Exception when a class of the schema has a "static final" field

[AntwaneB]

Hello,

It seems like there's an issue handling "static final" fields for the models in the schema. For example, I'm getting the following exception when trying to parse a class that has a field of type Calendar:

java.lang.IllegalStateException: Could not access method: Class org.springframework.util.ReflectionUtils can not access a member of class java.util.Calendar with modifiers "static final"
    at org.springframework.util.ReflectionUtils.handleReflectionException(ReflectionUtils.java:277) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at org.springframework.util.ReflectionUtils.getField(ReflectionUtils.java:146) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.getFieldDefinition(GraphQLSchemaDfsTraversal.java:293) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.lambda$createGraphQLObjectTypeRecursively$1(GraphQLSchemaDfsTraversal.java:142) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_74]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLObjectTypeRecursively(GraphQLSchemaDfsTraversal.java:141) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLFieldType(GraphQLSchemaDfsTraversal.java:317) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.getFieldDefinition(GraphQLSchemaDfsTraversal.java:284) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.lambda$createGraphQLObjectTypeRecursively$1(GraphQLSchemaDfsTraversal.java:142) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_74]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLObjectTypeRecursively(GraphQLSchemaDfsTraversal.java:141) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLFieldType(GraphQLSchemaDfsTraversal.java:317) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.getFieldDefinition(GraphQLSchemaDfsTraversal.java:284) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.lambda$createGraphQLObjectTypeRecursively$1(GraphQLSchemaDfsTraversal.java:142) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_74]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLObjectTypeRecursively(GraphQLSchemaDfsTraversal.java:141) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLFieldType(GraphQLSchemaDfsTraversal.java:317) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.getFieldDefinition(GraphQLSchemaDfsTraversal.java:284) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.lambda$createGraphQLObjectTypeRecursively$1(GraphQLSchemaDfsTraversal.java:142) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_74]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLObjectTypeRecursively(GraphQLSchemaDfsTraversal.java:141) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLFieldType(GraphQLSchemaDfsTraversal.java:317) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.getFieldDefinition(GraphQLSchemaDfsTraversal.java:284) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.lambda$createGraphQLObjectTypeRecursively$1(GraphQLSchemaDfsTraversal.java:142) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_74]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLObjectTypeRecursively(GraphQLSchemaDfsTraversal.java:141) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLFieldType(GraphQLSchemaDfsTraversal.java:317) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.getFieldDefinition(GraphQLSchemaDfsTraversal.java:284) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.lambda$createGraphQLObjectTypeRecursively$1(GraphQLSchemaDfsTraversal.java:142) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_74]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLObjectTypeRecursively(GraphQLSchemaDfsTraversal.java:141) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLFieldType(GraphQLSchemaDfsTraversal.java:317) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.getMethodDefinition(GraphQLSchemaDfsTraversal.java:252) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.lambda$createGraphQLObjectTypeRecursively$2(GraphQLSchemaDfsTraversal.java:148) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_74]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.createGraphQLObjectTypeRecursively(GraphQLSchemaDfsTraversal.java:147) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.findSchemaQueryRoot(GraphQLSchemaDfsTraversal.java:120) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.dfs.GraphQLSchemaDfsTraversal.traverse(GraphQLSchemaDfsTraversal.java:100) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]
    at com.oembedler.moon.graphql.engine.GraphQLSchemaBuilder.buildSchema(GraphQLSchemaBuilder.java:51) ~[spring-graphql-common-2.1.0-2016-05-22T16-50-32.jar:na]