question: protected char scanSurrogates ( ) { if ( surrogatesSupported && Character . isHighSurrogate ( ch ) ) { char high = ch ; scanChar ( ) ; if ( Character . isLowSurrogate ( ch ) ) { return high ; } ch = high ; } return 0 ; }
target:  Scan surrogate pairs.  If 'ch' is a high surrogate and the next character is a low surrogate, then put the low surrogate in 'ch', and return the high surrogate. otherwise, just return 0.