spatialindex.java

openmap java写的开源数字地图程序. 用applet实现,可以像google map 那样放大缩小地图.

        }
    }

    /**
     * Creates a spatial index for a shape file. Reads the records
     * from the shape file, writing appropriate index records to the
     * spatial index file.
     * 
     * @param inFile the shape file
     * @param outFile the spatial index file
     */
    public static void createIndex(String inFile, String outFile) {
        byte fileHeader[] = new byte[SHAPE_FILE_HEADER_LENGTH];
        FileInputStream shp = null;
        FileOutputStream ssx = null;
        int shapeType;
        try {
            shp = new FileInputStream(inFile);
            ssx = new FileOutputStream(outFile);
            shp.read(fileHeader, 0, SHAPE_FILE_HEADER_LENGTH);
            ssx.write(fileHeader, 0, SHAPE_FILE_HEADER_LENGTH);
            shapeType = readLEInt(fileHeader, 32);
            switch (shapeType) {
            case SHAPE_TYPE_NULL:
                Debug.error("Unable to index shape type NULL");
                break;
            case SHAPE_TYPE_POINT:
                indexPoints(shp, SHAPE_FILE_HEADER_LENGTH, ssx);
                break;
            case SHAPE_TYPE_ARC:
                //          case SHAPE_TYPE_POLYLINE:
                indexPolygons(shp, SHAPE_FILE_HEADER_LENGTH, ssx);
                break;
            case SHAPE_TYPE_POLYGON:
                indexPolygons(shp, SHAPE_FILE_HEADER_LENGTH, ssx);
                break;
            case SHAPE_TYPE_MULTIPOINT:
                Debug.error("Shapefile SpatialIndex: Unable to index shape type MULTIPOINT");
                break;
            default:
                Debug.error("Shapefile SpatialIndex.createIndex:  Unknown shape type: "
                        + shapeType);
            }

        } catch (java.io.IOException e) {
            e.printStackTrace();
        } finally {
            try {
                shp.close();
                ssx.close();
            } catch (java.io.IOException e) {
            }
        }
    }

    /**
     * Prints a usage statement describing how to use this class from
     * the command line.
     * 
     * @param out The output stream to use for output
     */
    public static void printUsage(PrintStream out) {
        String className = SpatialIndex.class.getName();

        out.println("Usage:");
        out.println();
        out.println("java " + className + " -c file.ssx file.shp");
        out.println("Creates spatial index <file.ssx> from "
                + "shape file <file.shp>.");
        out.println();
        out.println("java " + className + " -d file.ssx");
        out.println("Dumps spatial index information, excluding "
                + "bounding boxes to stdout.  Useful for "
                + "comparing to a shape index.");
        out.println();
        out.println("java " + className + " -d -b file.ssx");
        out.println("Dumps spatial index information including "
                + "bounding boxes to stdout.");
        out.println();
    }

    /**
     * Locate file 'fileName' in classpath, if it is not an absolute
     * file name.
     * 
     * @return absolute name of the file as a string if found, null
     *         otherwise.
     */
    public static String locateFile(String name) {
        File file = new File(name);
        if (file.exists()) {
            return name;
        } else {
            java.net.URL url = ClassLoader.getSystemResource(name);

            //OK, now we want to look around for the file, in the
            //classpaths, and as a resource. It may be a file in
            //a classpath, available for direct access.
            if (url != null) {
                String newname = url.getFile();
                file = new File(newname);
                if (file.exists()) {
                    return newname;
                }
            }
        }
        return null;
    }

    /**
     * Create a SpatialIndex object with just a shape file name. If
     * the shape file is local, this method will attempt to build the
     * spatial index file and place it next to the shape file.
     */
    public static SpatialIndex locateAndSetShapeData(String shapeFileName) {
        SpatialIndex spi = null;
        int appendixIndex = shapeFileName.indexOf(".shp");
        String spatialIndexFileName, newShapeFileName, newSpatialIndexFileName;

        if (Debug.debugging("shape")) {
            Debug.output("SpatialIndex: created with just the shape file "
                    + shapeFileName);
        }

        if (appendixIndex != -1) {

            if (BinaryFile.exists(shapeFileName)) {
                // OK, the shape files exists - now look for spatial
                // index file next to it.
                spatialIndexFileName = shapeFileName.substring(0, appendixIndex)
                        + ".ssx";

                // Now, see if the spatialIndexFileName exists, and if
                // not, create it.
                if (Debug.debugging("shape")) {
                    Debug.output("Trying to locate spatial index file "
                            + spatialIndexFileName);
                }

                if (!BinaryFile.exists(spatialIndexFileName)) {
                    // OK, the spatial index doesn't exist, but if the
                    // shape file is local, we have a shot at creating
                    // it.
                    newShapeFileName = locateFile(shapeFileName);

                    if (newShapeFileName != null) {
                        // It's Local!!
                        Debug.output("Creating spatial index file: "
                                + spatialIndexFileName);

                        appendixIndex = newShapeFileName.indexOf(".shp");
                        newSpatialIndexFileName = newShapeFileName.substring(0,
                                appendixIndex)
                                + ".ssx";
                        SpatialIndex.createIndex(newShapeFileName,
                                newSpatialIndexFileName);
                    } else {
                        Debug.error("Can't create SpatialIndex for URL/JAR shapefile: "
                                + shapeFileName);
                    }
                }

                try {
                    spi = new SpatialIndex(spatialIndexFileName, shapeFileName);
                } catch (java.io.IOException ioe) {
                    Debug.error(ioe.getMessage());
                    ioe.printStackTrace(Debug.getErrorStream());
                    spi = null;
                }
            } else {
                Debug.error("SpatialIndex: Couldn't locate shape file "
                        + shapeFileName);
            }

        } else {
            if (Debug.debugging("shape")) {
                Debug.output("SpatialIndex: file " + shapeFileName
                        + " doesn't look like a shape file");
            }
        }

        return spi;
    }

    public static SpatialIndex locateAndSetShapeData(String shapeFileName,
                                                     String spatialIndexFileName) {
        SpatialIndex spi = null;
        String message = "ShapeLayer SpatialIndex: problem setting up the shape files:\n      shape file: "
                + shapeFileName
                + "\n     spatial index file: "
                + spatialIndexFileName;

        try {
            if (BinaryFile.exists(shapeFileName)
                    && BinaryFile.exists(spatialIndexFileName)) {
                spi = new SpatialIndex(spatialIndexFileName, shapeFileName);
            } else {
                Debug.error(message);
            }
        } catch (java.io.IOException ioe) {
            Debug.error(message + "\n" + ioe.getMessage());
            ioe.printStackTrace(Debug.getErrorStream());
        }
        return spi;
    }

    /**
     * The driver for the command line interface. Reads the command
     * line arguments and executes appropriate calls.
     * <p>
     * See the file documentation for usage.
     * 
     * @param argv the command line arguments
     * @exception IOException if something goes wrong reading or
     *            writing the file
     */
    public static void main(String argv[]) throws IOException {
        int argc = argv.length;

        if (argc == 0) {
            // No arguments, give the user some help
            printUsage(System.out);
            System.exit(0);
        }

        if (argv[0].equals("-d")) {
            if (argc == 2) {
                String name = argv[1];
                SpatialIndex si = new SpatialIndex(name);
                si.dumpIndex(false);
            } else if ((argc == 3) && (argv[1].equals("-b"))) {
                String name = argv[2];
                SpatialIndex si = new SpatialIndex(name);
                si.dumpIndex(true);
            } else {
                printUsage(System.err);
                System.exit(1);
            }
        } else if ((argc == 3) && argv[0].equals("-c")) {
            String indexFile = argv[1];
            String shapeFile = argv[2];
            SpatialIndex.createIndex(shapeFile, indexFile);
        } else {
            printUsage(System.err);
            System.exit(1);
        }
    }

    /**
     * Set the icon to use for point objects, in general.
     * 
     * @param ii ImageIcon to use for icon.
     */
    public synchronized void setPointIcon(ImageIcon ii) {
        pointIcon = ii;
    }

    /**
     * Get the icon used for general point objects.
     * 
     * @return ImageIcon, null if not set.
     */
    public synchronized ImageIcon getPointIcon() {
        return pointIcon;
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.bbn.openmap.io.Closable#close(boolean)
     */
    public boolean close(boolean done) {
        try {
            if (shp != null) {
                shp.close();
            }

            if (ssx != null) {
                ssx.close();
            }
            
            return true;
        } catch (IOException ioe) {

        }

        return false;
    }
}