public int read()

in chill-java/src/main/java/com/twitter/chill/Base64.java [1706:1799]
68 lines of code
18 McCabe index (conditional complexity)

        public int read() throws java.io.IOException  {

            // Do we need to get data?
            if( position < 0 ) {
                if( encode ) {
                    byte[] b3 = new byte[3];
                    int numBinaryBytes = 0;
                    for( int i = 0; i < 3; i++ ) {
                        int b = in.read();

                        // If end of stream, b is -1.
                        if( b >= 0 ) {
                            b3[i] = (byte)b;
                            numBinaryBytes++;
                        } else {
                            break; // out of for loop
                        }   // end else: end of stream

                    }   // end for: each needed input byte

                    if( numBinaryBytes > 0 ) {
                        encode3to4( b3, 0, numBinaryBytes, buffer, 0, options );
                        position = 0;
                        numSigBytes = 4;
                    }   // end if: got data
                    else {
                        return -1;  // Must be end of stream
                    }   // end else
                }   // end if: encoding

                // Else decoding
                else {
                    byte[] b4 = new byte[4];
                    int i = 0;
                    for( i = 0; i < 4; i++ ) {
                        // Read four "meaningful" bytes:
                        int b = 0;
                        do{ b = in.read(); }
                        while( b >= 0 && decodabet[ b & 0x7f ] <= WHITE_SPACE_ENC );

                        if( b < 0 ) {
                            break; // Reads a -1 if end of stream
                        }   // end if: end of stream

                        b4[i] = (byte)b;
                    }   // end for: each needed input byte

                    if( i == 4 ) {
                        numSigBytes = decode4to3( b4, 0, buffer, 0, options );
                        position = 0;
                    }   // end if: got four characters
                    else if( i == 0 ){
                        return -1;
                    }   // end else if: also padded correctly
                    else {
                        // Must have broken out from above.
                        throw new java.io.IOException( "Improperly padded Base64 input." );
                    }   // end

                }   // end else: decode
            }   // end else: get data

            // Got data?
            if( position >= 0 ) {
                // End of relevant data?
                if( /*!encode &&*/ position >= numSigBytes ){
                    return -1;
                }   // end if: got data

                if( encode && breakLines && lineLength >= MAX_LINE_LENGTH ) {
                    lineLength = 0;
                    return '\n';
                }   // end if
                else {
                    lineLength++;   // This isn't important when decoding
                                    // but throwing an extra "if" seems
                                    // just as wasteful.

                    int b = buffer[ position++ ];

                    if( position >= bufferLength ) {
                        position = -1;
                    }   // end if: end

                    return b & 0xFF; // This is how you "cast" a byte that's
                                     // intended to be unsigned.
                }   // end else
            }   // end if: position >= 0

            // Else error
            else {
                throw new java.io.IOException( "Error in Base64 code reading stream." );
            }   // end else
        }   // end read