src/Lucene.Net/Support/IO/SafeTextWriterWrapper.cs

using System;
using System.IO;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;

namespace Lucene.Net.Support.IO
{
    /*
     * 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>
    /// Decorates a <see cref="TextWriter"/> instance and
    /// makes no assumptions about whether <see cref="IDisposable.Dispose"/>
    /// has been called on the inner instance or not. Acts like a circuit breaker -
    /// the first <see cref="ObjectDisposedException"/> caught turns it off and
    /// the rest of the calls are ignored after that point until <see cref="Reset"/>
    /// is called.
    /// <para/>
    /// The primary purpose is for using a <see cref="TextWriter"/> instance within a non-disposable
    /// parent object. Since the creator of the <see cref="TextWriter"/> ultimately is responsible for
    /// disposing it, our non-disposable object has no way of knowing whether it is safe to use the <see cref="TextWriter"/>.
    /// Wraping the <see cref="TextWriter"/> within a <see cref="SafeTextWriterWrapper"/> ensures the
    /// non-disposable object can continue to make calls to the <see cref="TextWriter"/> without raising
    /// exceptions (it is presumed that the <see cref="TextWriter"/> functionality is optional).
    /// </summary>
    internal class SafeTextWriterWrapper : TextWriter
    {
        private readonly TextWriter textWriter;
        private bool isDisposed = false;

        public SafeTextWriterWrapper(TextWriter textWriter)
        {
            this.textWriter = textWriter ?? throw new ArgumentNullException(nameof(textWriter));
        }

        public override Encoding Encoding => Run(() => textWriter.Encoding);

        public override IFormatProvider FormatProvider => Run(() => textWriter.FormatProvider);

        public override string NewLine
        {
            get => Run(() => textWriter.NewLine);
            set => Run(() => textWriter.NewLine = value);
        }

#if FEATURE_TEXTWRITER_CLOSE
        public override void Close()
        {
            Run(() => textWriter.Close());
        }
#endif
#if FEATURE_TEXTWRITER_CREATEOBJREF
        public override System.Runtime.Remoting.ObjRef CreateObjRef(Type requestedType)
        {
            return Run(() => textWriter.CreateObjRef(requestedType));
        }
#endif

        public override bool Equals(object obj)
        {
            return Run(() => textWriter.Equals(obj));
        }

        [MethodImpl(MethodImplOptions.NoInlining)]
        public override void Flush()
        {
            Run(() => textWriter.Flush());
        }

        public override Task FlushAsync()
        {
            return Run(() => textWriter.FlushAsync());
        }

        public override int GetHashCode()
        {
            return Run(() => textWriter.GetHashCode());
        }

#if FEATURE_TEXTWRITER_INITIALIZELIFETIMESERVICE
        public override object InitializeLifetimeService()
        {
            return Run(() => textWriter.InitializeLifetimeService());
        }
#endif

        public override string ToString()
        {
            return Run(() => textWriter.ToString());
        }

        public override void Write(bool value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(char value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(char[] buffer)
        {
            Run(() => textWriter.Write(buffer));
        }

        public override void Write(char[] buffer, int index, int count)
        {
            Run(() => textWriter.Write(buffer, index, count));
        }

        public override void Write(decimal value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(double value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(float value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(int value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(long value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(object value)
        {
            Run(() => textWriter.Write(value));
        }

        public override void Write(string format, object arg0)
        {
            Run(() => textWriter.Write(format, arg0));
        }

        public override void Write(string format, object arg0, object arg1)
        {
            Run(() => textWriter.Write(format, arg0, arg1));
        }

        public override void Write(string format, object arg0, object arg1, object arg2)
        {
            Run(() => textWriter.Write(format, arg0, arg1, arg2));
        }

        public override void Write(string format, params object[] arg)
        {
            Run(() => textWriter.Write(format, arg));
        }

        public override void Write(string value)
        {
            Run(() => textWriter.Write(value));
        }

        //[CLSCompliant(false)]
        public override void Write(uint value)
        {
            Run(() => textWriter.Write(value));
        }

        //[CLSCompliant(false)]
        public override void Write(ulong value)
        {
            Run(() => textWriter.Write(value));
        }

        public override Task WriteAsync(char value)
        {
            return Run(() => textWriter.WriteAsync(value));
        }

        public override Task WriteAsync(char[] buffer, int index, int count)
        {
            return Run(() => textWriter.WriteAsync(buffer, index, count));
        }

        public override Task WriteAsync(string value)
        {
            return Run(() => textWriter.WriteAsync(value));
        }

        public override void WriteLine()
        {
            Run(() => textWriter.WriteLine());
        }

        public override void WriteLine(bool value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(char value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(char[] buffer)
        {
            Run(() => textWriter.WriteLine(buffer));
        }

        public override void WriteLine(char[] buffer, int index, int count)
        {
            Run(() => textWriter.WriteLine(buffer, index, count));
        }

        public override void WriteLine(decimal value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(double value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(float value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(int value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(long value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(object value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override void WriteLine(string format, object arg0)
        {
            Run(() => textWriter.WriteLine(format, arg0));
        }

        public override void WriteLine(string format, object arg0, object arg1)
        {
            Run(() => textWriter.WriteLine(format, arg0, arg1));
        }

        public override void WriteLine(string format, object arg0, object arg1, object arg2)
        {
            Run(() => textWriter.WriteLine(format, arg0, arg1, arg2));
        }

        public override void WriteLine(string format, params object[] arg)
        {
            Run(() => textWriter.WriteLine(format, arg));
        }

        public override void WriteLine(string value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        //[CLSCompliant(false)]
        public override void WriteLine(uint value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        //[CLSCompliant(false)]
        public override void WriteLine(ulong value)
        {
            Run(() => textWriter.WriteLine(value));
        }

        public override Task WriteLineAsync()
        {
            return Run(() => textWriter.WriteLineAsync());
        }

        public override Task WriteLineAsync(char value)
        {
            return Run(() => textWriter.WriteLineAsync(value));
        }

        public override Task WriteLineAsync(char[] buffer, int index, int count)
        {
            return Run(() => textWriter.WriteLineAsync(buffer, index, count));
        }

        public override Task WriteLineAsync(string value)
        {
            return Run(() => textWriter.WriteLineAsync(value));
        }

        private void Run(Action method)
        {
            if (isDisposed) return;

            try
            {
                method();
            }
            catch (ObjectDisposedException)
            {
                isDisposed = true;
            }
        }

        private T Run<T>(Func<T> method)
        {
            if (isDisposed) return default;

            try
            {
                return method();
            }
            catch (ObjectDisposedException)
            {
                isDisposed = true;
                return default;
            }
        }

        public virtual void Reset()
        {
            isDisposed = false;
        }

        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                textWriter.Dispose();
            }
        }
    }
}