texttable.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.

// **********************************************************************
// 
// <copyright>
// 
//  BBN Technologies
//  10 Moulton Street
//  Cambridge, MA 02138
//  [phone]
// 
//  Copyright (C) BBNT Solutions LLC. All rights reserved.
// 
// </copyright>
// **********************************************************************
// $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/layer/vpf/TextTable.java,v $
// $Revision: 1.4.2.1 $ $Date: 2004/10/14 18:27:22 $ $Author: dietrick $
// **********************************************************************

package com.bbn.openmap.layer.vpf;

import java.util.*;
import com.bbn.openmap.LatLonPoint;
import com.bbn.openmap.io.FormatException;

/**
 * Read VPF format text tables to generate text graphics for OpenMap.
 */
public class TextTable extends PrimitiveTable {

    /** the column that our coordinates are in */
    final private int coordColumn;

    /** the column that the text info is in */
    final private int textColumn;

    /**
     * Construct a TextTable for reading VPF text features.
     * 
     * @param cov the CoverageTable for the tile
     * @param tile the tile to parse
     * @exception FormatException if something goes wrong reading the
     *            text
     */
    public TextTable(CoverageTable cov, TileDirectory tile)
            throws FormatException {
        super(cov, tile, "txt");
        if ((coordColumn = whatColumn("shape_line")) == -1) {
            throw new FormatException("texttable couldn't get "
                    + "shape_line column");
        }
        if ((textColumn = whatColumn("string")) == -1) {
            throw new FormatException("texttable couldn't get "
                    + "string column");
        }
    }

    /**
     * Returns the coordinate string for the text primitive
     * 
     * @param textprim the text primitive
     */
    public CoordFloatString getCoordinates(List textprim) {
        return (CoordFloatString) textprim.get(coordColumn);
    }

    /**
     * Parse the text records for this tile, calling
     * warehouse.createText once for each record in the selection
     * region.
     * 
     * @param warehouse the warehouse used for createText calls (must
     *        not be null)
     * @param dpplat threshold for latitude thinning (passed to
     *        warehouse)
     * @param dpplon threshold for longitude thinngin (passed to
     *        warehouse)
     * @param ll1 upperleft of selection region (passed to warehouse)
     * @param ll2 lowerright of selection region (passed to warehouse)
     * @see VPFGraphicWarehouse#createText
     */
    public void drawTile(VPFGraphicWarehouse warehouse, float dpplat,
                         float dpplon, LatLonPoint ll1, LatLonPoint ll2) {

        float ll1lat = ll1.getLatitude();
        float ll1lon = ll1.getLongitude();
        float ll2lat = ll2.getLatitude();
        float ll2lon = ll2.getLongitude();

        try {
            for (List text = new ArrayList(); parseRow(text);) {
                String textval = (String) text.get(textColumn);
                CoordFloatString coords = (CoordFloatString) text.get(coordColumn);
                float lat = coords.getYasFloat(0);
                float lon = coords.getXasFloat(0);

                if ((lat > ll2lat) && (lat < ll1lat) && (lon > ll1lon)
                        && (lon < ll2lon)) {
                    warehouse.createText(covtable,
                            this,
                            text,
                            lat,
                            lon,
                            textval);
                }
            }
        } catch (FormatException f) {
            System.out.println("Exception: " + f.getClass() + " "
                    + f.getMessage());
        }
    }

    /**
     * Use the warehouse to create a graphic from a feature in the
     * TextTable.
     * 
     * @param warehouse the warehouse used for createText calls (must
     *        not be null)
     * @param dpplat threshold for latitude thinning (passed to
     *        warehouse)
     * @param dpplon threshold for longitude thinngin (passed to
     *        warehouse)
     * @param ll1 upperleft of selection region (passed to warehouse)
     * @param ll2 lowerright of selection region (passed to warehouse)
     * @param text a list with the TextTable row contents.
     * @param featureType the string representing the feature type, in
     *        case the warehouse wants to do some intelligent
     *        rendering.
     * @see VPFGraphicWarehouse#createText
     */
    public void drawFeature(VPFFeatureWarehouse warehouse, float dpplat,
                            float dpplon, LatLonPoint ll1, LatLonPoint ll2,
                            List text, String featureType) {

        if (warehouse == null) {
            return;
        }

        float ll1lat = ll1.getLatitude();
        float ll1lon = ll1.getLongitude();
        float ll2lat = ll2.getLatitude();
        float ll2lon = ll2.getLongitude();

        String textval = (String) text.get(textColumn);
        CoordFloatString coords = (CoordFloatString) text.get(coordColumn);

        float lat = coords.getYasFloat(0);
        float lon = coords.getXasFloat(0);
        if ((lat > ll2lat) && (lat < ll1lat) && (lon > ll1lon)
                && (lon < ll2lon)) {
            warehouse.createText(covtable,
                    this,
                    text,
                    lat,
                    lon,
                    textval,
                    featureType);
        }
    }
}