Jackson exceptions should be Jackson-serializable

src/main/java/com/fasterxml/jackson/databind/JsonMappingException.java

@@ -454,6 +454,7 @@ public void prependPath(Reference r)
     /**********************************************************
      */
 
+    @JsonIgnore
     @Override // since 2.7.5
     public Object getProcessor() { return _processor; }
 

src/test/java/com/fasterxml/jackson/databind/TestJsonMappingException.java

@@ -0,0 +1,32 @@
+package com.fasterxml.jackson.databind;
+
+import java.io.IOException;
+
+import org.junit.Test;
+
+public class TestJsonMappingException {
+	public static class NoSerdeConstructor {
+		private String strVal;
+		public String getVal() { return strVal; }
+		public NoSerdeConstructor( String strVal ) {
+			this.strVal = strVal;
+		}
+	}
+	// we know we can't serialize this dumb class above
+	@Test( expected = JsonMappingException.class )
+	public void testNoSerdeConstructor() throws IOException {
+		ObjectMapper mpr = new ObjectMapper();
+		mpr.readValue( "{ \"val\": \"foo\" }", NoSerdeConstructor.class );
+	}
+	// we should, however, be able to serialize the exception arising from the above test
+	@Test
+	public void testJsonMappingExceptionIsJacksonSerializable() throws IOException {
+		ObjectMapper mpr = new ObjectMapper();
+		try {
+			testNoSerdeConstructor();
+		} catch ( JsonMappingException exc ) {
+			// without @JsonIgnore on getProcessor() this causes an error
+			mpr.writeValueAsString( exc );
+		}
+	}
+}