Add Java highlighting from Megaxela#38

CMakeLists.txt

@@ -24,6 +24,7 @@ set(INCLUDE_FILES
     include/QSyntaxStyle
     include/QGLSLCompleter
     include/QGLSLHighlighter
+    include/QJavaHighlighter
     include/QLanguage
     include/QXMLHighlighter
     include/QJSONHighlighter
@@ -34,6 +35,7 @@ set(INCLUDE_FILES
     include/internal/QHighlightBlockRule.hpp
     include/internal/QCodeEditor.hpp
     include/internal/QCXXHighlighter.hpp
+    include/internal/QJavaHighlighter.hpp
     include/internal/QLineNumberArea.hpp
     include/internal/QStyleSyntaxHighlighter.hpp
     include/internal/QSyntaxStyle.hpp
@@ -56,6 +58,7 @@ set(SOURCE_FILES
     src/internal/QStyleSyntaxHighlighter.cpp
     src/internal/QGLSLCompleter.cpp
     src/internal/QGLSLHighlighter.cpp
+    src/internal/QJavaHighlighter.cpp
     src/internal/QLanguage.cpp
     src/internal/QXMLHighlighter.cpp
     src/internal/QJSONHighlighter.cpp

example/resources/code_samples/java.java

@@ -0,0 +1,32 @@
+import java.util.Scanner;
+
+/* This program is simply for demonstrating
+ * the highlighting of Java syntax.
+ */
+
+class Animal { }
+
+class Dog extends Animal { }
+
+public class Example {
+  /** Prompts the user for a string and returns what they entered.
+   * @param message The message to display to the user.
+   * @return The string that the user entered.
+   * */
+  static String prompt(String message) {
+
+    Scanner scanner = new Scanner(System.in);
+
+    System.out.printf("%s: ", message);
+
+    return scanner.nextLine();
+  }
+  public static void main(String[] args) {
+
+    double pi = 3.1415;
+
+    String name = prompt("Enter your name");
+
+    System.out.println("Nice to meet you, " + name + "!");
+  }
+}

example/resources/demo_resources.qrc

@@ -4,6 +4,7 @@
         <file>code_samples/cxx.cpp</file>
         <file>code_samples/shader.glsl</file>
         <file>code_samples/xml.xml</file>
+        <file>code_samples/java.java</file>
         <file>code_samples/json.json</file>
         <file>code_samples/lua.lua</file>
         <file>code_samples/python.py</file>

example/src/MainWindow.cpp

@@ -10,6 +10,7 @@
 #include <QCXXHighlighter>
 #include <QGLSLHighlighter>
 #include <QXMLHighlighter>
+#include <QJavaHighlighter>
 #include <QJSONHighlighter>
 #include <QLuaHighlighter>
 #include <QPythonHighlighter>
@@ -53,6 +54,7 @@ void MainWindow::initData()
         {"C++",  loadCode(":/code_samples/cxx.cpp")},
         {"GLSL", loadCode(":/code_samples/shader.glsl")},
         {"XML",  loadCode(":/code_samples/xml.xml")},
+        {"Java",  loadCode(":/code_samples/java.java")},
         {"JSON",  loadCode(":/code_samples/json.json")},
         {"LUA",  loadCode(":/code_samples/lua.lua")},
         {"Python",  loadCode(":/code_samples/python.py")}
@@ -70,6 +72,7 @@ void MainWindow::initData()
         {"C++",  new QCXXHighlighter},
         {"GLSL", new QGLSLHighlighter},
         {"XML",  new QXMLHighlighter},
+        {"Java", new QJavaHighlighter },
         {"JSON", new QJSONHighlighter},
         {"LUA",  new QLuaHighlighter},
         {"Python",  new QPythonHighlighter},

include/QJavaHighlighter

@@ -0,0 +1,3 @@
+#pragma once
+
+#include <internal/QJavaHighlighter.hpp>

include/internal/QJavaHighlighter.hpp

@@ -0,0 +1,42 @@
+#pragma once
+
+// QCodeEditor
+#include <QStyleSyntaxHighlighter> // Required for inheritance
+#include <QHighlightRule>
+
+// Qt
+#include <QRegularExpression>
+#include <QVector>
+
+class QSyntaxStyle;
+
+/**
+ * @brief Derived to implement highlighting of Java code.
+ */
+class QJavaHighlighter : public QStyleSyntaxHighlighter
+{
+    Q_OBJECT
+public:
+
+    /**
+     * @brief Constructs a new instance of a Java highlighter.
+     * @param document The text document to be highlighted.
+     * This may be a null pointer.
+     */
+    explicit QJavaHighlighter(QTextDocument* document=nullptr);
+
+protected:
+    /**
+     * @brief Derived to highlight blocks of Java code.
+     * @param text The block of text containing Java code.
+     */
+    void highlightBlock(const QString& text) override;
+
+private:
+
+    QVector<QHighlightRule> m_highlightRules;
+
+    QRegularExpression m_commentStartPattern;
+    QRegularExpression m_commentEndPattern;
+};
+

resources/languages/glsl.xml

@@ -351,4 +351,4 @@
         <name>iimage2DMSArray</name>
         <name>uimage2DMSArray</name>
     </section>
-</root>
+</root>

resources/languages/java.xml

@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<root>
+    <section name="Keyword">
+        <name>abstract</name>
+        <name>assert</name>
+        <name>break</name>
+        <name>case</name>
+        <name>catch</name>
+        <name>const</name>
+        <name>continue</name>
+        <name>default</name>
+        <name>do</name>
+        <name>else</name>
+        <name>extends</name>
+        <name>final</name>
+        <name>finally</name>
+        <name>for</name>
+        <name>if</name>
+        <name>goto</name>
+        <name>implements</name>
+        <name>import</name>
+        <name>instanceof</name>
+        <name>native</name>
+        <name>new</name>
+        <name>package</name>
+        <name>private</name>
+        <name>protected</name>
+        <name>public</name>
+        <name>return</name>
+        <name>static</name>
+        <name>strictfp</name>
+        <name>super</name>
+        <name>switch</name>
+        <name>synchronized</name>
+        <name>this</name>
+        <name>throw</name>
+        <name>throws</name>
+        <name>transient</name>
+        <name>try</name>
+        <name>volatile</name>
+        <name>while</name>
+
+        <name>true</name>
+        <name>false</name>
+        <name>null</name>
+
+    </section>
+    <section name="PrimitiveType">
+        <name>boolean</name>
+        <name>byte</name>
+        <name>char</name>
+        <name>class</name>
+        <name>double</name>
+        <name>enum</name>
+        <name>float</name>
+        <name>int</name>
+        <name>interface</name>
+        <name>long</name>
+        <name>short</name>
+        <name>void</name>
+    </section>
+</root>

resources/qcodeeditor_resources.qrc

@@ -3,6 +3,7 @@
         <file>default_style.xml</file>
         <file>languages/glsl.xml</file>
         <file>languages/cpp.xml</file>
+        <file>languages/java.xml</file>
         <file>languages/lua.xml</file>
         <file>languages/python.xml</file>
     </qresource>

src/internal/QJavaHighlighter.cpp

@@ -0,0 +1,114 @@
+// QCodeEditor
+#include <QJavaHighlighter>
+#include <QSyntaxStyle>
+#include <QLanguage>
+
+// Qt
+#include <QFile>
+
+
+QJavaHighlighter::QJavaHighlighter(QTextDocument* document) :
+    QStyleSyntaxHighlighter(document),
+    m_highlightRules     (),
+    m_commentStartPattern(QRegularExpression(R"(/\*)")),
+    m_commentEndPattern  (QRegularExpression(R"(\*/)"))
+{
+    Q_INIT_RESOURCE(qcodeeditor_resources);
+
+    QFile fl(":/languages/java.xml");
+
+    if (!fl.open(QIODevice::ReadOnly))
+    {
+        return;
+    }
+
+    QLanguage language(&fl);
+
+    if (!language.isLoaded())
+    {
+        return;
+    }
+
+    auto keys = language.keys();
+    for (auto&& key : keys)
+    {
+        auto names = language.names(key);
+        for (auto&& name : names)
+        {
+            m_highlightRules.append({
+                QRegularExpression(QString(R"(\b%1\b)").arg(name)),
+                key
+            });
+        }
+    }
+
+    // Numbers
+    m_highlightRules.append({
+        QRegularExpression(R"((?<=\b|\s|^)(?i)(?:(?:(?:(?:(?:\d+(?:'\d+)*)?\.(?:\d+(?:'\d+)*)(?:e[+-]?(?:\d+(?:'\d+)*))?)|(?:(?:\d+(?:'\d+)*)\.(?:e[+-]?(?:\d+(?:'\d+)*))?)|(?:(?:\d+(?:'\d+)*)(?:e[+-]?(?:\d+(?:'\d+)*)))|(?:0x(?:[0-9a-f]+(?:'[0-9a-f]+)*)?\.(?:[0-9a-f]+(?:'[0-9a-f]+)*)(?:p[+-]?(?:\d+(?:'\d+)*)))|(?:0x(?:[0-9a-f]+(?:'[0-9a-f]+)*)\.?(?:p[+-]?(?:\d+(?:'\d+)*))))[lf]?)|(?:(?:(?:[1-9]\d*(?:'\d+)*)|(?:0[0-7]*(?:'[0-7]+)*)|(?:0x[0-9a-f]+(?:'[0-9a-f]+)*)|(?:0b[01]+(?:'[01]+)*))(?:u?l{0,2}|l{0,2}u?)))(?=\b|\s|$))"),
+        "Number"
+    });
+
+    // Strings
+    m_highlightRules.append({
+        QRegularExpression(R"("[^\n"]*")"),
+        "String"
+    });
+
+    // Single line
+    m_highlightRules.append({
+        QRegularExpression(R"(//[^\n]*)"),
+        "Comment"
+    });
+}
+
+void QJavaHighlighter::highlightBlock(const QString& text)
+{
+    for (auto& rule : m_highlightRules)
+    {
+        auto matchIterator = rule.pattern.globalMatch(text);
+
+        while (matchIterator.hasNext())
+        {
+            auto match = matchIterator.next();
+
+            setFormat(
+                match.capturedStart(),
+                match.capturedLength(),
+                syntaxStyle()->getFormat(rule.formatName)
+            );
+        }
+    }
+
+    setCurrentBlockState(0);
+
+    int startIndex = 0;
+    if (previousBlockState() != 1)
+    {
+        startIndex = text.indexOf(m_commentStartPattern);
+    }
+
+    while (startIndex >= 0)
+    {
+        auto match = m_commentEndPattern.match(text, startIndex);
+
+        int endIndex = match.capturedStart();
+        int commentLength = 0;
+
+        if (endIndex == -1)
+        {
+            setCurrentBlockState(1);
+            commentLength = text.length() - startIndex;
+        }
+        else
+        {
+            commentLength = endIndex - startIndex + match.capturedLength();
+        }
+
+        setFormat(
+            startIndex,
+            commentLength,
+            syntaxStyle()->getFormat("Comment")
+        );
+        startIndex = text.indexOf(m_commentStartPattern, startIndex + commentLength);
+    }
+}