document bean handling of empty/missing params

Author: jknack

coverage-report/src/test/java/org/jooby/issues/Issue483.java

@@ -0,0 +1,47 @@
+package org.jooby.issues;
+
+import java.util.Optional;
+
+import org.jooby.Parser;
+import org.jooby.test.ServerFeature;
+import org.junit.Test;
+
+public class Issue483 extends ServerFeature {
+
+  public static class NullableBean {
+
+    String foo;
+
+    Optional<String> bar;
+
+    @Override
+    public String toString() {
+      return foo + bar;
+    }
+  }
+
+  {
+    parser(Parser.bean(true));
+
+    get("/483", req -> {
+      return req.params(NullableBean.class).toString();
+    });
+
+  }
+
+  @Test
+  public void documentNullBeanInjection() throws Exception {
+    request()
+        .get("/483?foo=foo")
+        .expect("foonull");
+
+    request()
+        .get("/483?foo=foo&bar")
+        .expect("fooOptional[]");
+
+    request()
+        .get("/483?foo=foo&bar=bar")
+        .expect("fooOptional[bar]");
+  }
+
+}