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.converter;
  
  import java.io.ByteArrayInputStream;
  import java.io.File;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.Reader;
  import java.nio.ByteBuffer;
  import java.nio.charset.StandardCharsets;
  import java.util.Map;
  import java.util.Set;
  import java.util.concurrent.locks.Lock;
  import java.util.concurrent.locks.ReentrantLock;
  
  import com.fasterxml.jackson.core.type.TypeReference;
  import com.fasterxml.jackson.databind.JsonNode;
  import com.fasterxml.jackson.databind.Module;
  import com.fasterxml.jackson.databind.ObjectMapper;
  import com.fasterxml.jackson.databind.node.BooleanNode;
  import com.fasterxml.jackson.databind.node.NumericNode;
  import com.fasterxml.jackson.databind.node.TextNode;
  import org.apache.camel.CamelContext;
  import org.apache.camel.Converter;
  import org.apache.camel.Exchange;
  import org.apache.camel.component.jackson.JacksonConstants;
  import org.apache.camel.spi.TypeConverterRegistry;
  import org.apache.camel.support.ObjectHelper;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Jackson {@link org.apache.camel.TypeConverter} that allows converting json to/from POJOs and other types. <br/>
   * This implementation uses a fallback converter.
   * <p/>
   * The converter is disabled by default. To enable then set the property {@link JacksonConstants#ENABLE_TYPE_CONVERTER}
   * to <tt>true</tt> on {@link CamelContext#getGlobalOptions()}. <br/>
   * The option {@link JacksonConstants#TYPE_CONVERTER_TO_POJO} can be used to allow converting to POJO types. By default
   * the converter only attempts to convert to primitive types such as String and numbers. To convert to any kind, then
   * enable this by setting {@link JacksonConstants#TYPE_CONVERTER_TO_POJO} to <tt>true</tt> on
   * {@link CamelContext#getGlobalOptions()}.
   */
  @Converter(generateLoader = true)
  public final class JacksonTypeConverters {
      private static final Logger LOG = LoggerFactory.getLogger(JacksonTypeConverters.class);
  
      private final Lock lock;
      private volatile ObjectMapper defaultMapper;
  
      private boolean init;
      private boolean enabled;
      private boolean toPojo;
      private String moduleClassNames;
  
      public JacksonTypeConverters() {
          this.lock = new ReentrantLock();
      }
  
      @Converter
      public JsonNode toJsonNode(String text, Exchange exchange) throws Exception {
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.readTree(text);
      }
  
      @Converter
      public JsonNode toJsonNode(byte[] arr, Exchange exchange) throws Exception {
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.readTree(arr);
      }
  
      @Converter
      public JsonNode toJsonNode(InputStream is, Exchange exchange) throws Exception {
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.readTree(is);
      }
  
      @Converter
      public JsonNode toJsonNode(File file, Exchange exchange) throws Exception {
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.readTree(file);
      }
  
      @Converter
      public JsonNode toJsonNode(Reader reader, Exchange exchange) throws Exception {
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.readTree(reader);
      }
  
      @Converter
      public JsonNode toJsonNode(Map map, Exchange exchange) throws Exception {
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.valueToTree(map);
      }
  
      @Converter
      public String toString(JsonNode node, Exchange exchange) throws Exception {
          if (node instanceof TextNode) {
              TextNode tn = (TextNode) node;
              return tn.textValue();
          }
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          // output as string in pretty mode
          return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(node);
      }
  
      @Converter
      public byte[] toByteArray(JsonNode node, Exchange exchange) throws Exception {
          if (node instanceof TextNode) {
              TextNode tn = (TextNode) node;
              return tn.textValue().getBytes(StandardCharsets.UTF_8);
          }
  
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.writeValueAsBytes(node);
      }
  
      @Converter
      public InputStream toInputStream(JsonNode node, Exchange exchange) throws Exception {
          byte[] arr = toByteArray(node, exchange);
          return new ByteArrayInputStream(arr);
      }
  
      @Converter
      public Map<String, Object> toMap(JsonNode node, Exchange exchange) throws Exception {
          ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
          return mapper.convertValue(node, new TypeReference<>() {
          });
      }
  
      @Converter
      public Reader toReader(JsonNode node, Exchange exchange) throws Exception {
          InputStream is = toInputStream(node, exchange);
          return new InputStreamReader(is);
      }
  
      @Converter
      public Integer toInteger(JsonNode node, Exchange exchange) throws Exception {
          if (node instanceof NumericNode) {
              NumericNode nn = (NumericNode) node;
              if (nn.canConvertToInt()) {
                  return nn.asInt();
              }
          }
          String text = node.asText();
          return Integer.valueOf(text);
      }
  
      @Converter
      public Long toLong(JsonNode node, Exchange exchange) throws Exception {
          if (node instanceof NumericNode) {
              NumericNode nn = (NumericNode) node;
              if (nn.canConvertToLong()) {
                  return nn.asLong();
              }
          }
          String text = node.asText();
          return Long.valueOf(text);
      }
  
      @Converter
      public Boolean toBoolean(BooleanNode node, Exchange exchange) throws Exception {
          return node.asBoolean();
      }
  
      @Converter
      public Boolean toBoolean(JsonNode node, Exchange exchange) throws Exception {
          if (node instanceof BooleanNode) {
              BooleanNode bn = (BooleanNode) node;
              return bn.asBoolean();
          }
          String text = node.asText();
          return org.apache.camel.util.ObjectHelper.toBoolean(text);
      }
  
      @Converter
      public Double toDouble(JsonNode node, Exchange exchange) throws Exception {
          if (node instanceof NumericNode) {
              NumericNode nn = (NumericNode) node;
              if (nn.isFloatingPointNumber()) {
                  return nn.asDouble();
              }
          }
          String text = node.asText();
          return Double.valueOf(text);
      }
  
      @Converter
      public Float toFloat(JsonNode node, Exchange exchange) throws Exception {
          if (node instanceof NumericNode) {
              NumericNode nn = (NumericNode) node;
              if (nn.isFloat()) {
                  return nn.floatValue();
              }
          }
          String text = node.asText();
          return Float.valueOf(text);
      }
  
      @Converter(fallback = true)
      public <T> T convertTo(Class<T> type, Exchange exchange, Object value, TypeConverterRegistry registry) throws Exception {
  
          // only do this if enabled (disabled by default)
          if (!init && exchange != null) {
              initialize(exchange);
          }
  
          if (!enabled) {
              return null;
          }
  
          if (!toPojo && isNotPojoType(type)) {
              return null;
          }
  
          if (exchange != null) {
              ObjectMapper mapper = resolveObjectMapper(exchange.getContext());
  
              // favor use write/read operations as they are higher level than the
              // convertValue
  
              // if we want to convert to a String or byte[] then use write
              // operation
              if (String.class.isAssignableFrom(type)) {
                  String out = mapper.writeValueAsString(value);
                  return type.cast(out);
              } else if (byte[].class.isAssignableFrom(type)) {
                  byte[] out = mapper.writeValueAsBytes(value);
                  return type.cast(out);
              } else if (ByteBuffer.class.isAssignableFrom(type)) {
                  byte[] out = mapper.writeValueAsBytes(value);
                  return type.cast(ByteBuffer.wrap(out));
              } else if (mapper.canSerialize(type) && !Enum.class.isAssignableFrom(type)) {
                  // if the source value type is readable by the mapper then use
                  // its read operation
                  if (String.class.isAssignableFrom(value.getClass())) {
                      return mapper.readValue((String) value, type);
                  } else if (byte[].class.isAssignableFrom(value.getClass())) {
                      return mapper.readValue((byte[]) value, type);
                  } else if (File.class.isAssignableFrom(value.getClass())) {
                      return mapper.readValue((File) value, type);
                  } else if (InputStream.class.isAssignableFrom(value.getClass())) {
                      return mapper.readValue((InputStream) value, type);
                  } else if (Reader.class.isAssignableFrom(value.getClass())) {
                      return mapper.readValue((Reader) value, type);
                  } else {
                      // fallback to generic convert value
                      return mapper.convertValue(value, type);
                  }
              }
          }
  
          // Just return null to let other fallback converter to do the job
          return null;
      }
  
      private void initialize(Exchange exchange) {
          Map<String, String> globalOptions = exchange.getContext().getGlobalOptions();
  
          // init to see if this is enabled
          String text = globalOptions.get(JacksonConstants.ENABLE_TYPE_CONVERTER);
          if (text != null) {
              text = exchange.getContext().resolvePropertyPlaceholders(text);
              enabled = Boolean.parseBoolean(text);
          }
  
          // pojoOnly is disabled by default
          text = globalOptions.get(JacksonConstants.TYPE_CONVERTER_TO_POJO);
          if (text != null) {
              text = exchange.getContext().resolvePropertyPlaceholders(text);
              toPojo = Boolean.parseBoolean(text);
          }
  
          moduleClassNames = globalOptions.get(JacksonConstants.TYPE_CONVERTER_MODULE_CLASS_NAMES);
          init = true;
      }
  
      /**
       * Whether the type is NOT a pojo type but only a set of simple types such as String and numbers.
       */
      private static boolean isNotPojoType(Class<?> type) {
          boolean isString = String.class.isAssignableFrom(type);
          boolean isNumber = Number.class.isAssignableFrom(type) || int.class.isAssignableFrom(type)
                  || long.class.isAssignableFrom(type) || short.class.isAssignableFrom(type)
                  || char.class.isAssignableFrom(type) || float.class.isAssignableFrom(type)
                  || double.class.isAssignableFrom(type);
          return isString || isNumber;
      }
  
      private ObjectMapper resolveObjectMapper(CamelContext camelContext) throws Exception {
          Set<ObjectMapper> mappers = camelContext.getRegistry().findByType(ObjectMapper.class);
          if (mappers.size() == 1) {
              return mappers.iterator().next();
          }
  
          if (defaultMapper == null) {
              lock.lock();
              try {
                  if (defaultMapper == null) {
                      ObjectMapper mapper = new ObjectMapper();
                      if (moduleClassNames != null) {
                          for (Object o : ObjectHelper.createIterable(moduleClassNames)) {
                              Class<Module> type
                                      = camelContext.getClassResolver().resolveMandatoryClass(o.toString(), Module.class);
                              Module module = camelContext.getInjector().newInstance(type);
  
                              LOG.debug("Registering module: {} -> {}", o, module);
                              mapper.registerModule(module);
                          }
                      }
  
                      defaultMapper = mapper;
                  }
              } finally {
                  lock.unlock();
              }
          }
  
          return defaultMapper;
      }
  
  }
  