miffile.java

.mif .mid file read and write

                        coords[p] = readMIFCoordinate();
                    }

                    numpoints = 0;

                    lineStrings[i] = geomFactory.createLineString(coords);
                }

                if ((numsections == 1) && !toGeometryCollection) {
                    return (Geometry) lineStrings[0];
                }

                return (Geometry) geomFactory.createMultiLineString(lineStrings);
            } catch (Exception e) {
                throw new IOException(
                    "Exception reading PLine data from MIF file : "
                    + e.toString());
            }
        }

        /**
         * Reads Region (Polygon) information from the MIF stream
         *
         * @return The (MULTI)POLYGON object
         *
         * @throws IOException Error retrieving geometry from input MIF stream
         */
        private Geometry readRegionObject() throws IOException {
            try {
                int numpolygons = Integer.parseInt(mif.getToken(' ', true));

                Vector polygons = new Vector();

                LinearRing tmpRing = null;
                Polygon shell = null;
                LinearRing shellRing = null;
                Vector holes = null;
                boolean savePolygon;

                // Read all linearrings;
                for (int i = 0; i < numpolygons; i++) {
                    // Read coordinates & create ring
                    int numpoints = Integer.parseInt(mif.getToken(' ', true));
                    Coordinate[] coords = new Coordinate[numpoints + 1];

                    for (int p = 0; p < numpoints; p++) {
                        coords[p] = readMIFCoordinate();
                    }

                    coords[coords.length - 1] = coords[0];
                    tmpRing = geomFactory.createLinearRing(coords);

                    /*
                     * In MIF format a polygon is described as a list of rings, with no info wether
                     * a ring is a hole or a shell, so we have to determine it by checking if
                     * a ring in contained in the previously defined shell
                     */
                    if ((shell != null) && shell.contains(tmpRing)) {
                        holes.add(tmpRing);
                        tmpRing = null; // mark as done
                        savePolygon = (i == (numpolygons - 1));
                    } else {
                        // New polygon, must save previous if it's not the first ring
                        savePolygon = (i > 0);
                    }

                    if (savePolygon) {
                        LinearRing[] h = null;

                        if (holes.size() > 0) {
                            h = new LinearRing[holes.size()];

                            for (int hole = 0; hole < holes.size(); hole++) {
                                h[hole] = (LinearRing) holes.get(hole);
                            }
                        }

                        polygons.add(geomFactory.createPolygon(shellRing, h));

                        shellRing = null;
                    }

                    // Build the polygon needed for testing holes
                    if (tmpRing != null) {
                        shellRing = tmpRing;
                        shell = geomFactory.createPolygon(shellRing, null);
                        holes = new Vector();
                    }
                }

                if (shellRing != null) {
                    polygons.add(geomFactory.createPolygon(shellRing, null));
                }

                try {
                    if ((polygons.size() == 1) && !toGeometryCollection) {
                        return (Polygon) polygons.get(0);
                    }

                    Polygon[] polys = new Polygon[polygons.size()];

                    for (int i = 0; i < polygons.size(); i++) {
                        polys[i] = (Polygon) polygons.get(i);
                    }

                    return geomFactory.createMultiPolygon(polys);
                } catch (TopologyException topexp) {
                    throw new TopologyException(
                        "TopologyException reading Region polygon : "
                        + topexp.toString());
                }
            } catch (Exception e) {
                throw new IOException(
                    "Exception reading Region data from MIF file : "
                    + e.toString());
            }
        }

        /**
         * Reads a couple of coordinates (x,y) from input stream, applying the
         * transform factor if required.
         *
         * @return A Coordinate object, or null if error encountered
         *
         * @throws IOException if couldn't build a valid Coordinate object
         */
        private Coordinate readMIFCoordinate() throws IOException {
            String x;
            String y;

            try {
                x = mif.getToken(' ', true);
                y = mif.getToken();

                if (x.equals("") || y.equals("")) {
                    throw new IOException("End of file.");
                }

                Coordinate result = new Coordinate(Double.parseDouble(x),
                        Double.parseDouble(y));

                if (useTransform) {
                    result.x = (result.x * multX) + sumX;
                    result.y = (result.y * multY) + sumY;
                }

                return result;
            } catch (Exception e) {
                throw new IOException("Error getting coordinates: "
                    + e.toString());
            }
        }

        /**
         * Reads Point information from the MIF stream
         *
         * @return The next POINT object read
         *
         * @throws IOException Error retrieving geometry from input MIF stream
         */
        private Geometry readPointObject() throws IOException {
            return geomFactory.createPoint(readMIFCoordinate());
        }

        /**
         * Reads Line information from the MIF stream
         *
         * @return a LINESTRING object
         *
         * @throws IOException Error retrieving geometry from input MIF stream
         */
        private Geometry readLineObject() throws IOException {
            Coordinate[] cPoints = new Coordinate[2];
            cPoints[0] = readMIFCoordinate();
            cPoints[1] = readMIFCoordinate();

            LineString[] result = { geomFactory.createLineString(cPoints) };

            if (toGeometryCollection) {
                return geomFactory.createMultiLineString(result);
            }

            return result[0];
        }

        private Geometry readTextObject() throws IOException {
            try {
                mifText = mif.getToken(' ', true, true);
            } catch (ParseException e) {
                throw new IOException(e.getMessage());
            }

            Coordinate c1 = readMIFCoordinate();
            Coordinate c2 = readMIFCoordinate();
            Coordinate p = new Coordinate((c1.x + c2.x) / 2, (c1.y + c2.y) / 2);

            return geomFactory.createPoint(p);
        }
    }

    /**
     * <p>
     * MIF FeatureWriter
     * </p>
     */
    private class Writer implements FeatureWriter<SimpleFeatureType, SimpleFeature> {
        private PrintStream outMif = null;
        private PrintStream outMid = null;
        private  FeatureReader<SimpleFeatureType, SimpleFeature> innerReader = null;
        private MIFValueSetter[] fieldValueSetters;
        private SimpleFeature editFeature = null;
        private SimpleFeature originalFeature = null;

        private Writer(PrintStream mif, PrintStream mid, boolean append)
            throws IOException {
            innerReader = getFeatureReader();

            try {
                fieldValueSetters = getValueSetters();
            } catch (SchemaException e) {
                throw new IOException(e.getMessage());
            }

            outMif = mif;
            outMid = mid;

            try {
                if (!append) {
                    outMif.println(exportHeader());
                }
            } catch (Exception e) {
                outMif = null;
                outMid = null;
                throw new IOException(e.getMessage());
            }
        }

        public SimpleFeatureType getFeatureType() {
            return featureType;
        }

        public SimpleFeature next() throws IOException {
            try {
                if (originalFeature != null) {
                    writeFeature(originalFeature); // keep the original
                }

                if (innerReader.hasNext()) {
                    originalFeature = innerReader.next(); // ;
                    editFeature = SimpleFeatureBuilder.copy(originalFeature);
                    } else {
                    originalFeature = null;
                    editFeature = SimpleFeatureBuilder.build(featureType, featureDefaults, null); 
                }

                return editFeature;
            } catch (Exception e) {
                throw new IOException(e.toString());
            }
        }

        public void remove() throws IOException {
            if (editFeature == null) {
                throw new IOException("Current feature is null");
            }

            editFeature = null;
            originalFeature = null;
        }

        public void write() throws IOException {
            if (editFeature == null) {
                throw new IOException("Current feature is null");
            }

            try {
                writeFeature(editFeature);
            } catch (Exception e) {
                editFeature = null;
                throw new IOException("Can't write feature: " + e.toString());
            }

            editFeature = null;
            originalFeature = null;
        }

        public boolean hasNext() throws IOException {
            return innerReader.hasNext();
        }

        public void close() throws IOException {
            while (hasNext())
                next();

            try {
                if (originalFeature != null) {
                    writeFeature(originalFeature); // keep the original
                }
            } catch (Exception e) {
            }

            innerReader.close();
            innerReader = null;

            try {
                if (outMif != null) {
                    outMif.close();
                }

                if (outMid != null) {
                    outMid.close();
                }

                copyFileAndDelete(mifFileOut, mifFile, true);
                copyFileAndDelete(midFileOut, midFile, true);
            } catch (IOException e) {
            } finally {
                outMid = null;
                outMif = null;
            }
        }

        protected void finalize() throws Throwable {
            close();
            super.finalize();
        }

        /**
         * Writes the given Feature to file
         *
         * @param f The feature to write
         *
         * @throws IOException if cannot access file for reading
         * @throws SchemaException if given Feature is not compatible with
         *         MIFFile FeatureType. TODO: private
         */
        public void writeFeature(SimpleFeature f) throws IOException, SchemaException {
            if ((outMif == null) || (outMid == null)) {
                throw new IOException(
                    "Output stream has not been opened for writing.");
            }

            Geometry theGeom = (geomFieldIndex >= 0)
                ? (Geometry) f.getAttribute(geomFieldIndex) : null;
            String outGeom = exportGeometry(theGeom);

            if (outGeom.equals("")) {
                throw new SchemaException("Unsupported geometry type: "
                    + theGeom.getClass().getName());
            }

            outMif.println(outGeom);

            int col;
            String outBuf = "";