ParseException.cs

using Lucene.Net.Support;
using System;
using System.Diagnostics.CodeAnalysis;
#if FEATURE_SERIALIZABLE_EXCEPTIONS
using System.Runtime.Serialization;
using System.Security.Permissions;
#endif
using System.Text;

namespace Lucene.Net.QueryParsers.Classic
{
    /*
     * Licensed to the Apache Software Foundation (ASF) under one or more
     * contributor license agreements.  See the NOTICE file distributed with
     * this work for additional information regarding copyright ownership.
     * The ASF licenses this file to You under the Apache License, Version 2.0
     * (the "License"); you may not use this file except in compliance with
     * the License.  You may obtain a copy of the License at
     *
     *     http://www.apache.org/licenses/LICENSE-2.0
     *
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     */

    /// <summary> 
    /// This exception is thrown when parse errors are encountered.
    /// You can explicitly create objects of this exception type by
    /// calling the method GenerateParseException in the generated
    /// parser.
    /// 
    /// You can modify this class to customize your error reporting
    /// mechanisms so long as you retain the public fields.
    /// </summary>
    // LUCENENET: It is no longer good practice to use binary serialization. 
    // See: https://github.com/dotnet/corefx/issues/23584#issuecomment-325724568
#if FEATURE_SERIALIZABLE_EXCEPTIONS
    [Serializable]
#endif
    public class ParseException : Exception
	{
        /// <summary>
        /// This constructor is used by the method GenerateParseException()
        /// in the generated parser.  Calling this constructor generates
        /// a new object of this type with the fields <paramref name="currentToken"/>,
        /// <paramref name="expectedTokenSequences"/>, and <paramref name="tokenImage"/> set.
        /// </summary>
        public ParseException(Token currentToken,
                        int[][] expectedTokenSequences,
                        string[] tokenImage)
            : base(Initialize(currentToken, expectedTokenSequences, tokenImage))
        {
            this.CurrentToken = currentToken;
            this.ExpectedTokenSequences = expectedTokenSequences;
            this.TokenImage = tokenImage;
        }

        /**
         * The following constructors are for use by you for whatever
         * purpose you can think of.  Constructing the exception in this
         * manner makes the exception behave in the normal way - i.e., as
         * documented in the class "Throwable".  The fields "errorToken",
         * "expectedTokenSequences", and "tokenImage" do not contain
         * relevant information.  The JavaCC generated code does not use
         * these constructors.
         */

        public ParseException()
        { }

        public ParseException(string message)
            : base(message)
        { }

        public ParseException(string message, Exception innerException)
            : base(message, innerException)
        { }

#if FEATURE_SERIALIZABLE_EXCEPTIONS
        /// <summary>
        /// Initializes a new instance of this class with serialized data.
        /// </summary>
        /// <param name="info">The <see cref="SerializationInfo"/> that holds the serialized object data about the exception being thrown.</param>
        /// <param name="context">The <see cref="StreamingContext"/> that contains contextual information about the source or destination.</param>
        protected ParseException(SerializationInfo info, StreamingContext context)
            : base(info, context)
        {
            CurrentToken = (Token)info.GetValue("CurrentToken", typeof(Token));
            ExpectedTokenSequences = (int[][])info.GetValue("ExpectedTokenSequences", typeof(int[][]));
            TokenImage = (string[])info.GetValue("TokenImage", typeof(string[]));
        }

        [SecurityPermission(SecurityAction.Demand, SerializationFormatter = true)]
        public override void GetObjectData(SerializationInfo info, StreamingContext context)
        {
            base.GetObjectData(info, context);
            info.AddValue("CurrentToken", CurrentToken, typeof(Token));
            info.AddValue("ExpectedTokenSequences", ExpectedTokenSequences, typeof(int[][]));
            info.AddValue("TokenImage", TokenImage, typeof(string[]));
        }
#endif

        /// <summary> 
        /// This is the last token that has been consumed successfully.  If
        /// this object has been created due to a parse error, the token
        /// following this token will (therefore) be the first error token.
        /// </summary>
        public Token CurrentToken { get; set; }

        /// <summary> 
        /// Each entry in this array is an array of integers.  Each array
        /// of integers represents a sequence of tokens (by their ordinal
        /// values) that is expected at this point of the parse.
        /// </summary>
        [WritableArray]
        [SuppressMessage("Microsoft.Performance", "CA1819", Justification = "Lucene's design requires some writable array properties")]
        public int[][] ExpectedTokenSequences { get; set; }

        /// <summary> 
        /// This is a reference to the "tokenImage" array of the generated
        /// parser within which the parse error occurred.  This array is
        /// defined in the generated ...Constants interface.
        /// </summary>
        [WritableArray]
        [SuppressMessage("Microsoft.Performance", "CA1819", Justification = "Lucene's design requires some writable array properties")]
        public string[] TokenImage { get; set; }


        /// <summary>
        /// It uses <paramref name="currentToken"/> and <paramref name="expectedTokenSequences"/> to generate a parse
        /// error message and returns it.  If this object has been created
        /// due to a parse error, and you do not catch it (it gets thrown
        /// from the parser) the correct error message
        /// gets displayed.
        /// </summary>
        private static string Initialize(Token currentToken,
            int[][] expectedTokenSequences,
            string[] tokenImage)
        {

            StringBuilder expected = new StringBuilder();
            int maxSize = 0;
            for (int i = 0; i < expectedTokenSequences.Length; i++)
            {
                if (maxSize < expectedTokenSequences[i].Length)
                {
                    maxSize = expectedTokenSequences[i].Length;
                }
                for (int j = 0; j < expectedTokenSequences[i].Length; j++)
                {
                    expected.Append(tokenImage[expectedTokenSequences[i][j]]).Append(' ');
                }
                if (expectedTokenSequences[i][expectedTokenSequences[i].Length - 1] != 0)
                {
                    expected.Append("...");
                }
                expected.Append(eol).Append("    ");
            }
            string retval = "Encountered \"";
            Token tok = currentToken.Next;
            for (int i = 0; i < maxSize; i++)
            {
                if (i != 0)
                    retval += " ";
                if (tok.Kind == 0)
                {
                    retval += tokenImage[0];
                    break;
                }
                retval += (" " + tokenImage[tok.Kind]);
                retval += " \"";
                retval += AddEscapes(tok.Image);
                retval += " \"";
                tok = tok.Next;
            }
            retval += ("\" at line " + currentToken.Next.BeginLine + ", column " + currentToken.Next.BeginColumn);
            retval += ("." + eol);
            if (expectedTokenSequences.Length == 1)
            {
                retval += ("Was expecting:" + eol + "    ");
            }
            else
            {
                retval += ("Was expecting one of:" + eol + "    ");
            }
            retval += expected.ToString();
            return retval;
        }
		
		/// <summary> 
        /// The end of line string for this machine.
        /// </summary>
		protected static string eol = Environment.NewLine;
		
		/// <summary> 
        /// Used to convert raw characters to their escaped version
		/// when these raw version cannot be used as part of an ASCII
		/// string literal.
		/// </summary>
		internal static string AddEscapes(string str)
		{
			StringBuilder retval = new StringBuilder();
			char ch;
			for (int i = 0; i < str.Length; i++)
			{
				switch (str[i])
				{
					
					case (char) (0): 
						continue;
					
					case '\b': 
						retval.Append("\\b");
						continue;
					
					case '\t': 
						retval.Append("\\t");
						continue;
					
					case '\n': 
						retval.Append("\\n");
						continue;
					
					case '\f': 
						retval.Append("\\f");
						continue;
					
					case '\r': 
						retval.Append("\\r");
						continue;
					
					case '\"': 
						retval.Append("\\\"");
						continue;
					
					case '\'': 
						retval.Append("\\\'");
						continue;
					
					case '\\': 
						retval.Append("\\\\");
						continue;
					
					default: 
						if ((ch = str[i]) < 0x20 || ch > 0x7e)
						{
							string s = "0000" + Convert.ToString(ch, 16);
							retval.Append("\\u" + s.Substring(s.Length - 4, (s.Length) - (s.Length - 4)));
						}
						else
						{
							retval.Append(ch);
						}
						continue;
					
				}
			}
			return retval.ToString();
		}
	}
}