Ensure legal code mining types

Author: travkin79

bundles/org.eclipse.jface.text/src/org/eclipse/jface/internal/text/codemining/CodeMiningManager.java

@@ -280,6 +280,8 @@ private void renderCodeMinings(Map<Position, List<ICodeMining>> groups, ISourceV
 					mode= CodeMiningMode.HeaderLine;
 				} else if (CodeMiningMode.FooterLine.codeMiningType.isInstance(first)) {
 					mode= CodeMiningMode.FooterLine;
+				} else {
+					throw new IllegalStateException("Unexpected code mining type: " + first.getClass()); //$NON-NLS-1$
 				}
 			}
 

examples/org.eclipse.jface.text.examples/src/org/eclipse/jface/text/examples/codemining/MultilineCodeMiningProvider.java

@@ -19,9 +19,9 @@
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.Position;
-import org.eclipse.jface.text.codemining.AbstractCodeMining;
 import org.eclipse.jface.text.codemining.AbstractCodeMiningProvider;
 import org.eclipse.jface.text.codemining.ICodeMining;
+import org.eclipse.jface.text.codemining.LineContentCodeMining;
 import org.eclipse.jface.text.codemining.LineHeaderCodeMining;
 
 public class MultilineCodeMiningProvider extends AbstractCodeMiningProvider {
@@ -35,7 +35,7 @@ public CompletableFuture<List<? extends ICodeMining>> provideCodeMinings(ITextVi
 		int index = 0;
 		while ((index = document.get().indexOf(multiLineText, index)) != -1) {
 			index += multiLineText.length();
-			res.add(new AbstractCodeMining(new Position(index, 1), this, null) {
+			res.add(new LineContentCodeMining(new Position(index, 1), this, null) {
 				@Override
 				public String getLabel() {
 					return "multiline first part in same line";