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

import java.io.*;
import java.lang.reflect.*;
import java.util.*;

import org.apache.juneau.json.*;
import org.apache.juneau.parser.*;
import org.apache.juneau.serializer.*;
import org.apache.juneau.utils.*;

/**
 * Java implementation of a JSON array.
 * 
 * <p>
 * An extension of {@link LinkedList}, so all methods available to in that class are also available to this class.
 * 
 * <p>
 * Note that the use of this class is optional.
 * The serializers will accept any objects that implement the {@link Collection} interface.
 * But this class provides some useful additional functionality when working with JSON models constructed from Java
 * Collections Framework objects.
 * For example, a constructor is provided for converting a JSON array string directly into a {@link List}.
 * It also contains accessor methods for to avoid common typecasting when accessing elements in a list.
 * 
 * <h5 class='section'>Example:</h5>
 * <p class='bcode'>
 *    <jc>// Construct an empty List</jc>
 *    List l = <jk>new</jk> ObjectList();
 * 
 *    <jc>// Construct a list of objects using various methods</jc>
 *    l = <jk>new</jk> ObjectList().append(<js>"foo"</js>).append(123).append(<jk>true</jk>);
 *    l = <jk>new</jk> ObjectList().append(<js>"foo"</js>, 123, <jk>true</jk>);  <jc>// Equivalent</jc>
 *    l = <jk>new</jk> ObjectList(<js>"foo"</js>, 123, <jk>true</jk>);  <jc>// Equivalent</jc>
 * 
 *    <jc>// Construct a list of integers from JSON</jc>
 *    l = <jk>new</jk> ObjectList(<js>"[1,2,3]"</js>);
 * 
 *    <jc>// Construct a list of generic ObjectMap objects from JSON</jc>
 *    l = <jk>new</jk> ObjectList(<js>"[{foo:'bar'},{baz:'bing'}]"</js>);
 * 
 *    <jc>// Construct a list of integers from XML</jc>
 *    String xml = <js>"&lt;array&gt;&lt;number&gt;1&lt;/number&gt;&lt;number&gt;2&lt;/number&gt;&lt;number&gt;3&lt;/number&gt;&lt;/array&gt;"</js>;
 *    l = <jk>new</jk> ObjectList(xml, DataFormat.<jsf>XML</jsf>);
 *    l = (List)XmlParser.<jsf>DEFAULT</jsf>.parse(xml);  <jc>// Equivalent</jc>
 *    l = (List)XmlParser.<jsf>DEFAULT</jsf>.parse(Object.<jk>class</jk>, xml);  <jc>// Equivalent</jc>
 *    l = XmlParser.<jsf>DEFAULT</jsf>.parse(List.<jk>class</jk>, xml);  <jc>// Equivalent</jc>
 *    l = XmlParser.<jsf>DEFAULT</jsf>.parse(ObjectList.<jk>class</jk>, xml);  <jc>// Equivalent</jc>
 * 
 *    <jc>// Construct JSON from ObjectList</jc>
 *    l = <jk>new</jk> ObjectList(<js>"[{foo:'bar'},{baz:'bing'}]"</js>);
 *    String json = l.toString();  <jc>// Produces "[{foo:'bar'},{baz:'bing'}]"</jc>
 *    json = l.toString(JsonSerializer.<jsf>DEFAULT_CONDENSED</jsf>);  <jc>// Equivalent</jc>
 *    json = JsonSerializer.<jsf>DEFAULT_CONDENSED</jsf>.serialize(l);  <jc>// Equivalent</jc>
 * 
 *    <jc>// Get one of the entries in the list as an Integer</jc>
 *    l = <jk>new</jk> ObjectList(<js>"[1,2,3]"</js>);
 *    Integer i = l.getInt(1);
 *    i = l.get(Integer.<jk>class</jk>, 1);  <jc>// Equivalent</jc>
 * 
 *    <jc>// Get one of the entries in the list as an Float</jc>
 *    l = <jk>new</jk> ObjectList(<js>"[1,2,3]"</js>);
 *    Float f = l.getFloat(1); <jc>// Returns 2f </jc>
 *    f = l.get(Float.<jk>class</jk>, 1);  <jc>// Equivalent</jc>
 * 
 *    <jc>// Same as above, except converted to a String</jc>
 *    l = <jk>new</jk> ObjectList(<js>"[1,2,3]"</js>);
 *    String s = l.getString(1); <jc>// Returns "2" </jc>
 *    s = l.get(String.<jk>class</jk>, 1);  <jc>// Equivalent</jc>
 * 
 *    <jc>// Get one of the entries in the list as a bean (converted to a bean if it isn't already one)</jc>
 *    l = <jk>new</jk> ObjectList(<js>"[{name:'John Smith',age:45}]"</js>);
 *    Person p = l.get(Person.<jk>class</jk>, 0);
 * 
 *    <jc>// Iterate over a list of beans using the elements() method</jc>
 *    ObjectList ObjectList = <jk>new</jk> ObjectList(<js>"[{name:'John Smith',age:45}]"</js>);
 *    <jk>for</jk> (Person p : ObjectList.elements(Person.<jk>class</jk>) {
 *       <jc>// Do something with p</jc>
 *    }
 * </p>
 * 
 * <p>
 * This class is not thread safe.
 */
public class ObjectList extends LinkedList<Object> {
   private static final long serialVersionUID = 1L;

   transient BeanSession session = null;
   private transient PojoRest pojoRest;

   /**
    * An empty read-only ObjectList.
    */
   public static final ObjectList EMPTY_LIST = new ObjectList() {
      private static final long serialVersionUID = 1L;

      @Override /* List */
      public void add(int location, Object object) {
         throw new UnsupportedOperationException();
      }

      @Override /* List */
      public ListIterator<Object> listIterator(final int location) {
         return Collections.emptyList().listIterator(location);
      }

      @Override /* List */
      public Object remove(int location) {
         throw new UnsupportedOperationException();
      }

      @Override /* List */
      public Object set(int location, Object object) {
         throw new UnsupportedOperationException();
      }

      @Override /* List */
      public List<Object> subList(int start, int end) {
         return Collections.emptyList().subList(start, end);
      }
   };

   /**
    * Construct a JSON array directly from text using the specified parser.
    * 
    * @param s The string being parsed.
    * @param p The parser to use to parse the input.
    * @throws ParseException If the input contains a syntax error or is malformed.
    */
   public ObjectList(CharSequence s, Parser p) throws ParseException {
      this(p == null ? BeanContext.DEFAULT.createSession() : p.createBeanSession());
      if (p == null)
         p = JsonParser.DEFAULT;
      try {
         if (s != null)
            p.parseIntoCollection(s, this, session.object());
      } catch (ParseException e) {
         throw new ParseException("Invalid input for {0} parser.\n---start---\n{1}\n---end---",
            p.getClass().getSimpleName(), s).initCause(e);
      }
   }

   /**
    * Shortcut for <code><jk>new</jk> ObjectList(String,JsonParser.<jsf>DEFAULT</jsf>);</code>
    * 
    * @param s The string being parsed.
    * @throws ParseException If the input contains a syntax error or is malformed.
    */
   public ObjectList(CharSequence s) throws ParseException {
      this(s, null);
   }

   /**
    * Construct a JSON array directly from a reader using the specified parser.
    * 
    * @param r
    *    The reader to read from.
    *    Will automatically be wrapped in a {@link BufferedReader} if it isn't already a BufferedReader.
    * @param p The parser to use to parse the input.
    * @throws ParseException If the input contains a syntax error or is malformed.
    * @throws IOException If a problem occurred trying to read from the reader.
    */
   public ObjectList(Reader r, Parser p) throws ParseException, IOException {
      this(p == null ? BeanContext.DEFAULT.createSession() : p.createBeanSession());
      parseReader(r, p);
   }

   /**
    * Shortcut for <code><jk>new</jk> ObjectList(reader, JsonParser.<jsf>DEFAULT</jsf>)</code>.
    * 
    * @param r
    *    The reader to read from.
    *    The reader will be wrapped in a {@link BufferedReader} if it isn't already.
    * @throws ParseException If the input contains a syntax error or is malformed.
    * @throws IOException If a problem occurred trying to read from the reader.
    */
   public ObjectList(Reader r) throws ParseException, IOException {
      this(BeanContext.DEFAULT.createSession());
      parseReader(r, JsonParser.DEFAULT);
   }

   private void parseReader(Reader r, Parser p) throws ParseException {
      if (p == null)
         p = JsonParser.DEFAULT;
      p.parseIntoCollection(r, this, session.object());
   }

   /**
    * Construct an empty JSON array. (i.e. an empty {@link LinkedList}).
    */
   public ObjectList() {
      this(BeanContext.DEFAULT.createSession());
   }

   /**
    * Construct an empty JSON array with the specified bean context. (i.e. an empty {@link LinkedList}).
    * 
    * @param session The bean context to associate with this object list for creating beans.
    */
   public ObjectList(BeanSession session) {
      super();
      this.session = session;
   }

   /**
    * Construct a JSON array and fill it with the specified objects.
    * 
    * @param o A list of objects to add to this list.
    */
   public ObjectList(Object... o) {
      super(Arrays.asList(o));
   }

   /**
    * Construct a JSON array and fill it with the specified collection of objects.
    * 
    * @param c A list of objects to add to this list.
    */
   public ObjectList(Collection<?> c) {
      super(c);
   }

   /**
    * Override the default bean session used for converting POJOs.
    * 
    * <p>
    * Default is {@link BeanContext#DEFAULT}, which is sufficient in most cases.
    * 
    * <p>
    * Useful if you're serializing/parsing beans with transforms defined.
    * 
    * @param session The new bean session.
    * @return This object (for method chaining).
    */
   public ObjectList setBeanSession(BeanSession session) {
      this.session = session;
      return this;
   }

   /**
    * Convenience method for adding multiple objects to this list.
    * 
    * @param o The objects to add to the list.
    * @return This object (for method chaining).
    */
   public ObjectList append(Object...o) {
      for (Object o2 : o)
         add(o2);
      return this;
   }

   /**
    * Get the entry at the specified index, converted to the specified type.
    * 
    * <p>
    * This is the preferred get method for simple types.
    * 
    * <h5 class='section'>Examples:</h5>
    * <p class='bcode'>
    *    ObjectList l = <jk>new</jk> ObjectList(<js>"..."</js>);
    * 
    *    <jc>// Value converted to a string.</jc>
    *    String s = l.get(1, String.<jk>class</jk>);
    * 
    *    <jc>// Value converted to a bean.</jc>
    *    MyBean b = l.get(2, MyBean.<jk>class</jk>);
    * 
    *    <jc>// Value converted to a bean array.</jc>
    *    MyBean[] ba = l.get(3, MyBean[].<jk>class</jk>);
    * 
    *    <jc>// Value converted to a linked-list of objects.</jc>
    *    List l1 = l.get(4, LinkedList.<jk>class</jk>);
    * 
    *    <jc>// Value converted to a map of object keys/values.</jc>
    *    Map m1 = l.get(5, TreeMap.<jk>class</jk>);
    * </p>
    * 
    * <p>
    * See {@link BeanSession#convertToType(Object, ClassMeta)} for the list of valid data conversions.
    * 
    * @param index The index into this list.
    * @param type The type of object to convert the entry to.
    * @param <T> The type of object to convert the entry to.
    * @return The converted entry.
    */
   public <T> T get(int index, Class<T> type) {
      return session.convertToType(get(index), type);
   }

   /**
    * Get the entry at the specified index, converted to the specified type.
    * 
    * <p>
    * The type can be a simple type (e.g. beans, strings, numbers) or parameterized type (collections/maps).
    * 
    * <h5 class='section'>Examples:</h5>
    * <p class='bcode'>
    *    ObjectList l = <jk>new</jk> ObjectList(<js>"..."</js>);
    * 
    *    <jc>// Value converted to a linked-list of strings.</jc>
    *    List&lt;String&gt; l1 = l.get(1, LinkedList.<jk>class</jk>, String.<jk>class</jk>);
    * 
    *    <jc>// Value converted to a linked-list of beans.</jc>
    *    List&lt;MyBean&gt; l2 = l.get(2, LinkedList.<jk>class</jk>, MyBean.<jk>class</jk>);
    * 
    *    <jc>// Value converted to a linked-list of linked-lists of strings.</jc>
    *    List&lt;List&lt;String&gt;&gt; l3 = l.get(3, LinkedList.<jk>class</jk>, LinkedList.<jk>class</jk>, String.<jk>class</jk>);
    * 
    *    <jc>// Value converted to a map of string keys/values.</jc>
    *    Map&lt;String,String&gt; m1 = l.get(4, TreeMap.<jk>class</jk>, String.<jk>class</jk>, String.<jk>class</jk>);
    * 
    *    <jc>// Value converted to a map containing string keys and values of lists containing beans.</jc>
    *    Map&lt;String,List&lt;MyBean&gt;&gt; m2 = l.get(5, TreeMap.<jk>class</jk>, String.<jk>class</jk>, List.<jk>class</jk>, MyBean.<jk>class</jk>);
    * </p>
    * 
    * <p>
    * <code>Collection</code> classes are assumed to be followed by zero or one objects indicating the element type.
    * 
    * <p>
    * <code>Map</code> classes are assumed to be followed by zero or two meta objects indicating the key and value types.
    * 
    * <p>
    * The array can be arbitrarily long to indicate arbitrarily complex data structures.
    * 
    * <p>
    * See {@link BeanSession#convertToType(Object, ClassMeta)} for the list of valid data conversions.
    * 
    * @param index The index into this list.
    * @param type The type of object to convert the entry to.
    * @param args The type arguments of the type to convert the entry to.
    * @param <T> The type of object to convert the entry to.
    * @return The converted entry.
    */
   public <T> T get(int index, Type type, Type...args) {
      return session.convertToType(get(index), type, args);
   }

   /**
    * Shortcut for calling <code>get(index, String.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    */
   public String getString(int index) {
      return get(index, String.class);
   }

   /**
    * Shortcut for calling <code>get(index, Integer.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public Integer getInt(int index) {
      return get(index, Integer.class);
   }

   /**
    * Shortcut for calling <code>get(index, Boolean.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public Boolean getBoolean(int index) {
      return get(index, Boolean.class);
   }

   /**
    * Shortcut for calling <code>get(index, Long.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public Long getLong(int index) {
      return get(index, Long.class);
   }

   /**
    * Shortcut for calling <code>get(index, Map.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public Map<?,?> getMap(int index) {
      return get(index, Map.class);
   }

   /**
    * Same as {@link #getMap(int)} except converts the keys and values to the specified types.
    * 
    * @param index The index.
    * @param keyType The key type class.
    * @param valType The value type class.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public <K,V> Map<K,V> getMap(int index, Class<K> keyType, Class<V> valType) {
      return session.convertToType(get(index), Map.class, keyType, valType);
   }

   /**
    * Shortcut for calling <code>get(index, List.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public List<?> getList(int index) {
      return get(index, List.class);
   }

   /**
    * Same as {@link #getList(int)} except converts the elements to the specified types.
    * 
    * @param index The index.
    * @param elementType The element type class.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public <E> List<E> getList(int index, Class<E> elementType) {
      return session.convertToType(get(index), List.class, elementType);
   }

   /**
    * Shortcut for calling <code>get(index, ObjectMap.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public ObjectMap getObjectMap(int index) {
      return get(index, ObjectMap.class);
   }

   /**
    * Shortcut for calling <code>get(index, ObjectList.<jk>class</jk>)</code>.
    * 
    * @param index The index.
    * @return The converted value.
    * @throws InvalidDataConversionException If value cannot be converted.
    */
   public ObjectList getObjectList(int index) {
      return get(index, ObjectList.class);
   }

   /**
    * Same as {@link #get(int,Class) get(int,Class)}, but the key is a slash-delimited path used to traverse entries in
    * this POJO.
    * 
    * <p>
    * For example, the following code is equivalent:
    * </p>
    * <p class='bcode'>
    *    ObjectMap m = getObjectMap();
    * 
    *    <jc>// Long way</jc>
    *    <jk>long</jk> l = m.getObjectMap(<js>"foo"</js>).getObjectList(<js>"bar"</js>).getObjectMap(<js>"0"</js>).getLong(<js>"baz"</js>);
    * 
    *    <jc>// Using this method</jc>
    *    <jk>long</jk> l = m.getAt(<js>"foo/bar/0/baz"</js>, <jk>long</jk>.<jk>class</jk>);
    * </p>
    * 
    * <p>
    * This method uses the {@link PojoRest} class to perform the lookup, so the map can contain any of the various
    * class types that the {@link PojoRest} class supports (e.g. beans, collections, arrays).
    * 
    * @param path The path to the entry.
    * @param type The class type.
    * 
    * @param <T> The class type.
    * @return The value, or <jk>null</jk> if the entry doesn't exist.
    */
   public <T> T getAt(String path, Class<T> type) {
      return getPojoRest().get(path, type);
   }

   /**
    * Same as {@link #getAt(String,Class)}, but allows for conversion to complex maps and collections.
    * 
    * @param path The path to the entry.
    * @param type The class type.
    * @param args The class parameter types.
    * 
    * @param <T> The class type.
    * @return The value, or <jk>null</jk> if the entry doesn't exist.
    */
   public <T> T getAt(String path, Type type, Type...args) {
      return getPojoRest().get(path, type, args);
   }

   /**
    * Same as {@link #set(int,Object) set(int,Object)}, but the key is a slash-delimited path used to traverse entries
    * in this POJO.
    * 
    * <p>
    * For example, the following code is equivalent:
    * </p>
    * <p class='bcode'>
    *    ObjectMap m = getObjectMap();
    * 
    *    <jc>// Long way</jc>
    *    m.getObjectMap(<js>"foo"</js>).getObjectList(<js>"bar"</js>).getObjectMap(<js>"0"</js>).put(<js>"baz"</js>, 123);
    * 
    *    <jc>// Using this method</jc>
    *    m.putAt(<js>"foo/bar/0/baz"</js>, 123);
    * </p>
    * 
    * <p>
    * This method uses the {@link PojoRest} class to perform the lookup, so the map can contain any of the various
    * class types that the {@link PojoRest} class supports (e.g. beans, collections, arrays).
    * 
    * @param path The path to the entry.
    * @param o The new value.
    * @return The previous value, or <jk>null</jk> if the entry doesn't exist.
    */
   public Object putAt(String path, Object o) {
      return getPojoRest().put(path, o);
   }

   /**
    * Similar to {@link #putAt(String,Object) putAt(String,Object)}, but used to append to collections and arrays.
    * 
    * <p>
    * For example, the following code is equivalent:
    * </p>
    * <p class='bcode'>
    *    ObjectMap m = getObjectMap();
    * 
    *    <jc>// Long way</jc>
    *    m.getObjectMap(<js>"foo"</js>).getObjectList(<js>"bar"</js>).append(123);
    * 
    *    <jc>// Using this method</jc>
    *    m.postAt(<js>"foo/bar"</js>, 123);
    * </p>
    * 
    * <p>
    * This method uses the {@link PojoRest} class to perform the lookup, so the map can contain any of the various
    * class types that the {@link PojoRest} class supports (e.g. beans, collections, arrays).
    * 
    * @param path The path to the entry.
    * @param o The new value.
    * @return The previous value, or <jk>null</jk> if the entry doesn't exist.
    */
   public Object postAt(String path, Object o) {
      return getPojoRest().post(path, o);
   }

   /**
    * Similar to {@link #remove(int) remove(int)},but the key is a slash-delimited path used to traverse entries in
    * this POJO.
    * 
    * <p>
    * For example, the following code is equivalent:
    * </p>
    * <p class='bcode'>
    *    ObjectMap m = getObjectMap();
    * 
    *    <jc>// Long way</jc>
    *    m.getObjectMap(<js>"foo"</js>).getObjectList(<js>"bar"</js>).getObjectMap(1).remove(<js>"baz"</js>);
    * 
    *    <jc>// Using this method</jc>
    *    m.deleteAt(<js>"foo/bar/0/baz"</js>);
    * </p>
    * 
    * <p>
    * This method uses the {@link PojoRest} class to perform the lookup, so the map can contain any of the various
    * class types that the {@link PojoRest} class supports (e.g. beans, collections, arrays).
    * 
    * @param path The path to the entry.
    * @return The previous value, or <jk>null</jk> if the entry doesn't exist.
    */
   public Object deleteAt(String path) {
      return getPojoRest().delete(path);
   }

   /**
    * Creates an {@link Iterable} with elements of the specified child type.
    * 
    * <p>
    * Attempts to convert the child objects to the correct type if they aren't already the correct type.
    * 
    * <p>
    * The <code>next()</code> method on the returned iterator may throw a {@link InvalidDataConversionException} if
    * the next element cannot be converted to the specified type.
    * 
    * <p>
    * See {@link BeanSession#convertToType(Object, ClassMeta)} for a description of valid conversions.
    * 
    * <h5 class='section'>Example:</h5>
    * <p class='bcode'>
    *    <jc>// Iterate over a list of ObjectMaps.</jc>
    *    ObjectList l = <jk>new</jk> ObjectList(<js>"[{foo:'bar'},{baz:123}]"</js>);
    *    for (ObjectMap m : l.elements(ObjectMap.<jk>class</jk>)) {
    *       <jc>// Do something with m.</jc>
    *    }
    * 
    *    <jc>// Iterate over a list of ints.</jc>
    *    ObjectList l = <jk>new</jk> ObjectList(<js>"[1,2,3]"</js>);
    *    for (Integer i : l.elements(Integer.<jk>class</jk>)) {
    *       <jc>// Do something with i.</jc>
    *    }
    * 
    *    <jc>// Iterate over a list of beans.</jc>
    *    <jc>// Automatically converts to beans.</jc>
    *    ObjectList l = <jk>new</jk> ObjectList(<js>"[{name:'John Smith',age:45}]"</js>);
    *    for (Person p : l.elements(Person.<jk>class</jk>)) {
    *       <jc>// Do something with p.</jc>
    *    }
    * </p>
    * 
    * @param <E> The child object type.
    * @param childType The child object type.
    * @return A new <code>Iterable</code> object over this list.
    */
   public <E> Iterable<E> elements(final Class<E> childType) {
      final Iterator<?> i = iterator();
      return new Iterable<E>() {

         @Override /* Iterable */
         public Iterator<E> iterator() {
            return new Iterator<E>() {

               @Override /* Iterator */
               public boolean hasNext() {
                  return i.hasNext();
               }

               @Override /* Iterator */
               public E next() {
                  return session.convertToType(i.next(), childType);
               }

               @Override /* Iterator */
               public void remove() {
                  i.remove();
               }

            };
         }
      };
   }

   /**
    * Returns the {@link ClassMeta} of the class of the object at the specified index.
    * 
    * @param index An index into this list, zero-based.
    * @return The data type of the object at the specified index, or <jk>null</jk> if the value is null.
    */
   public ClassMeta<?> getClassMeta(int index) {
      return session.getClassMetaForObject(get(index));
   }

   private PojoRest getPojoRest() {
      if (pojoRest == null)
         pojoRest = new PojoRest(this);
      return pojoRest;
   }

   /**
    * Serialize this array to a string using the specified serializer.
    * 
    * @param serializer The serializer to use to convert this object to a string.
    * @return This object as a serialized string.
    * @throws SerializeException If a problem occurred trying to convert the output.
    */
   public String toString(WriterSerializer serializer) throws SerializeException {
      return serializer.serialize(this);
   }

   /**
    * Serialize this array to JSON using the {@link JsonSerializer#DEFAULT} serializer.
    */
   @Override /* Object */
   public String toString() {
      try {
         return this.toString(JsonSerializer.DEFAULT_LAX);
      } catch (SerializeException e) {
         return e.getLocalizedMessage();
      }
   }

   /**
    * Convenience method for serializing this ObjectList to the specified Writer using the JsonSerializer.DEFAULT
    * serializer.
    * 
    * @param w The writer to send the serialized contents of this object.
    * @throws IOException If a problem occurred trying to write to the writer.
    * @throws SerializeException If a problem occurred trying to convert the output.
    */
   public void serializeTo(Writer w) throws IOException, SerializeException {
      JsonSerializer.DEFAULT.serialize(this);
   }
}