question: private char stringChar ( ) throws JsonParserException { int c = advanceChar ( ) ; if ( c == - 1 ) throw createParseException ( null , "String was not terminated before end of input" , true ) ; if ( c < 32 ) throw createParseException ( null , "Strings may not contain control characters: 0x" + Integer . toString ( c , 16 ) , false ) ; return ( char ) c ; }
target:  Advances a character, throwing if it is illegal in the context of a JSON string.