/// <summary>
/// Skip until the first non-whitespace character where comments are
/// also treated as whitespace.
/// </summary>
/// <param name="pbr"></param>
/// <exception cref="System.IO.IOException"/>
/// <exception cref="Gavaghan.JSON.JSONException"/>
public override void SkipWhitespace(PushbackReader pbr)
{
for (; ;)
{
int c = pbr.Read();
if (c < 0)
{
break; // bail on EOF
}
if (!IsWhitespace(c))
{
// it's not whitespace, so see if it's the start of a comment
if (c == '/')
{
int next = pbr.Read();
// is it a line comment?
if (next == '/')
{
SkipLineComment(pbr);
continue;
}
// is it a block comment?
else if (next == '*')
{
SkipBlockComment(pbr);
continue;
}
// else, unread - it's the end of the whitespace
pbr.Unread(c);
}
pbr.Unread(c);
break;
}
}
}
/// <summary>
/// Skip to first non-whitespace character.
/// </summary>
/// <param name="pbr">a pushback reader</param>
/// <exception cref="System.IO.IOException"/>
public virtual void SkipWhitespace(PushbackReader pbr)
{
for (; ;)
{
int c = pbr.Read();
if (c < 0)
{
break; // bail on EOF
}
// if non-whitespace found, push it back and exit
if (!IsWhitespace(c))
{
pbr.Unread(c);
break;
}
}
}
/// <summary>
/// Read the JSON value that comes after the whitespace (if any).
/// </summary>
/// <param name="reader"></param>
/// <returns></returns>
/// <exception cref="System.IO.IOException" />
/// <exception cref="Gavaghan.JSON.JSONException" />
public IJSONValue Read(TextReader reader)
{
PushbackReader pbr = new PushbackReader(reader, PushbackBufferSize);
// look for start of value
SkipWhitespace(pbr);
int c = pbr.Read();
// bail out early if EOF
if (c < 0)
{
return(null);
}
pbr.Unread(c);
return(Read("$", pbr));
}
/// <summary>
/// Throw away characters until the line comment is completely read.
/// </summary>
/// <param name="pbr">the PushbackReader to use</param>
/// <exception cref="System.IO.IOException"/>
/// <exception cref="Gavaghan.JSON.JSONException"/>
private void SkipLineComment(PushbackReader pbr)
{
for (; ;)
{
int c = pbr.Read();
// out of data? quit
if (c < 0)
{
break;
}
// end of line? quit
if ((c == '\n') || (c == '\r'))
{
break;
}
}
}
/// <summary>
/// Throw away characters until the block comment is completely read.
/// </summary>
/// <param name="pbr">the PushbackReader to use</param>
/// <exception cref="System.IO.IOException"/>
/// <exception cref="Gavaghan.JSON.JSONException"/>
private void SkipBlockComment(PushbackReader pbr)
{
bool star = false;
for (; ;)
{
int c = pbr.Read();
// out of data? throw exception
if (c < 0)
{
throw new JSONException("$", "Unterminated block comment at end of file");
}
if (star && (c == '/'))
{
break;
}
star = (c == '*');
}
}
