content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF 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 org.apache.camel.component.jackson.transform;
  
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.Optional;
  
  import com.fasterxml.jackson.core.FormatSchema;
  import org.apache.camel.CamelContext;
  import org.apache.camel.CamelContextAware;
  import org.apache.camel.CamelExecutionException;
  import org.apache.camel.Exchange;
  import org.apache.camel.InvalidPayloadException;
  import org.apache.camel.Message;
  import org.apache.camel.component.jackson.SchemaHelper;
  import org.apache.camel.component.jackson.SchemaType;
  import org.apache.camel.spi.DataType;
  import org.apache.camel.spi.DataTypeTransformer;
  import org.apache.camel.spi.MimeType;
  import org.apache.camel.spi.Transformer;
  import org.apache.camel.util.ObjectHelper;
  
  /**
   * Data type able to unmarshal Exchange body to Java object. Supports both Json schema types and uses Jackson object
   * mapper implementation for the unmarshal operation. Requires proper setting of content schema, class and schema type
   * in Exchange properties (usually resolved via Json schema resolver).
   */
  @DataTypeTransformer(name = "application-x-java-object",
                       description = "Transforms from JSon to Java object using Jackson (supports content schema)")
  public class JsonPojoDataTypeTransformer extends Transformer implements CamelContextAware {
  
      private CamelContext camelContext;
  
      @Override
      public void transform(Message message, DataType fromType, DataType toType) {
          ObjectHelper.notNull(camelContext, "camelContext");
  
          FormatSchema schema = message.getExchange().getProperty(SchemaHelper.CONTENT_SCHEMA, FormatSchema.class);
          String contentClass = SchemaHelper.resolveContentClass(message.getExchange(), null);
          if (contentClass == null) {
              throw new CamelExecutionException(
                      "Missing content class information for Java object data type processing",
                      message.getExchange());
          }
  
          SchemaType schemaType = SchemaType.of(message.getExchange().getProperty(SchemaHelper.CONTENT_SCHEMA_TYPE,
                  Optional.ofNullable(schema).map(FormatSchema::getSchemaType).orElse(SchemaType.JSON.name()), String.class));
  
          try {
              message.setHeader(Exchange.CONTENT_TYPE, MimeType.JAVA_OBJECT.type());
  
              Class<?> contentType = camelContext.getClassResolver().resolveMandatoryClass(contentClass);
              if (contentType.isAssignableFrom(message.getBody().getClass())) {
                  return;
              }
  
              message.setBody(getJavaObject(message, schemaType, schema, contentType));
          } catch (InvalidPayloadException | IOException | ClassNotFoundException e) {
              throw new CamelExecutionException("Failed to apply Java object data type on exchange", message.getExchange(), e);
          }
      }
  
      protected Object getJavaObject(Message message, SchemaType schemaType, FormatSchema schema, Class<?> contentType)
              throws InvalidPayloadException, IOException {
          if (schemaType == SchemaType.JSON) {
              return Json.mapper().reader().forType(contentType).readValue(getBodyAsStream(message));
          } else {
              throw new CamelExecutionException(String.format("Unsupported schema type '%s'", schemaType), message.getExchange());
          }
      }
  
      protected InputStream getBodyAsStream(Message message) throws InvalidPayloadException {
          InputStream bodyStream = message.getBody(InputStream.class);
  
          if (bodyStream == null) {
              bodyStream = new ByteArrayInputStream(message.getMandatoryBody(byte[].class));
          }
  
          return bodyStream;
      }
  
      @Override
      public CamelContext getCamelContext() {
          return camelContext;
      }
  
      @Override
      public void setCamelContext(CamelContext camelContext) {
          this.camelContext = camelContext;
      }
  }
  