Fix #1301

Author: cowtowncoder

Diff for: release-notes/CREDITS

@@ -463,3 +463,7 @@ Andrew Joseph (apjoseph@github)
 Erich Schubert (kno10@github)
   * Reported #1260: `NullPointerException` in `JsonNodeDeserializer`, provided fix
    (2.7.5)
+
+Brian Pontarelli (voidmain@github)
+  * Reported #1301: Problem with `JavaType.toString()` for recursive (self-referential) types
+   (2.7.6)

Diff for: release-notes/VERSION

@@ -10,6 +10,8 @@ Project: jackson-databind
  (reported by brentryan@github)
 #1279: Ensure DOM parsing defaults to not expanding external entities
 #1288: Type id not exposed for `JsonTypeInfo.As.EXTERNAL_PROPERTY` even when `visible` set to `true`
+#1301: Problem with `JavaType.toString()` for recursive (self-referential) types
+ (reported by Brian P)
 
 2.7.5 (11-Jun-2016)
 

Diff for: src/main/java/com/fasterxml/jackson/databind/type/ResolvedRecursiveType.java

@@ -87,11 +87,16 @@ public boolean isContainerType() {
 
     @Override
     public String toString() {
-        return new StringBuilder(40)
-        .append("[resolved recursive type -> ")
-        .append(_referencedType)
-        .append(']')
-        .toString();
+        StringBuilder sb = new StringBuilder(40)
+                .append("[recursive type; ");
+        if (_referencedType == null) {
+            sb.append("UNRESOLVED");
+        } else {
+            // [databind#1301]: Typically resolves to a loop so short-cut
+            //   and only include type-erased class
+            sb.append(_referencedType.getRawClass().getName());
+        }
+        return sb.toString();
     }
 
     @Override

Diff for: src/test/java/com/fasterxml/jackson/failing/JavaTypeDesc1301Test.java

@@ -0,0 +1,33 @@
+package com.fasterxml.jackson.failing;
+
+import java.util.HashMap;
+
+import com.fasterxml.jackson.databind.BaseMapTest;
+import com.fasterxml.jackson.databind.type.TypeFactory;
+
+@SuppressWarnings("serial")
+public class JavaTypeDesc1301Test extends BaseMapTest
+{
+    static class DataDefinition extends HashMap<String, DataDefinition> {
+        public DataDefinition definition;
+        public DataDefinition elements;
+        public String regex;
+        public boolean required;
+        public String type;
+    }
+
+    // for [databind#1301]
+    public void testJavaTypeToString() throws Exception
+    {
+        TypeFactory tf = objectMapper().getTypeFactory();
+        String desc = tf.constructType(DataDefinition.class).toString();
+        assertNotNull(desc);
+        // could try comparing exact message, but since it's informational try looser:
+        if (!desc.contains("map type")) {
+            fail("Description should contain 'map type', did not: "+desc);
+        }
+        if (!desc.contains("recursive type")) {
+            fail("Description should contain 'recursive type', did not: "+desc);
+        }
+    }
+}