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// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
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package org.apache.juneau.dto.swagger;

import static org.apache.juneau.internal.BeanPropertyUtils.*;
import static org.apache.juneau.internal.ArrayUtils.*;

import java.util.*;

import org.apache.juneau.*;
import org.apache.juneau.annotation.*;
import org.apache.juneau.internal.*;
import org.apache.juneau.utils.*;

/**
 * Describes a single operation parameter.
 *
 * <p>
 * A unique parameter is defined by a combination of a name and location.
 *
 * <p>
 * There are five possible parameter types.
 * <ul class='spaced-list'>
 *    <li><js>"path"</js> - Used together with Path Templating, where the parameter value is actually part of the
 *       operation's URL.
 *       This does not include the host or base path of the API.
 *       For example, in <code>/items/{itemId}</code>, the path parameter is <code>itemId</code>.
 *    <li><js>"query"</js> - Parameters that are appended to the URL.
 *       For example, in <code>/items?id=###</code>, the query parameter is <code>id</code>.
 *    <li><js>"header"</js> - Custom headers that are expected as part of the request.
 *    <li><js>"body"</js> - The payload that's appended to the HTTP request.
 *       Since there can only be one payload, there can only be one body parameter.
 *       The name of the body parameter has no effect on the parameter itself and is used for documentation purposes
 *       only.
 *       Since Form parameters are also in the payload, body and form parameters cannot exist together for the same
 *       operation.
 *    <li><js>"formData"</js> - Used to describe the payload of an HTTP request when either
 *       <code>application/x-www-form-urlencoded</code>, <code>multipart/form-data</code> or both are used as the
 *       content type of the request (in Swagger's definition, the consumes property of an operation).
 *       This is the only parameter type that can be used to send files, thus supporting the file type.
 *       Since form parameters are sent in the payload, they cannot be declared together with a body parameter for the
 *       same operation.
 *       Form parameters have a different format based on the content-type used (for further details, consult
 *       <code>http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4</code>):
 *       <ul>
 *          <li><js>"application/x-www-form-urlencoded"</js> - Similar to the format of Query parameters but as a
 *             payload.
 *             For example, <code>foo=1&amp;bar=swagger</code> - both <code>foo</code> and <code>bar</code> are form
 *             parameters.
 *             This is normally used for simple parameters that are being transferred.
 *          <li><js>"multipart/form-data"</js> - each parameter takes a section in the payload with an internal header.
 *             For example, for the header <code>Content-Disposition: form-data; name="submit-name"</code> the name of
 *             the parameter is <code>submit-name</code>.
 *             This type of form parameters is more commonly used for file transfers.
 *       </ul>
 *    </li>
 * </ul>
 *
 * <h5 class='section'>Example:</h5>
 * <p class='bcode w800'>
 *    <jc>// Construct using SwaggerBuilder.</jc>
 *    ParameterInfo x = <jsm>parameterInfo</jsm>(<js>"query"</js>, <js>"foo"</js>);
 *
 *    <jc>// Serialize using JsonSerializer.</jc>
 *    String json = JsonSerializer.<jsf>DEFAULT</jsf>.toString(x);
 *
 *    <jc>// Or just use toString() which does the same as above.</jc>
 *    String json = x.toString();
 * </p>
 * <p class='bcode w800'>
 *    <jc>// Output</jc>
 *    {
 *       <js>"in"</js>: <js>"query"</js>,
 *       <js>"name"</js>: <js>"foo"</js>
 *    }
 * </p>
 *
 * <h5 class='section'>See Also:</h5>
 * <ul class='doctree'>
 *    <li class='link'>{@doc juneau-dto.Swagger}
 * </ul>
 */
@Bean(properties="in,name,type,description,required,schema,format,allowEmptyValue,items,collectionFormat,default,maximum,exclusiveMaximum,minimum,exclusiveMinimum,maxLength,minLength,pattern,maxItems,minItems,uniqueItems,enum,multipleOf,x-example,x-examples,*")
public class ParameterInfo extends SwaggerElement {

   private static final String[] VALID_IN = {"query", "header", "path", "formData", "body"};
   private static final String[] VALID_TYPES = {"string", "number", "integer", "boolean", "array", "file"};
   private static final String[] VALID_COLLECTION_FORMATS = {"csv", "ssv", "tsv", "pipes", "multi"};

   private String
      name,
      in,
      description,
      type,
      format,
      pattern,
      collectionFormat;
   private Number
      maximum,
      minimum,
      multipleOf;
   private Integer
      maxLength,
      minLength,
      maxItems,
      minItems;
   private Boolean
      required,
      allowEmptyValue,
      exclusiveMaximum,
      exclusiveMinimum,
      uniqueItems;
   private SchemaInfo schema;
   private Items items;
   private Object _default;
   private List<Object> _enum;
   private String example;
   private Map<String,String> examples;

   /**
    * Default constructor.
    */
   public ParameterInfo() {}

   /**
    * Copy constructor.
    *
    * @param copyFrom The object to copy.
    */
   public ParameterInfo(ParameterInfo copyFrom) {
      super(copyFrom);

      this.name = copyFrom.name;
      this.in = copyFrom.in;
      this.description = copyFrom.description;
      this.type = copyFrom.type;
      this.format = copyFrom.format;
      this.pattern = copyFrom.pattern;
      this.collectionFormat = copyFrom.collectionFormat;
      this.maximum = copyFrom.maximum;
      this.minimum = copyFrom.minimum;
      this.multipleOf = copyFrom.multipleOf;
      this.maxLength = copyFrom.maxLength;
      this.minLength = copyFrom.minLength;
      this.maxItems = copyFrom.maxItems;
      this.minItems = copyFrom.minItems;
      this.required = copyFrom.required;
      this.allowEmptyValue = copyFrom.allowEmptyValue;
      this.exclusiveMaximum = copyFrom.exclusiveMaximum;
      this.exclusiveMinimum = copyFrom.exclusiveMinimum;
      this.uniqueItems = copyFrom.uniqueItems;
      this.schema = copyFrom.schema == null ? null : copyFrom.schema.copy();
      this.items = copyFrom.items == null ? null : copyFrom.items.copy();
      this._default = copyFrom._default;
      this._enum = newList(copyFrom._enum);
      this.example = copyFrom.example;

      if (copyFrom.examples == null)
         this.examples = null;
      else
         this.examples = new LinkedHashMap<>(copyFrom.examples);
   }

   /**
    * Make a deep copy of this object.
    *
    * @return A deep copy of this object.
    */
   public ParameterInfo copy() {
      return new ParameterInfo(this);
   }

   @Override /* SwaggerElement */
   protected ParameterInfo strict() {
      super.strict();
      return this;
   }

   /**
    * Copies any non-null fields from the specified object to this object.
    *
    * @param p
    *    The object to copy fields from.
    *    <br>Can be <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ParameterInfo copyFrom(ParameterInfo p) {
      if (p != null) {
         if (p.name != null)
            name = p.name;
         if (p.in != null)
            in = p.in;
         if (p.description != null)
            description = p.description;
         if (p.type != null)
            type = p.type;
         if (p.format != null)
            format = p.format;
         if (p.pattern != null)
            pattern = p.pattern;
         if (p.collectionFormat != null)
            collectionFormat = p.collectionFormat;
         if (p.maximum != null)
            maximum = p.maximum;
         if (p.minimum != null)
            minimum = p.minimum;
         if (p.multipleOf != null)
            multipleOf = p.multipleOf;
         if (p.maxLength != null)
            maxLength = p.maxLength;
         if (p.minLength != null)
            minLength = p.minLength;
         if (p.maxItems != null)
            maxItems = p.maxItems;
         if (p.minItems != null)
            minItems = p.minItems;
         if (p.required != null)
            required = p.required;
         if (p.allowEmptyValue != null)
            allowEmptyValue = p.allowEmptyValue;
         if (p.exclusiveMaximum != null)
            exclusiveMaximum = p.exclusiveMaximum;
         if (p.exclusiveMinimum != null)
            exclusiveMinimum = p.exclusiveMinimum;
         if (p.uniqueItems != null)
            uniqueItems = p.uniqueItems;
         if (p.schema != null)
            schema = p.schema;
         if (p.items != null)
            items = p.items;
         if (p._default != null)
            _default = p._default;
         if (p._enum != null)
            _enum = p._enum;
         if (p.example != null)
            example = p.example;
         if (p.examples != null)
            examples = p.examples;
      }
      return this;
   }

   /**
    * Bean property getter:  <property>name</property>.
    *
    * <p>
    * The name of the parameter.
    *
    * <h5 class='section'>Notes:</h5>
    * <ul class='spaced-list'>
    *    <li>
    *       Parameter names are case sensitive.
    *    <li>
    *       If <code>in</code> is <js>"path"</js>, the <code>name</code> field MUST correspond to the associated path segment
    *       from the <code>path</code> field in the {@doc SwaggerPathsObject Paths Object}.
    *    <li>
    *       For all other cases, the name corresponds to the parameter name used based on the <code>in</code> property.
    * </ul>
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc SwaggerPathTemplating Path Templating}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getName() {
      return name;
   }

   /**
    * Bean property setter:  <property>name</property>.
    *
    * <p>
    * The name of the parameter.
    *
    * <h5 class='section'>Notes:</h5>
    * <ul class='spaced-list'>
    *    <li>
    *       Parameter names are case sensitive.
    *    <li>
    *       If <code>in</code> is <js>"path"</js>, the <code>name</code> field MUST correspond to the associated path segment
    *       from the <code>path</code> field in the {@doc SwaggerPathsObject Paths Object}.
    *    <li>
    *       For all other cases, the name corresponds to the parameter name used based on the <code>in</code> property.
    * </ul>
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc SwaggerPathTemplating Path Templating}
    * </ul>
    *
    * @param value
    *    The new value for this property.
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ParameterInfo setName(String value) {
      if (! "body".equals(in))
         name = value;
      return this;
   }

   /**
    * Same as {@link #setName(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-String values will be converted to String using <code>toString()</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo name(Object value) {
      return setName(toStringVal(value));
   }

   /**
    * Bean property getter:  <property>in</property>.
    *
    * <p>
    * The location of the parameter.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getIn() {
      return in;
   }

   /**
    * Bean property setter:  <property>in</property>.
    *
    * <p>
    * The location of the parameter.
    *
    * @param value
    *    The new value for this property.
    *    <br>Valid values:
    *    <ul>
    *       <li><js>"query"</js>
    *       <li><js>"header"</js>
    *       <li><js>"path"</js>
    *       <li><js>"formData"</js>
    *       <li><js>"body"</js>
    *    </ul>
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ParameterInfo setIn(String value) {
      if (isStrict() && ! contains(value, VALID_IN))
         throw new FormattedRuntimeException(
            "Invalid value passed in to setIn(String).  Value=''{0}'', valid values={1}",
            value, VALID_IN
         );
      in = value;
      if ("path".equals(value))
         required = true;
      return this;
   }

   /**
    * Same as {@link #setIn(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-String values will be converted to String using <code>toString()</code>.
    *    <br>Valid values:
    *    <ul>
    *       <li><js>"query"</js>
    *       <li><js>"header"</js>
    *       <li><js>"path"</js>
    *       <li><js>"formData"</js>
    *       <li><js>"body"</js>
    *    </ul>
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ParameterInfo in(Object value) {
      return setIn(toStringVal(value));
   }

   /**
    * Bean property getter:  <property>description</property>.
    *
    * <p>
    * A brief description of the parameter.
    * <br>This could contain examples of use.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getDescription() {
      return description;
   }

   /**
    * Bean property setter:  <property>description</property>.
    *
    * <p>
    * A brief description of the parameter.
    * <br>This could contain examples of use.
    *
    * @param value
    *    The new value for this property.
    *    <br>{@doc GFM} can be used for rich text representation.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setDescription(String value) {
      description = value;
      return this;
   }

   /**
    * Same as {@link #setDescription(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>{@doc GFM} can be used for rich text representation.
    *    <br>Non-String values will be converted to String using <code>toString()</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo description(Object value) {
      return setDescription(toStringVal(value));
   }

   /**
    * Bean property getter:  <property>required</property>.
    *
    * <p>
    * Determines whether this parameter is mandatory.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Boolean getRequired() {
      return required;
   }

   /**
    * Bean property setter:  <property>required</property>.
    *
    * <p>
    * Determines whether this parameter is mandatory.
    *
    * <p>
    *
    * @param value
    *    The new value for this property.
    *    <br>If the parameter is <code>in</code> <js>"path"</js>, this property is required and its value MUST be <jk>true</jk>.
    *    <br>Otherwise, the property MAY be included and its default value is <jk>false</jk>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setRequired(Boolean value) {
      required = value;
      return this;
   }

   /**
    * Same as {@link #setRequired(Boolean)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-boolean values will be converted to boolean using <code>Boolean.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>If the parameter is <code>in</code> <js>"path"</js>, this property is required and its value MUST be <jk>true</jk>.
    *    <br>Otherwise, the property MAY be included and its default value is <jk>false</jk>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo required(Object value) {
      return setRequired(toBoolean(value));
   }

   /**
    * Bean property getter:  <property>schema</property>.
    *
    * <p>
    * The schema defining the type used for the body parameter.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public SchemaInfo getSchema() {
      return schema;
   }

   /**
    * Bean property setter:  <property>schema</property>.
    *
    * <p>
    * The schema defining the type used for the body parameter.
    *
    * @param value
    *    The new value for this property.
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ParameterInfo setSchema(SchemaInfo value) {
      schema = value;
      return this;
   }

   /**
    * Same as {@link #setSchema(SchemaInfo)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Valid types:
    *    <ul>
    *       <li>{@link SchemaInfo}
    *       <li><code>String</code> - JSON object representation of {@link SchemaInfo}
    *          <h5 class='figure'>Example:</h5>
    *          <p class='bcode w800'>
    *    schema(<js>"{type:'type',description:'description',...}"</js>);
    *          </p>
    *    </ul>
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ParameterInfo schema(Object value) {
      return setSchema(toType(value, SchemaInfo.class));
   }

   /**
    * Bean property getter:  <property>type</property>.
    *
    * <p>
    * The type of the parameter.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getType() {
      return type;
   }

   /**
    * Bean property setter:  <property>type</property>.
    *
    * <p>
    * The type of the parameter.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul class='doctree'>
    *    <li class='extlink'>{@doc SwaggerDataTypes}
    * </ul>
    *
    * @param value
    *    The new value for this property.
    *    <br>Valid values:
    *    <ul>
    *       <li><js>"string"</js>
    *       <li><js>"number"</js>
    *       <li><js>"integer"</js>
    *       <li><js>"boolean"</js>
    *       <li><js>"array"</js>
    *       <li><js>"file"</js>
    *    </ul>
    *    <br>If type is <js>"file"</js>, the <code>consumes</code> MUST be either <js>"multipart/form-data"</js>, <js>"application/x-www-form-urlencoded"</js>
    *       or both and the parameter MUST be <code>in</code> <js>"formData"</js>.
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ParameterInfo setType(String value) {
      if (isStrict() && ! contains(value, VALID_TYPES))
         throw new FormattedRuntimeException(
            "Invalid value passed in to setType(String).  Value=''{0}'', valid values={1}",
            value, VALID_TYPES
         );
      type = value;
      return this;
   }

   /**
    * Same as {@link #setType(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-String values will be converted to String using <code>toString()</code>.
    *    <br>Valid values:
    *    <ul>
    *       <li><js>"string"</js>
    *       <li><js>"number"</js>
    *       <li><js>"integer"</js>
    *       <li><js>"boolean"</js>
    *       <li><js>"array"</js>
    *       <li><js>"file"</js>
    *    </ul>
    *    <br>If type is <js>"file"</js>, the <code>consumes</code> MUST be either <js>"multipart/form-data"</js>, <js>"application/x-www-form-urlencoded"</js>
    *       or both and the parameter MUST be <code>in</code> <js>"formData"</js>.
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ParameterInfo type(Object value) {
      return setType(toStringVal(value));
   }

   /**
    * Bean property getter:  <property>format</property>.
    *
    * <p>
    * The extending format for the previously mentioned type.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc SwaggerDataTypeFormats}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getFormat() {
      return format;
   }

   /**
    * Bean property setter:  <property>format</property>.
    *
    * <p>
    * The extending format for the previously mentioned type.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul class='doctree'>
    *    <li class='extlink'>{@doc SwaggerDataTypes}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setFormat(String value) {
      format = value;
      return this;
   }

   /**
    * Same as {@link #setFormat(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-String values will be converted to String using <code>toString()</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo format(Object value) {
      return setFormat(toStringVal(value));
   }

   /**
    * Bean property getter:  <property>allowEmptyValue</property>.
    *
    * <p>
    * Sets the ability to pass empty-valued parameters.
    *
    * <p>
    * This is valid only for either <code>query</code> or <code>formData</code> parameters and allows you to send a
    * parameter with a name only or an empty value.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Boolean getAllowEmptyValue() {
      return allowEmptyValue;
   }

   /**
    * Bean property setter:  <property>allowEmptyValue</property>.
    *
    * <p>
    * Sets the ability to pass empty-valued parameters.
    *
    * <p>
    * This is valid only for either <code>query</code> or <code>formData</code> parameters and allows you to send a
    * parameter with a name only or an empty value.
    *
    * @param value
    *    The new value for this property.
    *    <br>Can be <jk>null</jk> to unset the property.
    *    <br>Default is <jk>false</jk>.
    * @return This object (for method chaining).
    */
   public ParameterInfo setAllowEmptyValue(Boolean value) {
      allowEmptyValue = value;
      return this;
   }

   /**
    * Same as {@link #setAllowEmptyValue(Boolean)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-boolean values will be converted to boolean using <code>Boolean.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    *    <br>Default is <jk>false</jk>.
    * @return This object (for method chaining).
    */
   public ParameterInfo allowEmptyValue(Object value) {
      return setAllowEmptyValue(toBoolean(value));
   }

   /**
    * Bean property getter:  <property>items</property>.
    *
    * <p>
    * Describes the type of items in the array.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Items getItems() {
      return items;
   }

   /**
    * Bean property setter:  <property>items</property>.
    *
    * <p>
    * Describes the type of items in the array.
    *
    * @param value
    *    The new value for this property.
    *    <br>Property value is required if <code>type</code> is <js>"array"</js>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setItems(Items value) {
      items = value;
      return this;
   }

   /**
    * Same as {@link #setItems(Items)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Property value is required if <code>type</code> is <js>"array"</js>.
    *    <br>Valid types:
    *    <ul>
    *       <li>{@link Items}
    *       <li><code>String</code> - JSON object representation of {@link Items}
    *          <h5 class='figure'>Example:</h5>
    *          <p class='bcode w800'>
    *    items(<js>"{type:'type',format:'format',...}"</js>);
    *          </p>
    *    </ul>
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo items(Object value) {
      return setItems(toType(value, Items.class));
   }

   /**
    * Bean property getter:  <property>collectionFormat</property>.
    *
    * <p>
    * Determines the format of the array if type array is used.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getCollectionFormat() {
      return collectionFormat;
   }

   /**
    * Bean property setter:  <property>collectionFormat</property>.
    *
    * <p>
    * Determines the format of the array if type array is used.
    *
    * @param value
    *    The new value for this property.
    *    <br>Valid values:
    *    <ul>
    *       <li><js>"csv"</js> (default) - comma separated values <code>foo,bar</code>.
    *       <li><js>"ssv"</js> - space separated values <code>foo bar</code>.
    *       <li><js>"tsv"</js> - tab separated values <code>foo\tbar</code>.
    *       <li><js>"pipes"</js> - pipe separated values <code>foo|bar</code>.
    *       <li><js>"multi"</js> - corresponds to multiple parameter instances instead of multiple values for a single
    *          instance <code>foo=bar&amp;foo=baz</code>.
    *          <br>This is valid only for parameters <code>in</code> <js>"query"</js> or <js>"formData"</js>.
    *    </ul>
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setCollectionFormat(String value) {
      if (isStrict() && ! contains(value, VALID_COLLECTION_FORMATS))
         throw new FormattedRuntimeException(
            "Invalid value passed in to setCollectionFormat(String).  Value=''{0}'', valid values={1}",
            value, VALID_COLLECTION_FORMATS
         );
      collectionFormat = value;
      return this;
   }

   /**
    * Same as {@link #setCollectionFormat(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-String values will be converted to String using <code>toString()</code>.
    *    <br>Valid values:
    *    <ul>
    *       <li><js>"csv"</js> (default) - comma separated values <code>foo,bar</code>.
    *       <li><js>"ssv"</js> - space separated values <code>foo bar</code>.
    *       <li><js>"tsv"</js> - tab separated values <code>foo\tbar</code>.
    *       <li><js>"pipes"</js> - pipe separated values <code>foo|bar</code>.
    *       <li><js>"multi"</js> - corresponds to multiple parameter instances instead of multiple values for a single
    *          instance <code>foo=bar&amp;foo=baz</code>.
    *          <br>This is valid only for parameters <code>in</code> <js>"query"</js> or <js>"formData"</js>.
    *    </ul>
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo collectionFormat(Object value) {
      return setCollectionFormat(toStringVal(value));
   }

   /**
    * Bean property getter:  <property>default</property>.
    *
    * <p>
    * Declares the value of the parameter that the server will use if none is provided, for example a <js>"count"</js>
    * to control the number of results per page might default to 100 if not supplied by the client in the request.
    *
    * (Note: <js>"default"</js> has no meaning for required parameters.)
    * Unlike JSON Schema this value MUST conform to the defined <code>type</code> for this parameter.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Object getDefault() {
      return _default;
   }

   /**
    * Bean property setter:  <property>default</property>.
    *
    * <p>
    * Declares the value of the parameter that the server will use if none is provided, for example a <js>"count"</js>
    * to control the number of results per page might default to 100 if not supplied by the client in the request.
    * (Note: <js>"default"</js> has no meaning for required parameters.)
    * Unlike JSON Schema this value MUST conform to the defined <code>type</code> for this parameter.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setDefault(Object value) {
      _default = value;
      return this;
   }

   /**
    * Same as {@link #setDefault(Object)}.
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo _default(Object value) {
      return setDefault(value);
   }

   /**
    * Bean property getter:  <property>maximum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Number getMaximum() {
      return maximum;
   }

   /**
    * Bean property setter:  <property>maximum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setMaximum(Number value) {
      maximum = value;
      return this;
   }

   /**
    * Same as {@link #setMaximum(Number)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-Number values will be converted to Number using <code>toString()</code> then best number match.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo maximum(Object value) {
      return setMaximum(toNumber(value));
   }

   /**
    * Bean property getter:  <property>exclusiveMaximum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Boolean getExclusiveMaximum() {
      return exclusiveMaximum;
   }

   /**
    * Bean property setter:  <property>exclusiveMaximum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setExclusiveMaximum(Boolean value) {
      exclusiveMaximum = value;
      return this;
   }

   /**
    * Same as {@link #setExclusiveMaximum(Boolean)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-boolean values will be converted to boolean using <code>Boolean.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo exclusiveMaximum(Object value) {
      return setExclusiveMaximum(toBoolean(value));
   }

   /**
    * Bean property getter:  <property>minimum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Number getMinimum() {
      return minimum;
   }

   /**
    * Bean property setter:  <property>minimum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setMinimum(Number value) {
      minimum = value;
      return this;
   }

   /**
    * Same as {@link #setMinimum(Number)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-Number values will be converted to Number using <code>toString()</code> then best number match.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo minimum(Object value) {
      return setMinimum(toNumber(value));
   }

   /**
    * Bean property getter:  <property>exclusiveMinimum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Boolean getExclusiveMinimum() {
      return exclusiveMinimum;
   }

   /**
    * Bean property setter:  <property>exclusiveMinimum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setExclusiveMinimum(Boolean value) {
      exclusiveMinimum = value;
      return this;
   }

   /**
    * Same as {@link #setExclusiveMinimum(Boolean)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-boolean values will be converted to boolean using <code>Boolean.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo exclusiveMinimum(Object value) {
      return setExclusiveMinimum(toBoolean(value));
   }

   /**
    * Bean property getter:  <property>maxLength</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Integer getMaxLength() {
      return maxLength;
   }

   /**
    * Bean property setter:  <property>maxLength</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setMaxLength(Integer value) {
      maxLength = value;
      return this;
   }

   /**
    * Same as {@link #setMaxLength(Integer)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-Integer values will be converted to Integer using <code>Integer.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo maxLength(Object value) {
      return setMaxLength(toInteger(value));
   }

   /**
    * Bean property getter:  <property>minLength</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Integer getMinLength() {
      return minLength;
   }

   /**
    * Bean property setter:  <property>minLength</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setMinLength(Integer value) {
      minLength = value;
      return this;
   }

   /**
    * Same as {@link #setMinLength(Integer)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-Integer values will be converted to Integer using <code>Integer.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo minLength(Object value) {
      return setMinLength(toInteger(value));
   }

   /**
    * Bean property getter:  <property>pattern</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getPattern() {
      return pattern;
   }

   /**
    * Bean property setter:  <property>pattern</property>.
    *
    * <p>
    * This string SHOULD be a valid regular expression.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setPattern(String value) {
      pattern = value;
      return this;
   }

   /**
    * Same as {@link #setPattern(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-String values will be converted to String using <code>toString()</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo pattern(Object value) {
      return setPattern(toStringVal(value));
   }

   /**
    * Bean property getter:  <property>maxItems</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Integer getMaxItems() {
      return maxItems;
   }

   /**
    * Bean property setter:  <property>maxItems</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setMaxItems(Integer value) {
      maxItems = value;
      return this;
   }

   /**
    * Same as {@link #setMaxItems(Integer)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-Integer values will be converted to Integer using <code>Integer.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo maxItems(Object value) {
      return setMaxItems(toInteger(value));
   }

   /**
    * Bean property getter:  <property>minItems</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Integer getMinItems() {
      return minItems;
   }

   /**
    * Bean property setter:  <property>minItems</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setMinItems(Integer value) {
      minItems = value;
      return this;
   }

   /**
    * Same as {@link #setMinItems(Integer)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-Integer values will be converted to Integer using <code>Integer.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo minItems(Object value) {
      return setMinItems(toInteger(value));
   }

   /**
    * Bean property getter:  <property>uniqueItems</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Boolean getUniqueItems() {
      return uniqueItems;
   }

   /**
    * Bean property setter:  <property>uniqueItems</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value The new value for this property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setUniqueItems(Boolean value) {
      uniqueItems = value;
      return this;
   }

   /**
    * Same as {@link #setUniqueItems(Boolean)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-boolean values will be converted to boolean using <code>Boolean.<jsm>valueOf</jsm>(value.toString())</code>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo uniqueItems(Object value) {
      return setUniqueItems(toBoolean(value));
   }

   /**
    * Bean property getter:  <property>enum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public List<Object> getEnum() {
      return _enum;
   }

   /**
    * Bean property setter:  <property>enum</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value
    *    The new value for this property.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setEnum(Collection<Object> value) {
      _enum = newList(value);
      return this;
   }

   /**
    * Adds one or more values to the <property>enum</property> property.
    *
    * @param value
    *    The values to add to this property.
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ParameterInfo addEnum(Collection<Object> value) {
      _enum = addToList(_enum, value);
      return this;
   }

   /**
    * Adds one or more values to the <property>enum</property> property.
    *
    * @param values
    *    The values to add to this property.
    *    <br>Valid types:
    *    <ul>
    *       <li><code>Object</code>
    *       <li><code>Collection&lt;Object&gt;</code>
    *       <li><code>String</code> - JSON array representation of <code>Collection&lt;Object&gt;</code>
    *          <h5 class='figure'>Example:</h5>
    *          <p class='bcode w800'>
    *    _enum(<js>"['foo','bar']"</js>);
    *          </p>
    *       <li><code>String</code> - Individual values
    *          <h5 class='figure'>Example:</h5>
    *          <p class='bcode w800'>
    *    _enum(<js>"foo"</js>, <js>"bar"</js>);
    *          </p>
    *    </ul>
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ParameterInfo _enum(Object...values) {
      _enum = addToList(_enum, values, Object.class);
      return this;
   }

   /**
    * Bean property getter:  <property>multipleOf</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Number getMultipleOf() {
      return multipleOf;
   }

   /**
    * Bean property setter:  <property>multipleOf</property>.
    *
    * <h5 class='section'>See Also:</h5>
    * <ul>
    *    <li class='extlink'>{@doc JsonSchemaValidation}
    * </ul>
    *
    * @param value
    *    The new value for this property.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo setMultipleOf(Number value) {
      multipleOf = value;
      return this;
   }

   /**
    * Same as {@link #setMultipleOf(Number)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-Number values will be converted to Number using <code>toString()</code> then best number match.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ParameterInfo multipleOf(Object value) {
      return setMultipleOf(toNumber(value));
   }

   /**
    * Bean property getter:  <property>x-example</property>.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   @BeanProperty("x-example")
   public String getExample() {
      return example;
   }

   /**
    * Bean property setter:  <property>x-example</property>.
    *
    * @param value
    *    The new value for this property.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   @BeanProperty("x-example")
   public ParameterInfo setExample(String value) {
      example = value;
      return this;
   }

   /**
    * Bean property setter:  <property>x-example</property>.
    *
    * @param value The property value.
    * @return This object (for method chaining).
    */
   public ParameterInfo example(Object value) {
      example = StringUtils.asString(value);
      return this;
   }

   /**
    * Bean property getter:  <property>x-examples</property>.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   @BeanProperty("x-examples")
   public Map<String,String> getExamples() {
      return examples;
   }

   /**
    * Bean property setter:  <property>x-examples</property>.
    *
    * @param value
    *    The new value for this property.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   @BeanProperty("x-examples")
   public ParameterInfo setExamples(Map<String,String> value) {
      examples = newMap(value);
      return this;
   }

   /**
    * Adds one or more values to the <property>x-examples</property> property.
    *
    * @param values
    *    The values to add to this property.
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ParameterInfo addExamples(Map<String,String> values) {
      examples = addToMap(examples, values);
      return this;
   }

   /**
    * Adds a single value to the <property>x-examples</property> property.
    *
    * @param name The extra property name.
    * @param value The extra property value.
    * @return This object (for method chaining).
    */
   public ParameterInfo example(String name, String value) {
      examples = addToMap(examples, name, value);
      return this;
   }

   /**
    * Adds one or more values to the <property>x-examples</property> property.
    *
    * @param values
    *    The values to add to this property.
    *    <br>Valid types:
    *    <ul>
    *       <li><code>Map&lt;String,String&gt;</code>
    *       <li><code>String</code> - JSON object representation of <code>Map&lt;String,Object&gt;</code>
    *          <h5 class='figure'>Example:</h5>
    *          <p class='bcode w800'>
    *    examples(<js>"{'text/json':'{foo:\\'bar\\'}'}"</js>);
    *          </p>
    *    </ul>
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ParameterInfo examples(Object...values) {
      examples = addToMap(examples, values, String.class, String.class);
      return this;
   }

   @Override /* SwaggerElement */
   public <T> T get(String property, Class<T> type) {
      if (property == null)
         return null;
      switch (property) {
         case "name": return toType(getName(), type);
         case "in": return toType(getIn(), type);
         case "description": return toType(getDescription(), type);
         case "required": return toType(getRequired(), type);
         case "schema": return toType(getSchema(), type);
         case "type": return toType(getType(), type);
         case "format": return toType(getFormat(), type);
         case "allowEmptyValue": return toType(getAllowEmptyValue(), type);
         case "items": return toType(getItems(), type);
         case "collectionFormat": return toType(getCollectionFormat(), type);
         case "default": return toType(getDefault(), type);
         case "maximum": return toType(getMaximum(), type);
         case "exclusiveMaximum": return toType(getExclusiveMaximum(), type);
         case "minimum": return toType(getMinimum(), type);
         case "exclusiveMinimum": return toType(getExclusiveMinimum(), type);
         case "maxLength": return toType(getMaxLength(), type);
         case "minLength": return toType(getMinLength(), type);
         case "pattern": return toType(getPattern(), type);
         case "maxItems": return toType(getMaxItems(), type);
         case "minItems": return toType(getMinItems(), type);
         case "uniqueItems": return toType(getUniqueItems(), type);
         case "enum": return toType(getEnum(), type);
         case "multipleOf": return toType(getMultipleOf(), type);
         case "x-example": return toType(getExample(), type);
         case "x-examples": return toType(getExamples(), type);
         default: return super.get(property, type);
      }
   }

   @Override /* SwaggerElement */
   public ParameterInfo set(String property, Object value) {
      if (property == null)
         return this;
      switch (property) {
         case "name": return name(value);
         case "in": return in(value);
         case "description": return description(value);
         case "required": return required(value);
         case "schema": return schema(value);
         case "type": return type(value);
         case "format": return format(value);
         case "allowEmptyValue": return allowEmptyValue(value);
         case "items": return items(value);
         case "collectionFormat": return collectionFormat(value);
         case "default": return _default(value);
         case "maximum": return maximum(value);
         case "exclusiveMaximum": return exclusiveMaximum(value);
         case "minimum": return minimum(value);
         case "exclusiveMinimum": return exclusiveMinimum(value);
         case "maxLength": return maxLength(value);
         case "minLength": return minLength(value);
         case "pattern": return pattern(value);
         case "maxItems": return maxItems(value);
         case "minItems": return minItems(value);
         case "uniqueItems": return uniqueItems(value);
         case "enum": return setEnum(null)._enum(value);
         case "multipleOf": return multipleOf(value);
         case "x-example": return example(value);
         case "x-examples": return examples(value);
         default:
            super.set(property, value);
            return this;
      }
   }

   @Override /* SwaggerElement */
   public Set<String> keySet() {
      ASet<String> s = new ASet<String>()
         .appendIf(name != null, "name")
         .appendIf(in != null, "in")
         .appendIf(description != null, "description")
         .appendIf(required != null, "required")
         .appendIf(schema != null, "schema")
         .appendIf(type != null, "type")
         .appendIf(format != null, "format")
         .appendIf(allowEmptyValue != null, "allowEmptyValue")
         .appendIf(items != null, "items")
         .appendIf(collectionFormat != null, "collectionFormat")
         .appendIf(_default != null, "default")
         .appendIf(maximum != null, "maximum")
         .appendIf(exclusiveMaximum != null, "exclusiveMaximum")
         .appendIf(minimum != null, "minimum")
         .appendIf(exclusiveMinimum != null, "exclusiveMinimum")
         .appendIf(maxLength != null, "maxLength")
         .appendIf(minLength != null, "minLength")
         .appendIf(pattern != null, "pattern")
         .appendIf(maxItems != null, "maxItems")
         .appendIf(minItems != null, "minItems")
         .appendIf(uniqueItems != null, "uniqueItems")
         .appendIf(_enum != null, "enum")
         .appendIf(multipleOf != null, "multipleOf")
         .appendIf(example != null, "x-example")
         .appendIf(examples != null, "x-examples");
      return new MultiSet<>(s, super.keySet());
   }

   /**
    * Resolves any <js>"$ref"</js> attributes in this element.
    *
    * @param swagger The swagger document containing the definitions.
    * @param refStack Keeps track of previously-visited references so that we don't cause recursive loops.
    * @param maxDepth
    *    The maximum depth to resolve references.
    *    <br>After that level is reached, <code>$ref</code> references will be left alone.
    *    <br>Useful if you have very complex models and you don't want your swagger page to be overly-complex.
    * @return
    *    This object with references resolved.
    *    <br>May or may not be the same object.
    */
   public ParameterInfo resolveRefs(Swagger swagger, Deque<String> refStack, int maxDepth) {

      if (schema != null)
         schema = schema.resolveRefs(swagger, refStack, maxDepth);

      if (items != null)
         items = items.resolveRefs(swagger, refStack, maxDepth);

      return this;
   }
}