------------------------------------
 
-Checks for generics. See #1351
+Checks for generics. See #1351

tests/languages/java/keyword_feature.test

@@ -1,51 +1,53 @@
 abstract continue for
-new ;
+new
 switch assert default
 goto package synchronized
 boolean do if private
 this break double
-implements ;
+implements
 protected throw byte else
 import public throws case
 enum
-instanceof ;
+instanceof
 return transient catch
-extends ;
+extends
 int short try char
 final
-interface ;
+interface
 static void
-class ;
+class
 finally long
 strictfp volatile const
 float native super while
+var null
 
 ----------------------------------------------------
 
 [
 	["keyword", "abstract"], ["keyword", "continue"], ["keyword", "for"],
-	["keyword", "new"], ["punctuation", ";"],
+	["keyword", "new"],
 	["keyword", "switch"], ["keyword", "assert"], ["keyword", "default"],
 	["keyword", "goto"], ["keyword", "package"], ["keyword", "synchronized"],
 	["keyword", "boolean"], ["keyword", "do"], ["keyword", "if"], ["keyword", "private"],
 	["keyword", "this"], ["keyword", "break"], ["keyword", "double"],
-	["keyword", "implements"], ["punctuation", ";"],
+	["keyword", "implements"],
 	["keyword", "protected"], ["keyword", "throw"], ["keyword", "byte"], ["keyword", "else"],
 	["keyword", "import"], ["keyword", "public"], ["keyword", "throws"], ["keyword", "case"],
 	["keyword", "enum"],
-	["keyword", "instanceof"], ["punctuation", ";"],
+	["keyword", "instanceof"],
 	["keyword", "return"], ["keyword", "transient"], ["keyword", "catch"],
-	["keyword", "extends"], ["punctuation", ";"],
+	["keyword", "extends"],
 	["keyword", "int"], ["keyword", "short"], ["keyword", "try"], ["keyword", "char"],
 	["keyword", "final"],
-	["keyword", "interface"], ["punctuation", ";"],
-	["keyword", "static"],	["keyword", "void"],
-	["keyword", "class"], ["punctuation", ";"],
+	["keyword", "interface"],
+	["keyword", "static"], ["keyword", "void"],
+	["keyword", "class"],
 	["keyword", "finally"], ["keyword", "long"],
 	["keyword", "strictfp"], ["keyword", "volatile"], ["keyword", "const"],
-	["keyword", "float"], ["keyword", "native"], ["keyword", "super"], ["keyword", "while"]
+	["keyword", "float"], ["keyword", "native"], ["keyword", "super"], ["keyword", "while"],
+	["keyword", "var"], ["keyword", "null"]
 ]
 
 ----------------------------------------------------
 
-Checks for all keywords.
+Checks for all keywords.

tests/languages/java/number_feature.test

@@ -1,27 +1,60 @@
-0b11110000
-0xBadFace
-0x1.8p1
-0xa.fp-2
 42
 42d
+42L
+
 1.2e3f
 0.1E-4f
 0.2e+1f
 
+0xBadFace
+
+0x1.8p1
+0xa.fp-2
+0xa.fp+2
+0xa.p+3f
+0x.fp+3f
+
+0b11110000
+
+1_2_3
+1_2.3_4e-5_6
+
+0x1_2
+0x0_1__2_3
+
+0b1_1_1_1__0_0_0_0
+
+
 ----------------------------------------------------
 
 [
-	["number", "0b11110000"],
-	["number", "0xBadFace"],
-	["number", "0x1.8p1"],
-	["number", "0xa.fp-2"],
 	["number", "42"],
 	["number", "42d"],
+	["number", "42L"],
+
 	["number", "1.2e3f"],
 	["number", "0.1E-4f"],
-	["number", "0.2e+1f"]
+	["number", "0.2e+1f"],
+
+	["number", "0xBadFace"],
+
+	["number", "0x1.8p1"],
+	["number", "0xa.fp-2"],
+	["number", "0xa.fp+2"],
+	["number", "0xa.p+3f"],
+	["number", "0x.fp+3f"],
+
+	["number", "0b11110000"],
+
+	["number", "1_2_3"],
+	["number", "1_2.3_4e-5_6"],
+
+	["number", "0x1_2"],
+	["number", "0x0_1__2_3"],
+
+	["number", "0b1_1_1_1__0_0_0_0"]
 ]
 
 ----------------------------------------------------
 
-Checks for binary, hexadecimal and decimal numbers.
+Checks for binary, hexadecimal and decimal numbers.