protected EncodingInfo getEncodingInfo()

in src/org/apache/xerces/impl/XMLEntityManager.java [2034:2110]
46 lines of code
39 McCabe index (conditional complexity)

    protected EncodingInfo getEncodingInfo(byte[] b4, int count) {

        if (count < 2) {
            return EncodingInfo.UTF_8;
        }

        // UTF-16, with BOM
        int b0 = b4[0] & 0xFF;
        int b1 = b4[1] & 0xFF;
        if (b0 == 0xFE && b1 == 0xFF) {
            // UTF-16, big-endian
            return EncodingInfo.UTF_16_BIG_ENDIAN_WITH_BOM;
        }
        if (b0 == 0xFF && b1 == 0xFE) {
            // UTF-16, little-endian
            return EncodingInfo.UTF_16_LITTLE_ENDIAN_WITH_BOM;
        }

        // default to UTF-8 if we don't have enough bytes to make a
        // good determination of the encoding
        if (count < 3) {
            return EncodingInfo.UTF_8;
        }

        // UTF-8 with a BOM
        int b2 = b4[2] & 0xFF;
        if (b0 == 0xEF && b1 == 0xBB && b2 == 0xBF) {
            return EncodingInfo.UTF_8_WITH_BOM;
        }

        // default to UTF-8 if we don't have enough bytes to make a
        // good determination of the encoding
        if (count < 4) {
            return EncodingInfo.UTF_8;
        }

        // other encodings
        int b3 = b4[3] & 0xFF;
        if (b0 == 0x00 && b1 == 0x00 && b2 == 0x00 && b3 == 0x3C) {
            // UCS-4, big endian (1234)
            return EncodingInfo.UCS_4_BIG_ENDIAN;
        }
        if (b0 == 0x3C && b1 == 0x00 && b2 == 0x00 && b3 == 0x00) {
            // UCS-4, little endian (4321)
            return EncodingInfo.UCS_4_LITTLE_ENDIAN;
        }
        if (b0 == 0x00 && b1 == 0x00 && b2 == 0x3C && b3 == 0x00) {
            // UCS-4, unusual octet order (2143)
            // REVISIT: What should this be?
            return EncodingInfo.UCS_4_UNUSUAL_BYTE_ORDER;
        }
        if (b0 == 0x00 && b1 == 0x3C && b2 == 0x00 && b3 == 0x00) {
            // UCS-4, unusual octect order (3412)
            // REVISIT: What should this be?
            return EncodingInfo.UCS_4_UNUSUAL_BYTE_ORDER;
        }
        if (b0 == 0x00 && b1 == 0x3C && b2 == 0x00 && b3 == 0x3F) {
            // UTF-16, big-endian, no BOM
            // (or could turn out to be UCS-2...
            // REVISIT: What should this be?
            return EncodingInfo.UTF_16_BIG_ENDIAN;
        }
        if (b0 == 0x3C && b1 == 0x00 && b2 == 0x3F && b3 == 0x00) {
            // UTF-16, little-endian, no BOM
            // (or could turn out to be UCS-2...
            return EncodingInfo.UTF_16_LITTLE_ENDIAN;
        }
        if (b0 == 0x4C && b1 == 0x6F && b2 == 0xA7 && b3 == 0x94) {
            // EBCDIC
            // a la xerces1, return CP037 instead of EBCDIC here
            return EncodingInfo.EBCDIC;
        }

        // default encoding
        return EncodingInfo.UTF_8;

    } // getEncodingName(byte[],int):Object[]