BAEL-1990: IntelliJ plugin example (eugenp#4942)

* Initial revision

* Add actions and plugin config

* Add language tag to search action

* Cleanup before submitting

intelliJ/stackoverflow-plugin/resources/META-INF/plugin.xml

@@ -0,0 +1,62 @@
+<idea-plugin>
+  <id>com.baeldung.intellij.stackoverflowplugin</id>
+  <name>Stack Overflow Plugin for IntelliJ</name>
+  <version>1.0</version>
+  <vendor email="[email protected]" url="http://www.baeldung.com">Baeldung</vendor>
+
+  <description><![CDATA[
+      Plugin to help search Stack Overflow from inside IntelliJ
+    ]]></description>
+
+  <change-notes><![CDATA[
+      <ul>
+        <li>1.0 - Initial release</li>
+      </ul>
+    ]]>
+  </change-notes>
+
+  <!-- please see http://www.jetbrains.org/intellij/sdk/docs/basics/getting_started/build_number_ranges.html for description -->
+  <idea-version since-build="173.0"/>
+
+  <!-- please see http://www.jetbrains.org/intellij/sdk/docs/basics/getting_started/plugin_compatibility.html
+       on how to target different products -->
+  <!-- uncomment to enable plugin in all products
+  <depends>com.intellij.modules.lang</depends>
+  -->
+
+  <extensions defaultExtensionNs="com.intellij">
+    <!-- Add your extensions here -->
+  </extensions>
+
+  <actions>
+
+    <!-- Add Ask question action to Tools Menu -->
+    <action id="StackOverflow.AskQuestion.ToolsMenu"
+            class="com.baeldung.intellij.stackoverflowplugin.AskQuestionAction"
+            text="Ask Question on Stack Overflow"
+            icon="so-icon-16x16.png"
+            description="Ask a Question on Stack Overflow">
+      <add-to-group group-id="ToolsMenu" anchor="last"/>
+    </action>
+
+    <!-- Add action to search Stack Overflow from file editor -->
+    <action id="StackOverflow.Search.Editor"
+            class="com.baeldung.intellij.stackoverflowplugin.SearchAction"
+            text="Search on Stack Overflow"
+            icon="so-icon-16x16.png"
+            description="Search on Stack Overflow">
+      <add-to-group group-id="EditorPopupMenu" anchor="last"/>
+    </action>
+
+    <!-- Add action to search Stack Overflow from console editor -->
+    <action id="StackOverflow.Search.Console"
+            class="com.baeldung.intellij.stackoverflowplugin.SearchAction"
+            text="Search on Stack Overflow"
+            icon="so-icon-16x16.png"
+            description="Search on Stack Overflow">
+      <add-to-group group-id="ConsoleEditorPopupMenu" anchor="last"/>
+    </action>
+
+  </actions>
+
+</idea-plugin>

intelliJ/stackoverflow-plugin/src/com/baeldung/intellij/stackoverflowplugin/AskQuestionAction.java

@@ -0,0 +1,14 @@
+package com.baeldung.intellij.stackoverflowplugin;
+
+import com.intellij.ide.BrowserUtil;
+import com.intellij.openapi.actionSystem.AnAction;
+import com.intellij.openapi.actionSystem.AnActionEvent;
+
+public class AskQuestionAction extends AnAction
+{
+   @Override
+   public void actionPerformed(AnActionEvent e)
+   {
+      BrowserUtil.browse("https://stackoverflow.com/questions/ask");
+   }
+}

intelliJ/stackoverflow-plugin/src/com/baeldung/intellij/stackoverflowplugin/SearchAction.java

@@ -0,0 +1,58 @@
+package com.baeldung.intellij.stackoverflowplugin;
+
+import com.intellij.ide.BrowserUtil;
+import com.intellij.lang.Language;
+import com.intellij.openapi.actionSystem.ActionManager;
+import com.intellij.openapi.actionSystem.AnAction;
+import com.intellij.openapi.actionSystem.AnActionEvent;
+import com.intellij.openapi.actionSystem.CommonDataKeys;
+import com.intellij.openapi.editor.CaretModel;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.psi.PsiFile;
+
+public class SearchAction extends AnAction
+{
+   /**
+    * Convert selected text to a URL friendly string.
+    * @param e
+    */
+   @Override
+   public void actionPerformed(AnActionEvent e)
+   {
+      final Editor editor = e.getRequiredData(CommonDataKeys.EDITOR);
+      CaretModel caretModel = editor.getCaretModel();
+
+      // For searches from the editor, we should also get file type information
+      // to help add scope to the search using the Stack overflow search syntax.
+      //
+      // https://stackoverflow.com/help/searching
+
+      String languageTag = "";
+      PsiFile file = e.getData(CommonDataKeys.PSI_FILE);
+      if(file != null)
+      {
+         Language lang = e.getData(CommonDataKeys.PSI_FILE).getLanguage();
+         languageTag = "+[" + lang.getDisplayName().toLowerCase() + "]";
+      }
+
+      // The update method below is only called periodically so need
+      // to be careful to check for selected text
+      if(caretModel.getCurrentCaret().hasSelection())
+      {
+         String query = caretModel.getCurrentCaret().getSelectedText().replace(' ', '+') + languageTag;
+         BrowserUtil.browse("https://stackoverflow.com/search?q=" + query);
+      }
+   }
+
+   /**
+    * Only make this action visible when text is selected.
+    * @param e
+    */
+   @Override
+   public void update(AnActionEvent e)
+   {
+      final Editor editor = e.getRequiredData(CommonDataKeys.EDITOR);
+      CaretModel caretModel = editor.getCaretModel();
+      e.getPresentation().setEnabledAndVisible(caretModel.getCurrentCaret().hasSelection());
+   }
+}