Java tutorial
/** * Copyright 2005-2016 Red Hat, Inc. * * Red Hat licenses this file to you under the Apache License, version * 2.0 (the "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or * implied. See the License for the specific language governing * permissions and limitations under the License. */ package io.fabric8.cxf.endpoint; import java.util.logging.Level; import java.util.logging.Logger; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.ObjectWriter; import com.fasterxml.jackson.module.jaxb.JaxbAnnotationModule; import com.fasterxml.jackson.module.jsonSchema.JsonSchema; import com.fasterxml.jackson.module.jsonSchema.JsonSchemaGenerator; import org.apache.cxf.common.logging.LogUtils; public class JsonSchemaLookup { private static final Logger LOG = LogUtils.getL7dLogger(JsonSchemaLookup.class); private static JsonSchemaLookup singleton; private ObjectMapper mapper; public JsonSchemaLookup() { } public static JsonSchemaLookup getSingleton() { if (singleton == null) { // lazy create one new JsonSchemaLookup().init(); } return singleton; } public void init() { LOG.log(Level.INFO, "Creating JsonSchemaLookup instance"); try { if (mapper == null) { mapper = new ObjectMapper(); mapper.setVisibility(new IgnorePropertiesBackedByTransientFields(mapper.getVisibilityChecker())); JaxbAnnotationModule module1 = new JaxbAnnotationModule(); mapper.registerModule(module1); BeanValidationAnnotationModule module2 = new BeanValidationAnnotationModule(); mapper.registerModule(module2); } // now lets expose the mbean... singleton = this; } catch (Exception e) { LOG.log(Level.WARNING, "Exception during initialization: ", e); throw new RuntimeException(e); } } public String getSchemaForClass(Class<?> clazz) { LOG.info("Looking up schema for " + clazz.getCanonicalName()); String name = clazz.getName(); try { ObjectWriter writer = mapper.writer().with(new FourSpacePrettyPrinter()); JsonSchemaGenerator jsg = new JsonSchemaGenerator(mapper); JsonSchema jsonSchema = jsg.generateSchema(clazz); return writer.writeValueAsString(jsonSchema); } catch (Exception e) { LOG.log(Level.FINEST, "Failed to generate JSON schema for class " + name, e); return ""; } } public ObjectMapper getMapper() { return mapper; } public void setMapper(ObjectMapper mapper) { this.mapper = mapper; } }