com.rathravane.till.data.json.CommentedJsonTokener Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of silt Show documentation
A small collection of classes used in various Rathravane systems.
There is a newer version: 2.1.1
/*
 *	Copyright 2006-2016, Rathravane LLC
 *
 *	Licensed 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.
 */
package com.rathravane.till.data.json;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.StringReader;
import java.util.ArrayList;

import org.json.JSONException;
import org.json.JSONTokener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * An extension of org.json's JSONTokener that strips block and line comments.
 * Use this anywhere a JSONTokener is used and you want to allow comments.

 * Block comments are replaced with a space. Line comments are removed such
 * that the end-of-line remains.
 *  
 * @author [email protected]
 *
 */
public class CommentedJsonTokener extends JSONTokener
{
	public CommentedJsonTokener ( Reader reader )
	{
		super ( new CommentStrippingReader ( reader ) );
	}

	public CommentedJsonTokener ( InputStream inputStream ) throws JSONException
	{
		super ( new CommentStrippingReader ( new InputStreamReader ( inputStream ) ) );
	}

	public CommentedJsonTokener ( String s )
	{
		super ( new CommentStrippingReader ( new StringReader ( s ) ) );
	}

	private enum ReadState
	{
		NORMAL,
		SINGLE_QUOTED_STRING,
		SINGLE_QUOTED_STRING_ESC,
		DOUBLE_QUOTED_STRING,
		DOUBLE_QUOTED_STRING_ESC,
		POSSIBLE_COMMENT,
		LINE_COMMENT,
		BLOCK_COMMENT,
		POSSIBLE_BLOCK_COMMENT_END,
		EOF
	}
	
	private static class CommentStrippingReader extends Reader
	{
		public CommentStrippingReader ( Reader baseReader )
		{
			fBase = new BufferedReader ( baseReader );
			fState = ReadState.NORMAL;
			fPendingOut = new ArrayList ();
		}

	    /**
	     * Reads characters into a portion of an array.  This method will block
	     * until some input is available, an I/O error occurs, or the end of the
	     * stream is reached.
	     *
	     * @param      cbuf  Destination buffer
	     * @param      off   Offset at which to start storing characters
	     * @param      len   Maximum number of characters to read
	     *
	     * @return     The number of characters read, or -1 if the end of the
	     *             stream has been reached
	     *
	     * @exception  IOException  If an I/O error occurs
	     */
		@Override
		public int read ( char[] cbuf, int off, int len ) throws IOException
		{
			// if all data has been delivered and the base stream says we're EOF, we're done
			if ( fPendingOut.size () == 0 && fState == ReadState.EOF ) return -1;

			// if the caller asked for 0 bytes, return that.
			if ( len < 1 ) return 0;

			// is there pending output?
			int trx = Math.min ( fPendingOut.size (), len );
			if ( trx > 0 )
			{
				for ( int i=0; i 0 )
			{
				for ( int i=0; i fPendingOut;
	}

	private static final Logger log = LoggerFactory.getLogger ( CommentedJsonTokener.class );
}