ddfsubfielddefinition.java

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            return nLength;
        }
    }

    /**
     * Extract a zero terminated string containing the data for this
     * subfield. Given a pointer to the data for this subfield (from
     * within a DDFRecord) this method will return the data for this
     * subfield. The number of bytes consumed as part of this field
     * can also be fetched. This number may be one longer than the
     * string length if there is a terminator character used.
     * <p>
     * 
     * This function will return the raw binary data of a subfield for
     * types other than DDFString, including data past zero chars.
     * This is the standard way of extracting DDFBinaryString
     * subfields for instance.
     * <p>
     * 
     * @param pachSourceData The pointer to the raw data for this
     *        field. This may have come from DDFRecord::GetData(),
     *        taking into account skip factors over previous subfields
     *        data.
     * @param nMaxBytes The maximum number of bytes that are
     *        accessable after pachSourceData.
     * @param pnConsumedBytes Pointer to an integer into which the
     *        number of bytes consumed by this field should be
     *        written. May be null to ignore. This is used as a skip
     *        factor to increment pachSourceData to point to the next
     *        subfields data.
     * 
     * @return A pointer to a buffer containing the data for this
     *         field. The returned pointer is to an internal buffer
     *         which is invalidated on the next ExtractStringData()
     *         call on this DDFSubfieldDefn(). It should not be freed
     *         by the application.
     */
    String extractStringData(byte[] pachSourceData, int nMaxBytes,
                             MutableInt pnConsumedBytes) {
        int oldConsumed = 0;
        if (pnConsumedBytes != null) {
            oldConsumed = pnConsumedBytes.value;
        }

        int nLength = getDataLength(pachSourceData, nMaxBytes, pnConsumedBytes);
        String ns = new String(pachSourceData, 0, nLength);

        if (Debug.debugging("iso8211detail")) {
            Debug.output("        extracting string data from " + nLength
                    + " bytes of " + pachSourceData.length + ": " + ns
                    + ": consumed " + pnConsumedBytes.value + " vs. "
                    + oldConsumed + ", max = " + nMaxBytes);
        }

        return ns;
    }

    /**
     * Extract a subfield value as a float. Given a pointer to the
     * data for this subfield (from within a DDFRecord) this method
     * will return the floating point data for this subfield. The
     * number of bytes consumed as part of this field can also be
     * fetched. This method may be called for any type of subfield,
     * and will return zero if the subfield is not numeric.
     * 
     * @param pachSourceData The pointer to the raw data for this
     *        field. This may have come from DDFRecord::GetData(),
     *        taking into account skip factors over previous subfields
     *        data.
     * @param nMaxBytes The maximum number of bytes that are
     *        accessable after pachSourceData.
     * @param pnConsumedBytes Pointer to an integer into which the
     *        number of bytes consumed by this field should be
     *        written. May be null to ignore. This is used as a skip
     *        factor to increment pachSourceData to point to the next
     *        subfields data.
     * 
     * @return The subfield's numeric value (or zero if it isn't
     *         numeric).
     */
    public double extractFloatData(byte[] pachSourceData, int nMaxBytes,
                                   MutableInt pnConsumedBytes) {

        switch (pszFormatString.charAt(0)) {
        case 'A':
        case 'I':
        case 'R':
        case 'S':
        case 'C':
            String dataString = extractStringData(pachSourceData,
                    nMaxBytes,
                    pnConsumedBytes);

            if (dataString.equals("")) {
                return 0;
            }

            try {
                return Double.parseDouble(dataString);
            } catch (NumberFormatException nfe) {
                if (Debug.debugging("iso8211")) {
                    Debug.output("DDFSubfieldDefinition.extractFloatData: number format problem: "
                            + dataString);
                }
                return 0;
            }

        case 'B':
        case 'b':
            byte[] abyData = new byte[8];

            if (pnConsumedBytes != null) {
                pnConsumedBytes.value = nFormatWidth;
            }

            if (nFormatWidth > nMaxBytes) {
                Debug.error("DDFSubfieldDefinition: format width is greater than max bytes for float");
                return 0.0;
            }

            // Byte swap the data if it isn't in machine native
            // format. In any event we copy it into our buffer to
            // ensure it is word aligned.
            //
            // DFD - don't think this applies to Java, since it's
            // always big endian

            // if (pszFormatString.charAt(0) == 'B') ||
            // (pszFormatString.charAt(0) == 'b') {
            // for (int i = 0; i < nFormatWidth; i++) {
            // abyData[nFormatWidth-i-1] = pachSourceData[i];
            // }
            // } else {
            System.arraycopy(pachSourceData, 0, abyData, 0, nFormatWidth);
            // }

            // Interpret the bytes of data.
            switch (eBinaryFormat) {
            case DDFBinaryFormat.UInt:
            case DDFBinaryFormat.SInt:
            case DDFBinaryFormat.FloatReal:
                return (double) MoreMath.BuildIntegerBE(abyData);

            // if (nFormatWidth == 1)
            // return(abyData[0]);
            // else if (nFormatWidth == 2)
            // return(*((GUInt16 *) abyData));
            // else if (nFormatWidth == 4)
            // return(*((GUInt32 *) abyData));
            // else {
            // return 0.0;
            // }

            // case DDFBinaryFormat.SInt:
            // if (nFormatWidth == 1)
            // return(*((signed char *) abyData));
            // else if (nFormatWidth == 2)
            // return(*((GInt16 *) abyData));
            // else if (nFormatWidth == 4)
            // return(*((GInt32 *) abyData));
            // else {
            // return 0.0;
            // }

            // case DDFBinaryFormat.FloatReal:
            // if (nFormatWidth == 4)
            // return(*((float *) abyData));
            // else if (nFormatWidth == 8)
            // return(*((double *) abyData));
            // else {
            // return 0.0;
            // }

            case DDFBinaryFormat.NotBinary:
            case DDFBinaryFormat.FPReal:
            case DDFBinaryFormat.FloatComplex:
                return 0.0;
            }
            break;
        // end of 'b'/'B' case.

        default:

        }

        return 0.0;
    }

    /**
     * Extract a subfield value as an integer. Given a pointer to the
     * data for this subfield (from within a DDFRecord) this method
     * will return the int data for this subfield. The number of bytes
     * consumed as part of this field can also be fetched. This method
     * may be called for any type of subfield, and will return zero if
     * the subfield is not numeric.
     * 
     * @param pachSourceData The pointer to the raw data for this
     *        field. This may have come from DDFRecord::GetData(),
     *        taking into account skip factors over previous subfields
     *        data.
     * @param nMaxBytes The maximum number of bytes that are
     *        accessable after pachSourceData.
     * @param pnConsumedBytes Pointer to an integer into which the
     *        number of bytes consumed by this field should be
     *        written. May be null to ignore. This is used as a skip
     *        factor to increment pachSourceData to point to the next
     *        subfields data.
     * 
     * @return The subfield's numeric value (or zero if it isn't
     *         numeric).
     */
    public int extractIntData(byte[] pachSourceData, int nMaxBytes,
                              MutableInt pnConsumedBytes) {

        switch (pszFormatString.charAt(0)) {
        case 'A':
        case 'I':
        case 'R':
        case 'S':
        case 'C':
            String dataString = extractStringData(pachSourceData,
                    nMaxBytes,
                    pnConsumedBytes);
            if (dataString.equals("")) {
                return 0;
            }

            try {
                return Double.valueOf(dataString).intValue();
            } catch (NumberFormatException nfe) {
                if (Debug.debugging("iso8211")) {
                    Debug.output("DDFSubfieldDefinition.extractIntData: number format problem: "
                            + dataString);
                }
                return 0;
            }

        case 'B':
        case 'b':
            byte[] abyData = new byte[8];
            if (nFormatWidth > nMaxBytes) {
                Debug.error("DDFSubfieldDefinition: format width is greater than max bytes for int");
                return 0;
            }

            if (pnConsumedBytes != null) {
                pnConsumedBytes.value = nFormatWidth;
            }

            System.arraycopy(pachSourceData, 0, abyData, 0, nFormatWidth);

            // Interpret the bytes of data.
            switch (eBinaryFormat) {
            case DDFBinaryFormat.UInt:
            case DDFBinaryFormat.SInt:
            case DDFBinaryFormat.FloatReal:
                return (int) MoreMath.BuildIntegerBE(abyData);

            // case DDFBinaryFormat.UInt:
            // if (nFormatWidth == 4)
            // return((int) *((GUInt32 *) abyData));
            // else if (nFormatWidth == 1)
            // return(abyData[0]);
            // else if (nFormatWidth == 2)
            // return(*((GUInt16 *) abyData));
            // else {
            // CPLAssert(false);
            // return 0;
            // }

            // case DDFBinaryFormat.SInt:
            // if (nFormatWidth == 4)
            // return(*((GInt32 *) abyData));
            // else if (nFormatWidth == 1)
            // return(*((signed char *) abyData));
            // else if (nFormatWidth == 2)
            // return(*((GInt16 *) abyData));
            // else {
            // CPLAssert(false);
            // return 0;
            // }

            // case DDFBinaryFormat.FloatReal:
            // if (nFormatWidth == 4)
            // return((int) *((float *) abyData));
            // else if (nFormatWidth == 8)
            // return((int) *((double *) abyData));
            // else {
            // CPLAssert(false);
            // return 0;
            // }

            case DDFBinaryFormat.NotBinary:
            case DDFBinaryFormat.FPReal:
            case DDFBinaryFormat.FloatComplex:
                return 0;
            }
            break;
        // end of 'b'/'B' case.

        default:
            return 0;
        }

        return 0;
    }

    /**
     * Dump subfield value to debugging file.
     * 
     * @param pachData Pointer to data for this subfield.
     * @param nMaxBytes Maximum number of bytes available in pachData.
     */
    public String dumpData(byte[] pachData, int nMaxBytes) {
        StringBuffer sb = new StringBuffer();
        if (eType == DDFDataType.DDFFloat) {
            sb.append("      Subfield " + pszName + "="
                    + extractFloatData(pachData, nMaxBytes, null) + "\n");
        } else if (eType == DDFDataType.DDFInt) {
            sb.append("      Subfield " + pszName + "="
                    + extractIntData(pachData, nMaxBytes, null) + "\n");
        } else if (eType == DDFDataType.DDFBinaryString) {
            sb.append("      Subfield " + pszName + "="
                    + extractStringData(pachData, nMaxBytes, null) + "\n");
        } else {
            sb.append("      Subfield " + pszName + "="
                    + extractStringData(pachData, nMaxBytes, null) + "\n");
        }
        return sb.toString();
    }

}