generic Renderer for render targets richer than String

commonmark/src/main/java/org/commonmark/renderer/Renderer.java

@@ -2,7 +2,7 @@
 
 import org.commonmark.node.Node;
 
-public interface Renderer {
+public interface Renderer<T> {
 
     /**
      * Render the tree of nodes to output.
@@ -16,7 +16,7 @@ public interface Renderer {
      * Render the tree of nodes to string.
      *
      * @param node the root node
-     * @return the rendered string
+     * @return the rendered result
      */
-    String render(Node node);
+    T render(Node node);
 }

commonmark/src/main/java/org/commonmark/renderer/html/HtmlRenderer.java

@@ -18,7 +18,7 @@
  * renderer.render(node);
  * </code></pre>
  */
-public class HtmlRenderer implements Renderer {
+public class HtmlRenderer implements Renderer<String> {
 
     private final String softbreak;
     private final boolean escapeHtml;

commonmark/src/main/java/org/commonmark/renderer/markdown/MarkdownRenderer.java

@@ -22,7 +22,7 @@
  * However, it should produce Markdown that is semantically equivalent to the input, i.e. if the Markdown was parsed
  * again and compared against the original AST, it should be the same (minus bugs).
  */
-public class MarkdownRenderer implements Renderer {
+public class MarkdownRenderer implements Renderer<String> {
 
     private final List<MarkdownNodeRendererFactory> nodeRendererFactories;
 

commonmark/src/main/java/org/commonmark/renderer/text/TextContentRenderer.java

@@ -12,7 +12,7 @@
 /**
  * Renders nodes to plain text content with minimal markup-like additions.
  */
-public class TextContentRenderer implements Renderer {
+public class TextContentRenderer implements Renderer<String> {
 
     private final LineBreakRendering lineBreakRendering;