Clean up usages of some old Java APIs

README.md

@@ -196,7 +196,7 @@ class IndentedCodeBlockNodeRenderer implements NodeRenderer {
     @Override
     public Set<Class<? extends Node>> getNodeTypes() {
         // Return the node types we want to use this renderer for.
-        return Collections.<Class<? extends Node>>singleton(IndentedCodeBlock.class);
+        return Set.of(IndentedCodeBlock.class);
     }
 
     @Override
@@ -274,7 +274,7 @@ Then, configure the extension on the builders:
 ```java
 import org.commonmark.ext.gfm.tables.TablesExtension;
 
-List<Extension> extensions = Arrays.asList(TablesExtension.create());
+List<Extension> extensions = List.of(TablesExtension.create());
 Parser parser = Parser.builder()
         .extensions(extensions)
         .build();

commonmark-ext-autolink/src/test/java/org/commonmark/ext/autolink/AutolinkTest.java

@@ -8,17 +8,15 @@
 import org.commonmark.testutil.RenderingTestCase;
 import org.junit.Test;
 
-import java.util.Arrays;
-import java.util.Collections;
+import java.util.List;
 import java.util.Set;
 
-import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
 public class AutolinkTest extends RenderingTestCase {
 
-    private static final Set<Extension> EXTENSIONS = Collections.singleton(AutolinkExtension.create());
+    private static final Set<Extension> EXTENSIONS = Set.of(AutolinkExtension.create());
     private static final Parser PARSER = Parser.builder().extensions(EXTENSIONS).build();
     private static final HtmlRenderer RENDERER = HtmlRenderer.builder().extensions(EXTENSIONS).build();
 
@@ -73,43 +71,43 @@ public void sourceSpans() {
 
         Paragraph paragraph = (Paragraph) document.getFirstChild();
         Text abc = (Text) paragraph.getFirstChild();
-        assertEquals(Arrays.asList(SourceSpan.of(0, 0, 3)),
+        assertEquals(List.of(SourceSpan.of(0, 0, 3)),
                 abc.getSourceSpans());
 
         assertTrue(abc.getNext() instanceof SoftLineBreak);
 
         Link one = (Link) abc.getNext().getNext();
         assertEquals("http://example.com/one", one.getDestination());
-        assertEquals(Arrays.asList(SourceSpan.of(1, 0, 22)),
+        assertEquals(List.of(SourceSpan.of(1, 0, 22)),
                 one.getSourceSpans());
 
         assertTrue(one.getNext() instanceof SoftLineBreak);
 
         Text def = (Text) one.getNext().getNext();
         assertEquals("def ", def.getLiteral());
-        assertEquals(Arrays.asList(SourceSpan.of(2, 0, 4)),
+        assertEquals(List.of(SourceSpan.of(2, 0, 4)),
                 def.getSourceSpans());
 
         Link two = (Link) def.getNext();
         assertEquals("http://example.com/two", two.getDestination());
-        assertEquals(Arrays.asList(SourceSpan.of(2, 4, 22)),
+        assertEquals(List.of(SourceSpan.of(2, 4, 22)),
                 two.getSourceSpans());
 
         assertTrue(two.getNext() instanceof SoftLineBreak);
 
         Text ghi = (Text) two.getNext().getNext();
         assertEquals("ghi ", ghi.getLiteral());
-        assertEquals(Arrays.asList(SourceSpan.of(3, 0, 4)),
+        assertEquals(List.of(SourceSpan.of(3, 0, 4)),
                 ghi.getSourceSpans());
 
         Link three = (Link) ghi.getNext();
         assertEquals("http://example.com/three", three.getDestination());
-        assertEquals(Arrays.asList(SourceSpan.of(3, 4, 24)),
+        assertEquals(List.of(SourceSpan.of(3, 4, 24)),
                 three.getSourceSpans());
 
         Text jkl = (Text) three.getNext();
         assertEquals(" jkl", jkl.getLiteral());
-        assertEquals(Arrays.asList(SourceSpan.of(3, 28, 4)),
+        assertEquals(List.of(SourceSpan.of(3, 28, 4)),
                 jkl.getSourceSpans());
     }
 

commonmark-ext-gfm-strikethrough/src/main/java/org/commonmark/ext/gfm/strikethrough/StrikethroughExtension.java

@@ -17,7 +17,6 @@
 import org.commonmark.renderer.text.TextContentNodeRendererFactory;
 import org.commonmark.renderer.text.TextContentRenderer;
 
-import java.util.Collections;
 import java.util.Set;
 
 /**
@@ -106,7 +105,7 @@ public NodeRenderer create(MarkdownNodeRendererContext context) {
 
             @Override
             public Set<Character> getSpecialCharacters() {
-                return Collections.singleton('~');
+                return Set.of('~');
             }
         });
     }

commonmark-ext-gfm-strikethrough/src/main/java/org/commonmark/ext/gfm/strikethrough/internal/StrikethroughHtmlNodeRenderer.java

@@ -1,10 +1,9 @@
 package org.commonmark.ext.gfm.strikethrough.internal;
 
-import org.commonmark.renderer.html.HtmlWriter;
-import org.commonmark.renderer.html.HtmlNodeRendererContext;
 import org.commonmark.node.Node;
+import org.commonmark.renderer.html.HtmlNodeRendererContext;
+import org.commonmark.renderer.html.HtmlWriter;
 
-import java.util.Collections;
 import java.util.Map;
 
 public class StrikethroughHtmlNodeRenderer extends StrikethroughNodeRenderer {
@@ -19,7 +18,7 @@ public StrikethroughHtmlNodeRenderer(HtmlNodeRendererContext context) {
 
     @Override
     public void render(Node node) {
-        Map<String, String> attributes = context.extendAttributes(node, "del", Collections.<String, String>emptyMap());
+        Map<String, String> attributes = context.extendAttributes(node, "del", Map.of());
         html.tag("del", attributes);
         renderChildren(node);
         html.tag("/del");

commonmark-ext-gfm-strikethrough/src/main/java/org/commonmark/ext/gfm/strikethrough/internal/StrikethroughNodeRenderer.java

@@ -4,13 +4,12 @@
 import org.commonmark.node.Node;
 import org.commonmark.renderer.NodeRenderer;
 
-import java.util.Collections;
 import java.util.Set;
 
 abstract class StrikethroughNodeRenderer implements NodeRenderer {
 
     @Override
     public Set<Class<? extends Node>> getNodeTypes() {
-        return Collections.<Class<? extends Node>>singleton(Strikethrough.class);
+        return Set.of(Strikethrough.class);
     }
 }

commonmark-ext-gfm-strikethrough/src/test/java/org/commonmark/ext/gfm/strikethrough/StrikethroughMarkdownRendererTest.java

@@ -5,14 +5,13 @@
 import org.commonmark.renderer.markdown.MarkdownRenderer;
 import org.junit.Test;
 
-import java.util.Collections;
 import java.util.Set;
 
 import static org.junit.Assert.assertEquals;
 
 public class StrikethroughMarkdownRendererTest {
 
-    private static final Set<Extension> EXTENSIONS = Collections.singleton(StrikethroughExtension.create());
+    private static final Set<Extension> EXTENSIONS = Set.of(StrikethroughExtension.create());
     private static final Parser PARSER = Parser.builder().extensions(EXTENSIONS).build();
     private static final MarkdownRenderer RENDERER = MarkdownRenderer.builder().extensions(EXTENSIONS).build();
 

commonmark-ext-gfm-strikethrough/src/test/java/org/commonmark/ext/gfm/strikethrough/StrikethroughSpecTest.java

@@ -12,14 +12,13 @@
 import org.junit.runners.Parameterized;
 import org.junit.runners.Parameterized.Parameters;
 
-import java.util.Collections;
 import java.util.List;
 import java.util.Set;
 
 @RunWith(Parameterized.class)
 public class StrikethroughSpecTest extends RenderingTestCase {
 
-    private static final Set<Extension> EXTENSIONS = Collections.singleton(StrikethroughExtension.create());
+    private static final Set<Extension> EXTENSIONS = Set.of(StrikethroughExtension.create());
     private static final Parser PARSER = Parser.builder().extensions(EXTENSIONS).build();
     private static final HtmlRenderer RENDERER = HtmlRenderer.builder().extensions(EXTENSIONS).build();
 

commonmark-ext-gfm-strikethrough/src/test/java/org/commonmark/ext/gfm/strikethrough/StrikethroughTest.java

@@ -14,15 +14,14 @@
 import org.commonmark.testutil.RenderingTestCase;
 import org.junit.Test;
 
-import java.util.Arrays;
+import java.util.List;
 import java.util.Set;
 
-import static java.util.Collections.singleton;
 import static org.junit.Assert.assertEquals;
 
 public class StrikethroughTest extends RenderingTestCase {
 
-    private static final Set<Extension> EXTENSIONS = singleton(StrikethroughExtension.create());
+    private static final Set<Extension> EXTENSIONS = Set.of(StrikethroughExtension.create());
     private static final Parser PARSER = Parser.builder().extensions(EXTENSIONS).build();
     private static final HtmlRenderer HTML_RENDERER = HtmlRenderer.builder().extensions(EXTENSIONS).build();
     private static final TextContentRenderer CONTENT_RENDERER = TextContentRenderer.builder()
@@ -98,7 +97,7 @@ public void textContentRenderer() {
     @Test
     public void requireTwoTildesOption() {
         Parser parser = Parser.builder()
-                .extensions(singleton(StrikethroughExtension.builder()
+                .extensions(Set.of(StrikethroughExtension.builder()
                         .requireTwoTildes(true)
                         .build()))
                 .customDelimiterProcessor(new SubscriptDelimiterProcessor())
@@ -118,7 +117,7 @@ public void sourceSpans() {
         Node document = parser.parse("hey ~~there~~\n");
         Paragraph block = (Paragraph) document.getFirstChild();
         Node strikethrough = block.getLastChild();
-        assertEquals(Arrays.asList(SourceSpan.of(0, 4, 9)),
+        assertEquals(List.of(SourceSpan.of(0, 4, 9)),
                 strikethrough.getSourceSpans());
     }
 

commonmark-ext-gfm-tables/src/main/java/org/commonmark/ext/gfm/tables/TablesExtension.java

@@ -17,7 +17,6 @@
 import org.commonmark.renderer.text.TextContentNodeRendererFactory;
 import org.commonmark.renderer.text.TextContentRenderer;
 
-import java.util.Collections;
 import java.util.Set;
 
 /**
@@ -78,7 +77,7 @@ public NodeRenderer create(MarkdownNodeRendererContext context) {
 
             @Override
             public Set<Character> getSpecialCharacters() {
-                return Collections.singleton('|');
+                return Set.of('|');
             }
         });
     }

commonmark-ext-gfm-tables/src/main/java/org/commonmark/ext/gfm/tables/internal/TableHtmlNodeRenderer.java

@@ -5,7 +5,6 @@
 import org.commonmark.renderer.html.HtmlNodeRendererContext;
 import org.commonmark.renderer.html.HtmlWriter;
 
-import java.util.Collections;
 import java.util.Map;
 
 public class TableHtmlNodeRenderer extends TableNodeRenderer {
@@ -60,14 +59,14 @@ protected void renderCell(TableCell tableCell) {
     }
 
     private Map<String, String> getAttributes(Node node, String tagName) {
-        return context.extendAttributes(node, tagName, Collections.<String, String>emptyMap());
+        return context.extendAttributes(node, tagName, Map.of());
     }
 
     private Map<String, String> getCellAttributes(TableCell tableCell, String tagName) {
         if (tableCell.getAlignment() != null) {
-            return context.extendAttributes(tableCell, tagName, Collections.singletonMap("align", getAlignValue(tableCell.getAlignment())));
+            return context.extendAttributes(tableCell, tagName, Map.of("align", getAlignValue(tableCell.getAlignment())));
         } else {
-            return context.extendAttributes(tableCell, tagName, Collections.<String, String>emptyMap());
+            return context.extendAttributes(tableCell, tagName, Map.of());
         }
     }
 

commonmark-ext-gfm-tables/src/main/java/org/commonmark/ext/gfm/tables/internal/TableNodeRenderer.java

@@ -1,28 +1,22 @@
 package org.commonmark.ext.gfm.tables.internal;
 
-import java.util.Arrays;
-import java.util.HashSet;
-import java.util.Set;
-
-import org.commonmark.ext.gfm.tables.TableBlock;
-import org.commonmark.ext.gfm.tables.TableBody;
-import org.commonmark.ext.gfm.tables.TableCell;
-import org.commonmark.ext.gfm.tables.TableHead;
-import org.commonmark.ext.gfm.tables.TableRow;
+import org.commonmark.ext.gfm.tables.*;
 import org.commonmark.node.Node;
 import org.commonmark.renderer.NodeRenderer;
 
+import java.util.Set;
+
 abstract class TableNodeRenderer implements NodeRenderer {
 
     @Override
     public Set<Class<? extends Node>> getNodeTypes() {
-        return new HashSet<>(Arrays.asList(
+        return Set.of(
                 TableBlock.class,
                 TableHead.class,
                 TableBody.class,
                 TableRow.class,
                 TableCell.class
-        ));
+        );
     }
 
     @Override

commonmark-ext-gfm-tables/src/test/java/org/commonmark/ext/gfm/tables/TableMarkdownRendererTest.java

@@ -5,14 +5,13 @@
 import org.commonmark.renderer.markdown.MarkdownRenderer;
 import org.junit.Test;
 
-import java.util.Collections;
 import java.util.Set;
 
 import static org.junit.Assert.assertEquals;
 
 public class TableMarkdownRendererTest {
 
-    private static final Set<Extension> EXTENSIONS = Collections.singleton(TablesExtension.create());
+    private static final Set<Extension> EXTENSIONS = Set.of(TablesExtension.create());
     private static final Parser PARSER = Parser.builder().extensions(EXTENSIONS).build();
     private static final MarkdownRenderer RENDERER = MarkdownRenderer.builder().extensions(EXTENSIONS).build();
 

commonmark-ext-gfm-tables/src/test/java/org/commonmark/ext/gfm/tables/TablesSpecTest.java

@@ -12,15 +12,13 @@
 import org.junit.runners.Parameterized;
 import org.junit.runners.Parameterized.Parameters;
 
-import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.Set;
 
 @RunWith(Parameterized.class)
 public class TablesSpecTest extends RenderingTestCase {
 
-    private static final Set<Extension> EXTENSIONS = Collections.singleton(TablesExtension.create());
+    private static final Set<Extension> EXTENSIONS = Set.of(TablesExtension.create());
     private static final Parser PARSER = Parser.builder().extensions(EXTENSIONS).build();
     private static final HtmlRenderer RENDERER = HtmlRenderer.builder().extensions(EXTENSIONS).build();