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package org.apache.juneau.parser;

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

import org.apache.juneau.*;
import org.apache.juneau.annotation.*;
import org.apache.juneau.collections.*;
import org.apache.juneau.html.*;
import org.apache.juneau.http.*;
import org.apache.juneau.json.*;
import org.apache.juneau.msgpack.*;
import org.apache.juneau.transform.*;
import org.apache.juneau.transforms.*;
import org.apache.juneau.uon.*;
import org.apache.juneau.utils.*;
import org.apache.juneau.xml.*;

/**
 * Parent class for all Juneau parsers.
 *
 * <h5 class='topic'>Valid data conversions</h5>
 *
 * Parsers can parse any parsable POJO types, as specified in the {@doc PojoCategories}.
 *
 * <p>
 * Some examples of conversions are shown below...
 * </p>
 * <table class='styled'>
 *    <tr>
 *       <th>Data type</th>
 *       <th>Class type</th>
 *       <th>JSON example</th>
 *       <th>XML example</th>
 *       <th>Class examples</th>
 *    </tr>
 *    <tr>
 *       <td>object</td>
 *       <td>Maps, Java beans</td>
 *       <td class='code'>{name:<js>'John Smith'</js>,age:21}</td>
 *       <td class='code'><xt>&lt;object&gt;
 *    &lt;name</xt> <xa>type</xa>=<xs>'string'</xs><xt>&gt;</xt>John Smith<xt>&lt;/name&gt;
 *    &lt;age</xt> <xa>type</xa>=<xs>'number'</xs><xt>&gt;</xt>21<xt>&lt;/age&gt;
 * &lt;/object&gt;</xt></td>
 *       <td class='code'>HashMap, TreeMap&lt;String,Integer&gt;</td>
 *    </tr>
 *    <tr>
 *       <td>array</td>
 *       <td>Collections, Java arrays</td>
 *       <td class='code'>[1,2,3]</td>
 *       <td class='code'><xt>&lt;array&gt;
 *    &lt;number&gt;</xt>1<xt>&lt;/number&gt;
 *    &lt;number&gt;</xt>2<xt>&lt;/number&gt;
 *    &lt;number&gt;</xt>3<xt>&lt;/number&gt;
 * &lt;/array&gt;</xt></td>
 *       <td class='code'>List&lt;Integer&gt;, <jk>int</jk>[], Float[], Set&lt;Person&gt;</td>
 *    </tr>
 *    <tr>
 *       <td>number</td>
 *       <td>Numbers</td>
 *       <td class='code'>123</td>
 *       <td class='code'><xt>&lt;number&gt;</xt>123<xt>&lt;/number&gt;</xt></td>
 *       <td class='code'>Integer, Long, Float, <jk>int</jk></td>
 *    </tr>
 *    <tr>
 *       <td>boolean</td>
 *       <td>Booleans</td>
 *       <td class='code'><jk>true</jk></td>
 *       <td class='code'><xt>&lt;boolean&gt;</xt>true<xt>&lt;/boolean&gt;</xt></td>
 *       <td class='code'>Boolean</td>
 *    </tr>
 *    <tr>
 *       <td>string</td>
 *       <td>CharSequences</td>
 *       <td class='code'><js>'foobar'</js></td>
 *       <td class='code'><xt>&lt;string&gt;</xt>foobar<xt>&lt;/string&gt;</xt></td>
 *       <td class='code'>String, StringBuilder</td>
 *    </tr>
 * </table>
 *
 * <p>
 * In addition, any class types with {@link PojoSwap PojoSwaps} associated with them on the registered
 * bean context can also be passed in.
 *
 * <p>
 * For example, if the {@link TemporalCalendarSwap} transform is used to generalize {@code Calendar} objects to {@code String}
 * objects.
 * When registered with this parser, you can construct {@code Calendar} objects from {@code Strings} using the
 * following syntax...
 * <p class='bcode w800'>
 *    Calendar c = parser.parse(<js>"'Sun Mar 03 04:05:06 EST 2001'"</js>, GregorianCalendar.<jk>class</jk>);
 * </p>
 *
 * <p>
 * If <code>Object.<jk>class</jk></code> is specified as the target type, then the parser automatically determines the
 * data types and generates the following object types...
 * <table class='styled'>
 *    <tr><th>JSON type</th><th>Class type</th></tr>
 *    <tr><td>object</td><td>{@link OMap}</td></tr>
 *    <tr><td>array</td><td>{@link OList}</td></tr>
 *    <tr><td>number</td><td>{@link Number}<br>(depending on length and format, could be {@link Integer},
 *       {@link Double}, {@link Float}, etc...)</td></tr>
 *    <tr><td>boolean</td><td>{@link Boolean}</td></tr>
 *    <tr><td>string</td><td>{@link String}</td></tr>
 * </table>
 */
@ConfigurableContext
public abstract class Parser extends BeanContext {

   /**
    * Represents no Parser.
    */
   public static abstract class Null extends Parser {
      private Null(PropertyStore ps, String[] consumes) {
         super(ps, consumes);
      }
   }

   //-------------------------------------------------------------------------------------------------------------------
   // Configurable properties
   //-------------------------------------------------------------------------------------------------------------------

   static final String PREFIX = "Parser";

   /**
    * Configuration property:  Auto-close streams.
    *
    * <h5 class='section'>Property:</h5>
    * <ul class='spaced-list'>
    *    <li><b>ID:</b>  {@link org.apache.juneau.parser.Parser#PARSER_autoCloseStreams PARSER_autoCloseStreams}
    *    <li><b>Name:</b>  <js>"Parser.autoCloseStreams.b"</js>
    *    <li><b>Data type:</b>  <jk>boolean</jk>
    *    <li><b>System property:</b>  <c>Parser.autoCloseStreams</c>
    *    <li><b>Environment variable:</b>  <c>PARSER_AUTOCLOSESTREAMS</c>
    *    <li><b>Default:</b>  <jk>false</jk>
    *    <li><b>Session property:</b>  <jk>false</jk>
    *    <li><b>Annotations:</b>
    *       <ul>
    *          <li class='ja'>{@link org.apache.juneau.parser.annotation.ParserConfig#autoCloseStreams()}
    *       </ul>
    *    <li><b>Methods:</b>
    *       <ul>
    *          <li class='jm'>{@link org.apache.juneau.parser.ParserBuilder#autoCloseStreams()}
    *       </ul>
    * </ul>
    *
    * <h5 class='section'>Description:</h5>
    *
    * <p>
    * When enabled, <l>InputStreams</l> and <l>Readers</l> passed into parsers will be closed
    * after parsing is complete.
    *
    * <h5 class='section'>Example:</h5>
    * <p class='bcode w800'>
    *    <jc>// Create a parser using strict mode.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .autoCloseStreams()
    *       .build();
    *
    *    <jc>// Same, but use property.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .set(<jsf>PARSER_autoCloseStreams</jsf>, <jk>true</jk>)
    *       .build();
    *
    *    Reader r = <jk>new</jk> FileReader(<js>"/tmp/myfile.json"</js>);
    *    MyBean myBean = p.parse(r, MyBean.<jk>class</jk>);
    *
    *    <jsm>assertTrue</jsm>(r.isClosed());
    * </p>
    */
   public static final String PARSER_autoCloseStreams = PREFIX + ".autoCloseStreams.b";

   /**
    * Configuration property:  Debug output lines.
    *
    * <h5 class='section'>Property:</h5>
    * <ul class='spaced-list'>
    *    <li><b>ID:</b>  {@link org.apache.juneau.parser.Parser#PARSER_debugOutputLines PARSER_debugOutputLines}
    *    <li><b>Name:</b>  <js>"Parser.debugOutputLines.i"</js>
    *    <li><b>Data type:</b>  <jk>int</jk>
    *    <li><b>System property:</b>  <c>Parser.debugOutputLines</c>
    *    <li><b>Environment variable:</b>  <c>PARSER_DEBUGOUTPUTLINES</c>
    *    <li><b>Default:</b>  <c>5</c>
    *    <li><b>Session property:</b>  <jk>false</jk>
    *    <li><b>Annotations:</b>
    *       <ul>
    *          <li class='ja'>{@link org.apache.juneau.parser.annotation.ParserConfig#debugOutputLines()}
    *       </ul>
    *    <li><b>Methods:</b>
    *       <ul>
    *          <li class='jm'>{@link org.apache.juneau.parser.ParserBuilder#debugOutputLines(int)}
    *       </ul>
    * </ul>
    *
    * <h5 class='section'>Description:</h5>
    *
    * <p>
    * When parse errors occur, this specifies the number of lines of input before and after the
    * error location to be printed as part of the exception message.
    *
    * <h5 class='section'>Example:</h5>
    * <p class='bcode w800'>
    *    <jc>// Create a parser whose exceptions print out 100 lines before and after the parse error location.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .debug()  <jc>// Enable debug mode to capture Reader contents as strings.</jc>
    *       .debugOuputLines(100)
    *       .build();
    *
    *    <jc>// Same, but use property.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .set(<jsf>BEAN_debug</jsf>, <jk>true</jk>)
    *       .set(<jsf>PARSER_debugOutputLines</jsf>, 100)
    *       .build();
    *
    *    Reader r = <jk>new</jk> FileReader(<js>"/tmp/mybadfile.json"</js>);
    *    <jk>try</jk> {
    *       p.parse(r, Object.<jk>class</jk>);
    *    } <jk>catch</jk> (ParseException e) {
    *       System.<jsf>err</jsf>.println(e.getMessage());  <jc>// Will display 200 lines of the output.</jc>
    *    }
    * </p>
    */
   public static final String PARSER_debugOutputLines = PREFIX + ".debugOutputLines.i";

   /**
    * Configuration property:  Parser listener.
    *
    * <h5 class='section'>Property:</h5>
    * <ul class='spaced-list'>
    *    <li><b>ID:</b>  {@link org.apache.juneau.parser.Parser#PARSER_listener PARSER_listener}
    *    <li><b>Name:</b>  <js>"Parser.listener.c"</js>
    *    <li><b>Data type:</b>  <c>Class&lt;{@link org.apache.juneau.parser.ParserListener}&gt;</c>
    *    <li><b>Default:</b>  <jk>null</jk>
    *    <li><b>Session property:</b>  <jk>false</jk>
    *    <li><b>Annotations:</b>
    *       <ul>
    *          <li class='ja'>{@link org.apache.juneau.parser.annotation.ParserConfig#listener()}
    *       </ul>
    *    <li><b>Methods:</b>
    *       <ul>
    *          <li class='jm'>{@link org.apache.juneau.parser.ParserBuilder#listener(Class)}
    *       </ul>
    * </ul>
    *
    * <h5 class='section'>Description:</h5>
    *
    * <p>
    * Class used to listen for errors and warnings that occur during parsing.
    *
    * <h5 class='section'>Example:</h5>
    * <p class='bcode w800'>
    *    <jc>// Define our parser listener.</jc>
    *    <jc>// Simply captures all unknown bean property events.</jc>
    *    <jk>public class</jk> MyParserListener <jk>extends</jk> ParserListener {
    *
    *       <jc>// A simple property to store our events.</jc>
    *       <jk>public</jk> List&lt;String&gt; <jf>events</jf> = <jk>new</jk> LinkedList&lt;&gt;();
    *
    *       <ja>@Override</ja>
    *       <jk>public</jk> &lt;T&gt; <jk>void</jk> onUnknownBeanProperty(ParserSession session, ParserPipe pipe, String propertyName, Class&lt;T&gt; beanClass, T bean, <jk>int</jk> line, <jk>int</jk> col) {
    *          <jf>events</jf>.add(propertyName + <js>","</js> + line + <js>","</js> + col);
    *       }
    *    }
    *
    *    <jc>// Create a parser using our listener.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .listener(MyParserListener.<jk>class</jk>)
    *       .build();
    *
    *    <jc>// Same, but use property.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .set(<jsf>PARSER_listener</jsf>, MyParserListener.<jk>class</jk>)
    *       .build();
    *
    *    <jc>// Create a session object.</jc>
    *    <jc>// Needed because listeners are created per-session.</jc>
    *    <jk>try</jk> (ReaderParserSession s = p.createSession()) {
    *
    *       <jc>// Parse some JSON object.</jc>
    *       MyBean myBean = s.parse(<js>"{...}"</js>, MyBean.<jk>class</jk>);
    *
    *       <jc>// Get the listener.</jc>
    *       MyParserListener l = s.getListener(MyParserListener.<jk>class</jk>);
    *
    *       <jc>// Dump the results to the console.</jc>
    *       SimpleJsonSerializer.<jsf>DEFAULT</jsf>.println(l.<jf>events</jf>);
    *    }
    * </p>
    */
   public static final String PARSER_listener = PREFIX + ".listener.c";

   /**
    * Configuration property:  Strict mode.
    *
    * <h5 class='section'>Property:</h5>
    * <ul class='spaced-list'>
    *    <li><b>ID:</b>  {@link org.apache.juneau.parser.Parser#PARSER_strict PARSER_strict}
    *    <li><b>Name:</b>  <js>"Parser.strict.b"</js>
    *    <li><b>Data type:</b>  <jk>boolean</jk>
    *    <li><b>System property:</b>  <c>Parser.strict</c>
    *    <li><b>Environment variable:</b>  <c>PARSER_STRICT</c>
    *    <li><b>Default:</b>  <jk>false</jk>
    *    <li><b>Session property:</b>  <jk>false</jk>
    *    <li><b>Annotations:</b>
    *       <ul>
    *          <li class='ja'>{@link org.apache.juneau.parser.annotation.ParserConfig#strict()}
    *       </ul>
    *    <li><b>Methods:</b>
    *       <ul>
    *          <li class='jm'>{@link org.apache.juneau.parser.ParserBuilder#strict()}
    *       </ul>
    * </ul>
    *
    * <h5 class='section'>Description:</h5>
    *
    * <p>
    * When enabled, strict mode for the parser is enabled.
    *
    * <p>
    * Strict mode can mean different things for different parsers.
    *
    * <table class='styled'>
    *    <tr><th>Parser class</th><th>Strict behavior</th></tr>
    *    <tr>
    *       <td>All reader-based parsers</td>
    *       <td>
    *          When enabled, throws {@link ParseException ParseExceptions} on malformed charset input.
    *          Otherwise, malformed input is ignored.
    *       </td>
    *    </tr>
    *    <tr>
    *       <td>{@link JsonParser}</td>
    *       <td>
    *          When enabled, throws exceptions on the following invalid JSON syntax:
    *          <ul>
    *             <li>Unquoted attributes.
    *             <li>Missing attribute values.
    *             <li>Concatenated strings.
    *             <li>Javascript comments.
    *             <li>Numbers and booleans when Strings are expected.
    *             <li>Numbers valid in Java but not JSON (e.g. octal notation, etc...)
    *          </ul>
    *       </td>
    *    </tr>
    * </table>
    *
    * <h5 class='section'>Example:</h5>
    * <p class='bcode w800'>
    *    <jc>// Create a parser using strict mode.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .strict()
    *       .build();
    *
    *    <jc>// Same, but use property.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .set(<jsf>PARSER_strict</jsf>, <jk>true</jk>)
    *       .build();
    *
    *    <jc>// Use it.</jc>
    *    <jk>try</jk> {
    *       MyBean myBean = p.parse(<js>"{unquotedAttr:'value'}"</js>, MyBean.<jk>class</jk>);
    *    } <jk>catch</jk> (ParseException e) {
    *       <jsm>assertTrue</jsm>(e.getMessage().contains(<js>"Unquoted attribute detected."</js>);
    *    }
    * </p>
    */
   public static final String PARSER_strict = PREFIX + ".strict.b";

   /**
    * Configuration property:  Trim parsed strings.
    *
    * <h5 class='section'>Property:</h5>
    * <ul class='spaced-list'>
    *    <li><b>ID:</b>  {@link org.apache.juneau.parser.Parser#PARSER_trimStrings PARSER_trimStrings}
    *    <li><b>Name:</b>  <js>"Parser.trimStrings.b"</js>
    *    <li><b>Data type:</b>  <jk>boolean</jk>
    *    <li><b>System property:</b>  <c>Parser.trimStrings</c>
    *    <li><b>Environment variable:</b>  <c>PARSER_TRIMSTRINGS</c>
    *    <li><b>Default:</b>  <jk>false</jk>
    *    <li><b>Session property:</b>  <jk>false</jk>
    *    <li><b>Annotations:</b>
    *       <ul>
    *          <li class='ja'>{@link org.apache.juneau.parser.annotation.ParserConfig#trimStrings()}
    *       </ul>
    *    <li><b>Methods:</b>
    *       <ul>
    *          <li class='jm'>{@link org.apache.juneau.parser.ParserBuilder#trimStrings()}
    *       </ul>
    * </ul>
    *
    * <h5 class='section'>Description:</h5>
    *
    * <p>
    * When enabled, string values will be trimmed of whitespace using {@link String#trim()} before being added to
    * the POJO.
    *
    * <h5 class='section'>Example:</h5>
    * <p class='bcode w800'>
    *    <jc>// Create a parser with trim-strings enabled.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .trimStrings()
    *       .build();
    *
    *    <jc>// Same, but use property.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .set(<jsf>PARSER_trimStrings</jsf>, <jk>true</jk>)
    *       .build();
    *
    *    <jc>// Use it.</jc>
    *    String json = <js>"{' foo ':' bar '}"</js>;
    *    Map&lt;String,String&gt; map = p.parse(json, HashMap.<jk>class</jk>, String.<jk>class</jk>, String.<jk>class</jk>);
    *
    *    <jc>// Make sure strings are parsed.</jc>
    *    <jsm>assertEquals</jsm>(<js>"bar"</js>, map.get(<js>"foo"</js>));
    * </p>
    */
   public static final String PARSER_trimStrings = PREFIX + ".trimStrings.b";

   /**
    * Configuration property:  Unbuffered.
    *
    * <h5 class='section'>Property:</h5>
    * <ul class='spaced-list'>
    *    <li><b>ID:</b>  {@link org.apache.juneau.parser.Parser#PARSER_unbuffered PARSER_unbuffered}
    *    <li><b>Name:</b>  <js>"Parser.unbuffered.b"</js>
    *    <li><b>Data type:</b>  <jk>boolean</jk>
    *    <li><b>System property:</b>  <c>Parser.unbuffered</c>
    *    <li><b>Environment variable:</b>  <c>PARSER_UNBUFFERED</c>
    *    <li><b>Default:</b>  <jk>false</jk>
    *    <li><b>Session property:</b>  <jk>false</jk>
    *    <li><b>Annotations:</b>
    *       <ul>
    *          <li class='ja'>{@link org.apache.juneau.parser.annotation.ParserConfig#unbuffered()}
    *       </ul>
    *    <li><b>Methods:</b>
    *       <ul>
    *          <li class='jm'>{@link org.apache.juneau.parser.ParserBuilder#unbuffered()}
    *       </ul>
    * </ul>
    *
    * <h5 class='section'>Description:</h5>
    *
    * <p>
    * When enabled, don't use internal buffering during parsing.
    *
    * <p>
    * This is useful in cases when you want to parse the same input stream or reader multiple times
    * because it may contain multiple independent POJOs to parse.
    * <br>Buffering would cause the parser to read past the current POJO in the stream.
    *
    * <h5 class='section'>Example:</h5>
    * <p class='bcode w800'>
    *    <jc>// Create a parser using strict mode.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .unbuffered()
    *       .build();
    *
    *    <jc>// Same, but use property.</jc>
    *    ReaderParser p = JsonParser
    *       .<jsm>create</jsm>()
    *       .set(<jsf>PARSER_unbuffered</jsf>, <jk>true</jk>)
    *       .build();
    *
    *    <jc>// If you're calling parse on the same input multiple times, use a session instead of the parser directly.</jc>
    *    <jc>// It's more efficient because we don't need to recalc the session settings again. </jc>
    *    ReaderParserSession s = p.createSession();
    *
    *    <jc>// Read input with multiple POJOs</jc>
    *    Reader json = <jk>new</jk> StringReader(<js>"{foo:'bar'}{foo:'baz'}"</js>);
    *    MyBean myBean1 = s.parse(json, MyBean.<jk>class</jk>);
    *    MyBean myBean2 = s.parse(json, MyBean.<jk>class</jk>);
    * </p>
    *
    * <ul class='notes'>
    *    <li>
    *       This only allows for multi-input streams for the following parsers:
    *       <ul>
    *          <li class='jc'>{@link JsonParser}
    *          <li class='jc'>{@link UonParser}
    *       </ul>
    *       It has no effect on the following parsers:
    *       <ul>
    *          <li class='jc'>{@link MsgPackParser} - It already doesn't use buffering.
    *          <li class='jc'>{@link XmlParser}, {@link HtmlParser} - These use StAX which doesn't allow for more than one root element anyway.
    *          <li>RDF parsers - These read everything into an internal model before any parsing begins.
    *       </ul>
    * </ul>
    */
   public static final String PARSER_unbuffered = PREFIX + ".unbuffered.b";

   static Parser DEFAULT = new Parser(PropertyStore.create().build()) {
      @Override
      public ParserSession createSession(ParserSessionArgs args) {
         throw new NoSuchMethodError();
      }
   };

   //-------------------------------------------------------------------------------------------------------------------
   // Instance
   //-------------------------------------------------------------------------------------------------------------------

   private final boolean trimStrings, strict, autoCloseStreams, unbuffered;
   private final int debugOutputLines;
   private final Class<? extends ParserListener> listener;

   /** General parser properties currently set on this parser. */
   private final MediaType[] consumes;

   /**
    * Constructor.
    *
    * @param ps The property store containing all the settings for this object.
    * @param consumes The list of media types that this parser consumes (e.g. <js>"application/json"</js>).
    */
   protected Parser(PropertyStore ps, String...consumes) {
      super(ps);

      trimStrings = getBooleanProperty(PARSER_trimStrings, false);
      strict = getBooleanProperty(PARSER_strict, false);
      autoCloseStreams = getBooleanProperty(PARSER_autoCloseStreams, false);
      debugOutputLines = getIntegerProperty(PARSER_debugOutputLines, 5);
      unbuffered = getBooleanProperty(PARSER_unbuffered, false);
      listener = getClassProperty(PARSER_listener, ParserListener.class, null);
      this.consumes = new MediaType[consumes.length];
      for (int i = 0; i < consumes.length; i++) {
         this.consumes[i] = MediaType.of(consumes[i]);
      }
   }

   @Override /* Context */
   public ParserBuilder builder() {
      return new ParserBuilder(getPropertyStore());
   }

   /**
    * Instantiates a new clean-slate {@link ParserBuilder} object.
    *
    * <p>
    * This is equivalent to simply calling <code><jk>new</jk> ParserBuilder()</code>.
    *
    * <p>
    * Note that this method creates a builder initialized to all default settings, whereas {@link #builder()} copies
    * the settings of the object called on.
    *
    * @return A new {@link ParserBuilder} object.
    */
   public static ParserBuilder create() {
      return new ParserBuilder(PropertyStore.DEFAULT);
   }


   //-----------------------------------------------------------------------------------------------------------------
   // Abstract methods
   //-----------------------------------------------------------------------------------------------------------------

   /**
    * Returns <jk>true</jk> if this parser subclasses from {@link ReaderParser}.
    *
    * @return <jk>true</jk> if this parser subclasses from {@link ReaderParser}.
    */
   public boolean isReaderParser() {
      return true;
   }

   /**
    * Create the session object that will be passed in to the parse method.
    *
    * <p>
    * It's up to implementers to decide what the session object looks like, although typically it's going to be a
    * subclass of {@link ParserSession}.
    *
    * @param args
    *    Runtime arguments.
    * @return The new session.
    */
   public abstract ParserSession createSession(ParserSessionArgs args);


   //-----------------------------------------------------------------------------------------------------------------
   // Other methods
   //-----------------------------------------------------------------------------------------------------------------

   /**
    * Parses input into the specified object 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 w800'>
    *    ReaderParser p = JsonParser.<jsf>DEFAULT</jsf>;
    *
    *    <jc>// Parse into a linked-list of strings.</jc>
    *    List l = p.parse(json, LinkedList.<jk>class</jk>, String.<jk>class</jk>);
    *
    *    <jc>// Parse into a linked-list of beans.</jc>
    *    List l = p.parse(json, LinkedList.<jk>class</jk>, MyBean.<jk>class</jk>);
    *
    *    <jc>// Parse into a linked-list of linked-lists of strings.</jc>
    *    List l = p.parse(json, LinkedList.<jk>class</jk>, LinkedList.<jk>class</jk>, String.<jk>class</jk>);
    *
    *    <jc>// Parse into a map of string keys/values.</jc>
    *    Map m = p.parse(json, TreeMap.<jk>class</jk>, String.<jk>class</jk>, String.<jk>class</jk>);
    *
    *    <jc>// Parse into a map containing string keys and values of lists containing beans.</jc>
    *    Map m = p.parse(json, TreeMap.<jk>class</jk>, String.<jk>class</jk>, List.<jk>class</jk>, MyBean.<jk>class</jk>);
    * </p>
    *
    * <p>
    * <c>Collection</c> classes are assumed to be followed by zero or one objects indicating the element type.
    *
    * <p>
    * <c>Map</c> 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.
    *
    * <ul class='notes'>
    *    <li>
    *       Use the {@link #parse(Object, Class)} method instead if you don't need a parameterized map/collection.
    * </ul>
    *
    * @param <T> The class type of the object to create.
    * @param input
    *    The input.
    *    <br>Character-based parsers can handle the following input class types:
    *    <ul>
    *       <li><jk>null</jk>
    *       <li>{@link Reader}
    *       <li>{@link CharSequence}
    *       <li>{@link InputStream} containing UTF-8 encoded text (or charset defined by
    *          {@link ReaderParser#RPARSER_streamCharset} property value).
    *       <li><code><jk>byte</jk>[]</code> containing UTF-8 encoded text (or charset defined by
    *          {@link ReaderParser#RPARSER_streamCharset} property value).
    *       <li>{@link File} containing system encoded text (or charset defined by
    *          {@link ReaderParser#RPARSER_fileCharset} property value).
    *    </ul>
    *    <br>Stream-based parsers can handle the following input class types:
    *    <ul>
    *       <li><jk>null</jk>
    *       <li>{@link InputStream}
    *       <li><code><jk>byte</jk>[]</code>
    *       <li>{@link File}
    *       <li>{@link CharSequence} containing encoded bytes according to the {@link InputStreamParser#ISPARSER_binaryFormat} setting.
    *    </ul>
    * @param type
    *    The object type to create.
    *    <br>Can be any of the following: {@link ClassMeta}, {@link Class}, {@link ParameterizedType}, {@link GenericArrayType}
    * @param args
    *    The type arguments of the class if it's a collection or map.
    *    <br>Can be any of the following: {@link ClassMeta}, {@link Class}, {@link ParameterizedType}, {@link GenericArrayType}
    *    <br>Ignored if the main type is not a map or collection.
    * @return The parsed object.
    * @throws ParseException Malformed input encountered.
    * @throws IOException Thrown by underlying stream.
    * @see BeanSession#getClassMeta(Type,Type...) for argument syntax for maps and collections.
    */
   public final <T> T parse(Object input, Type type, Type...args) throws ParseException, IOException {
      return createSession().parse(input, type, args);
   }

   /**
    * Same as {@link #parse(Object, Type, Type...)} but since it's a {@link String} input doesn't throw an {@link IOException}.
    *
    * @param <T> The class type of the object being created.
    * @param input
    *    The input.
    *    See {@link #parse(Object, Type, Type...)} for details.
    * @param type
    *    The object type to create.
    *    <br>Can be any of the following: {@link ClassMeta}, {@link Class}, {@link ParameterizedType}, {@link GenericArrayType}
    * @param args
    *    The type arguments of the class if it's a collection or map.
    *    <br>Can be any of the following: {@link ClassMeta}, {@link Class}, {@link ParameterizedType}, {@link GenericArrayType}
    *    <br>Ignored if the main type is not a map or collection.
    * @return The parsed object.
    * @throws ParseException Malformed input encountered.
    */
   public final <T> T parse(String input, Type type, Type...args) throws ParseException {
      return createSession().parse(input, type, args);
   }

   /**
    * Same as {@link #parse(Object, Type, Type...)} except optimized for a non-parameterized class.
    *
    * <p>
    * This is the preferred parse method for simple types since you don't need to cast the results.
    *
    * <h5 class='section'>Examples:</h5>
    * <p class='bcode w800'>
    *    ReaderParser p = JsonParser.<jsf>DEFAULT</jsf>;
    *
    *    <jc>// Parse into a string.</jc>
    *    String s = p.parse(json, String.<jk>class</jk>);
    *
    *    <jc>// Parse into a bean.</jc>
    *    MyBean b = p.parse(json, MyBean.<jk>class</jk>);
    *
    *    <jc>// Parse into a bean array.</jc>
    *    MyBean[] ba = p.parse(json, MyBean[].<jk>class</jk>);
    *
    *    <jc>// Parse into a linked-list of objects.</jc>
    *    List l = p.parse(json, LinkedList.<jk>class</jk>);
    *
    *    <jc>// Parse into a map of object keys/values.</jc>
    *    Map m = p.parse(json, TreeMap.<jk>class</jk>);
    * </p>
    *
    * @param <T> The class type of the object being created.
    * @param input
    *    The input.
    *    See {@link #parse(Object, Type, Type...)} for details.
    * @param type The object type to create.
    * @return The parsed object.
    * @throws ParseException Malformed input encountered.
    * @throws IOException Thrown by the underlying stream.
    */
   public final <T> T parse(Object input, Class<T> type) throws ParseException, IOException {
      return createSession().parse(input, type);
   }

   /**
    * Same as {@link #parse(Object, Class)} but since it's a {@link String} input doesn't throw an {@link IOException}.
    *
    * @param <T> The class type of the object being created.
    * @param input
    *    The input.
    *    See {@link #parse(Object, Type, Type...)} for details.
    * @param type The object type to create.
    * @return The parsed object.
    * @throws ParseException Malformed input encountered.
    */
   public final <T> T parse(String input, Class<T> type) throws ParseException {
      return createSession().parse(input, type);
   }

   /**
    * Same as {@link #parse(Object, Type, Type...)} except the type has already been converted into a {@link ClassMeta}
    * object.
    *
    * <p>
    * This is mostly an internal method used by the framework.
    *
    * @param <T> The class type of the object being created.
    * @param input
    *    The input.
    *    See {@link #parse(Object, Type, Type...)} for details.
    * @param type The object type to create.
    * @return The parsed object.
    * @throws ParseException Malformed input encountered.
    * @throws IOException Thrown by the underlying stream.
    */
   public final <T> T parse(Object input, ClassMeta<T> type) throws ParseException, IOException {
      return createSession().parse(input, type);
   }

   /**
    * Same as {@link #parse(Object, ClassMeta)} but since it's a {@link String} input doesn't throw an {@link IOException}.
    *
    * @param <T> The class type of the object being created.
    * @param input
    *    The input.
    *    See {@link #parse(Object, Type, Type...)} for details.
    * @param type The object type to create.
    * @return The parsed object.
    * @throws ParseException Malformed input encountered.
    */
   public final <T> T parse(String input, ClassMeta<T> type) throws ParseException {
      return createSession().parse(input, type);
   }

   @Override /* Context */
   public ParserSession createSession() {
      return createSession(createDefaultSessionArgs());
   }

   @Override /* Context */
   public final ParserSessionArgs createDefaultSessionArgs() {
      return new ParserSessionArgs().mediaType(getPrimaryMediaType());
   }

   //-----------------------------------------------------------------------------------------------------------------
   // Optional methods
   //-----------------------------------------------------------------------------------------------------------------

   /**
    * Parses the contents of the specified reader and loads the results into the specified map.
    *
    * <p>
    * Reader must contain something that serializes to a map (such as text containing a JSON object).
    *
    * <p>
    * Used in the following locations:
    * <ul class='spaced-list'>
    *    <li>
    *       The various character-based constructors in {@link OMap} (e.g.
    *       {@link OMap#OMap(CharSequence,Parser)}).
    * </ul>
    *
    * @param <K> The key class type.
    * @param <V> The value class type.
    * @param input The input.  See {@link #parse(Object, ClassMeta)} for supported input types.
    * @param m The map being loaded.
    * @param keyType The class type of the keys, or <jk>null</jk> to default to <code>String.<jk>class</jk></code>.
    * @param valueType The class type of the values, or <jk>null</jk> to default to whatever is being parsed.
    * @return The same map that was passed in to allow this method to be chained.
    * @throws ParseException Malformed input encountered.
    * @throws UnsupportedOperationException If not implemented.
    */
   public final <K,V> Map<K,V> parseIntoMap(Object input, Map<K,V> m, Type keyType, Type valueType) throws ParseException {
      return createSession().parseIntoMap(input, m, keyType, valueType);
   }

   /**
    * Parses the contents of the specified reader and loads the results into the specified collection.
    *
    * <p>
    * Used in the following locations:
    * <ul class='spaced-list'>
    *    <li>
    *       The various character-based constructors in {@link OList} (e.g.
    *       {@link OList#OList(CharSequence,Parser)}.
    * </ul>
    *
    * @param <E> The element class type.
    * @param input The input.  See {@link #parse(Object, ClassMeta)} for supported input types.
    * @param c The collection being loaded.
    * @param elementType The class type of the elements, or <jk>null</jk> to default to whatever is being parsed.
    * @return The same collection that was passed in to allow this method to be chained.
    * @throws ParseException Malformed input encountered.
    * @throws UnsupportedOperationException If not implemented.
    */
   public final <E> Collection<E> parseIntoCollection(Object input, Collection<E> c, Type elementType) throws ParseException {
      return createSession().parseIntoCollection(input, c, elementType);
   }

   /**
    * Parses the specified array input with each entry in the object defined by the {@code argTypes}
    * argument.
    *
    * <p>
    * Used for converting arrays (e.g. <js>"[arg1,arg2,...]"</js>) into an {@code Object[]} that can be passed
    * to the {@code Method.invoke(target, args)} method.
    *
    * <p>
    * Used in the following locations:
    * <ul class='spaced-list'>
    *    <li>
    *       Used to parse argument strings in the {@link PojoIntrospector#invokeMethod(Method, Reader)} method.
    * </ul>
    *
    * @param input The input.  Subclasses can support different input types.
    * @param argTypes Specifies the type of objects to create for each entry in the array.
    * @return An array of parsed objects.
    * @throws ParseException Malformed input encountered.
    */
   public final Object[] parseArgs(Object input, Type[] argTypes) throws ParseException {
      if (argTypes == null || argTypes.length == 0)
         return new Object[0];
      return createSession().parseArgs(input, argTypes);
   }


   //-----------------------------------------------------------------------------------------------------------------
   // Other methods
   //-----------------------------------------------------------------------------------------------------------------

   /**
    * Returns the media types handled based on the values passed to the <c>consumes</c> constructor parameter.
    *
    * @return The list of media types.  Never <jk>null</jk>.
    */
   public final MediaType[] getMediaTypes() {
      return consumes;
   }

   /**
    * Returns the first media type handled based on the values passed to the <c>consumes</c> constructor parameter.
    *
    * @return The media type.
    */
   public final MediaType getPrimaryMediaType() {
      return consumes == null || consumes.length == 0 ? null : consumes[0];
   }

   /**
    * Returns <jk>true</jk> if this parser can handle the specified content type.
    *
    * @param contentType The content type to test.
    * @return <jk>true</jk> if this parser can handle the specified content type.
    */
   public boolean canHandle(String contentType) {
      if (contentType != null)
         for (MediaType mt : getMediaTypes())
            if (contentType.equals(mt.toString()))
               return true;
      return false;
   }

   //-----------------------------------------------------------------------------------------------------------------
   // Properties
   //-----------------------------------------------------------------------------------------------------------------

   /**
    * Auto-close streams.
    *
    * @see #PARSER_autoCloseStreams
    * @return
    *    <jk>true</jk> if <l>InputStreams</l> and <l>Readers</l> passed into parsers will be closed
    *    after parsing is complete.
    */
   protected final boolean isAutoCloseStreams() {
      return autoCloseStreams;
   }

   /**
    * Debug output lines.
    *
    * @see #PARSER_debugOutputLines
    * @return
    *    The number of lines of input before and after the error location to be printed as part of the exception message.
    */
   protected final int getDebugOutputLines() {
      return debugOutputLines;
   }

   /**
    * Parser listener.
    *
    * @see #PARSER_listener
    * @return
    *    Class used to listen for errors and warnings that occur during parsing.
    */
   protected final Class<? extends ParserListener> getListener() {
      return listener;
   }

   /**
    * Strict mode.
    *
    * @see #PARSER_strict
    * @return
    *    <jk>true</jk> if strict mode for the parser is enabled.
    */
   protected final boolean isStrict() {
      return strict;
   }

   /**
    * Trim parsed strings.
    *
    * @see #PARSER_trimStrings
    * @return
    *    <jk>true</jk> if string values will be trimmed of whitespace using {@link String#trim()} before being added to
    *    the POJO.
    */
   protected final boolean isTrimStrings() {
      return trimStrings;
   }

   /**
    * Unbuffered.
    *
    * @see #PARSER_unbuffered
    * @return
    *    <jk>true</jk> if parsers don't use internal buffering during parsing.
    */
   protected final boolean isUnbuffered() {
      return unbuffered;
   }

   //-----------------------------------------------------------------------------------------------------------------
   // Other methods
   //-----------------------------------------------------------------------------------------------------------------

   @Override /* Context */
   public OMap toMap() {
      return super.toMap()
         .a("Parser", new DefaultFilteringOMap()
            .a("autoCloseStreams", autoCloseStreams)
            .a("debugOutputLines", debugOutputLines)
            .a("listener", listener)
            .a("strict", strict)
            .a("trimStrings", trimStrings)
            .a("unbuffered", unbuffered)
         );
   }
}