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/* * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.swing.text.html; import java.awt.Polygon; import java.io.Serializable; import java.util.StringTokenizer; import java.util.Vector; import javax.swing.text.AttributeSet; /** * Map is used to represent a map element that is part of an HTML document. * Once a Map has been created, and any number of areas have been added, * you can test if a point falls inside the map via the contains method. * * @author Scott Violet */ @SuppressWarnings("serial") // Same-version serialization only class Map implements Serializable { /** Name of the Map. */ private String name; /** An array of AttributeSets. */ private Vector<AttributeSet> areaAttributes; /** An array of RegionContainments, will slowly grow to match the * length of areaAttributes as needed. */ private Vector<RegionContainment> areas; public Map() { } public Map(String name) { this.name = name; } /** * Returns the name of the Map. */ public String getName() { return name; } /** * Defines a region of the Map, based on the passed in AttributeSet. */ public void addArea(AttributeSet as) { if (as == null) { return; } if (areaAttributes == null) { areaAttributes = new Vector<AttributeSet>(2); } areaAttributes.addElement(as.copyAttributes()); } /** * Removes the previously created area. */ public void removeArea(AttributeSet as) { if (as != null && areaAttributes != null) { int numAreas = (areas != null) ? areas.size() : 0; for (int counter = areaAttributes.size() - 1; counter >= 0; counter--) { if (areaAttributes.elementAt(counter).isEqual(as)) { areaAttributes.removeElementAt(counter); if (counter < numAreas) { areas.removeElementAt(counter); } } } } } /** * Returns the AttributeSets representing the differet areas of the Map. */ public AttributeSet[] getAreas() { int numAttributes = (areaAttributes != null) ? areaAttributes.size() : 0; if (numAttributes != 0) { AttributeSet[] retValue = new AttributeSet[numAttributes]; areaAttributes.copyInto(retValue); return retValue; } return null; } /** * Returns the AttributeSet that contains the passed in location, * <code>x</code>, <code>y</code>. <code>width</code>, <code>height</code> * gives the size of the region the map is defined over. If a matching * area is found, the AttribueSet for it is returned. */ public AttributeSet getArea(int x, int y, int width, int height) { int numAttributes = (areaAttributes != null) ? areaAttributes.size() : 0; if (numAttributes > 0) { int numAreas = (areas != null) ? areas.size() : 0; if (areas == null) { areas = new Vector<RegionContainment>(numAttributes); } for (int counter = 0; counter < numAttributes; counter++) { if (counter >= numAreas) { areas.addElement(createRegionContainment(areaAttributes.elementAt(counter))); } RegionContainment rc = areas.elementAt(counter); if (rc != null && rc.contains(x, y, width, height)) { return areaAttributes.elementAt(counter); } } } return null; } /** * Creates and returns an instance of RegionContainment that can be * used to test if a particular point lies inside a region. */ protected RegionContainment createRegionContainment(AttributeSet attributes) { Object shape = attributes.getAttribute(HTML.Attribute.SHAPE); if (shape == null) { shape = "rect"; } if (shape instanceof String) { String shapeString = ((String) shape).toLowerCase(); RegionContainment rc = null; try { if (shapeString.equals("rect")) { rc = new RectangleRegionContainment(attributes); } else if (shapeString.equals("circle")) { rc = new CircleRegionContainment(attributes); } else if (shapeString.equals("poly")) { rc = new PolygonRegionContainment(attributes); } else if (shapeString.equals("default")) { rc = DefaultRegionContainment.sharedInstance(); } } catch (RuntimeException re) { // Something wrong with attributes. rc = null; } return rc; } return null; } /** * Creates and returns an array of integers from the String * <code>stringCoords</code>. If one of the values represents a * % the returned value with be negative. If a parse error results * from trying to parse one of the numbers null is returned. */ protected static int[] extractCoords(Object stringCoords) { if (stringCoords == null || !(stringCoords instanceof String)) { return null; } StringTokenizer st = new StringTokenizer((String) stringCoords, ", \t\n\r"); int[] retValue = null; int numCoords = 0; while (st.hasMoreElements()) { String token = st.nextToken(); int scale; if (token.endsWith("%")) { scale = -1; token = token.substring(0, token.length() - 1); } else { scale = 1; } try { int intValue = Integer.parseInt(token); if (retValue == null) { retValue = new int[4]; } else if (numCoords == retValue.length) { int[] temp = new int[retValue.length * 2]; System.arraycopy(retValue, 0, temp, 0, retValue.length); retValue = temp; } retValue[numCoords++] = intValue * scale; } catch (NumberFormatException nfe) { return null; } } if (numCoords > 0 && numCoords != retValue.length) { int[] temp = new int[numCoords]; System.arraycopy(retValue, 0, temp, 0, numCoords); retValue = temp; } return retValue; } /** * Defines the interface used for to check if a point is inside a * region. */ interface RegionContainment { /** * Returns true if the location <code>x</code>, <code>y</code> * falls inside the region defined in the receiver. * <code>width</code>, <code>height</code> is the size of * the enclosing region. */ public boolean contains(int x, int y, int width, int height); } /** * Used to test for containment in a rectangular region. */ static class RectangleRegionContainment implements RegionContainment { /** Will be non-null if one of the values is a percent, and any value * that is non null indicates it is a percent * (order is x, y, width, height). */ float[] percents; /** Last value of width passed in. */ int lastWidth; /** Last value of height passed in. */ int lastHeight; /** Top left. */ int x0; int y0; /** Bottom right. */ int x1; int y1; public RectangleRegionContainment(AttributeSet as) { int[] coords = Map.extractCoords(as.getAttribute(HTML.Attribute.COORDS)); percents = null; if (coords == null || coords.length != 4) { throw new RuntimeException("Unable to parse rectangular area"); } else { x0 = coords[0]; y0 = coords[1]; x1 = coords[2]; y1 = coords[3]; if (x0 < 0 || y0 < 0 || x1 < 0 || y1 < 0) { percents = new float[4]; lastWidth = lastHeight = -1; for (int counter = 0; counter < 4; counter++) { if (coords[counter] < 0) { percents[counter] = Math.abs(coords[counter]) / 100.0f; } else { percents[counter] = -1.0f; } } } } } public boolean contains(int x, int y, int width, int height) { if (percents == null) { return contains(x, y); } if (lastWidth != width || lastHeight != height) { lastWidth = width; lastHeight = height; if (percents[0] != -1.0f) { x0 = (int) (percents[0] * width); } if (percents[1] != -1.0f) { y0 = (int) (percents[1] * height); } if (percents[2] != -1.0f) { x1 = (int) (percents[2] * width); } if (percents[3] != -1.0f) { y1 = (int) (percents[3] * height); } } return contains(x, y); } public boolean contains(int x, int y) { return ((x >= x0 && x <= x1) && (y >= y0 && y <= y1)); } } /** * Used to test for containment in a polygon region. */ static class PolygonRegionContainment extends Polygon implements RegionContainment { /** If any value is a percent there will be an entry here for the * percent value. Use percentIndex to find out the index for it. */ float[] percentValues; int[] percentIndexs; /** Last value of width passed in. */ int lastWidth; /** Last value of height passed in. */ int lastHeight; public PolygonRegionContainment(AttributeSet as) { int[] coords = Map.extractCoords(as.getAttribute(HTML.Attribute.COORDS)); if (coords == null || coords.length == 0 || coords.length % 2 != 0) { throw new RuntimeException("Unable to parse polygon area"); } else { int numPercents = 0; lastWidth = lastHeight = -1; for (int counter = coords.length - 1; counter >= 0; counter--) { if (coords[counter] < 0) { numPercents++; } } if (numPercents > 0) { percentIndexs = new int[numPercents]; percentValues = new float[numPercents]; for (int counter = coords.length - 1, pCounter = 0; counter >= 0; counter--) { if (coords[counter] < 0) { percentValues[pCounter] = coords[counter] / -100.0f; percentIndexs[pCounter] = counter; pCounter++; } } } else { percentIndexs = null; percentValues = null; } npoints = coords.length / 2; xpoints = new int[npoints]; ypoints = new int[npoints]; for (int counter = 0; counter < npoints; counter++) { xpoints[counter] = coords[counter + counter]; ypoints[counter] = coords[counter + counter + 1]; } } } public boolean contains(int x, int y, int width, int height) { if (percentValues == null || (lastWidth == width && lastHeight == height)) { return contains(x, y); } // Force the bounding box to be recalced. bounds = null; lastWidth = width; lastHeight = height; float fWidth = (float) width; float fHeight = (float) height; for (int counter = percentValues.length - 1; counter >= 0; counter--) { if (percentIndexs[counter] % 2 == 0) { // x xpoints[percentIndexs[counter] / 2] = (int) (percentValues[counter] * fWidth); } else { // y ypoints[percentIndexs[counter] / 2] = (int) (percentValues[counter] * fHeight); } } return contains(x, y); } } /** * Used to test for containment in a circular region. */ static class CircleRegionContainment implements RegionContainment { /** X origin of the circle. */ int x; /** Y origin of the circle. */ int y; /** Radius of the circle. */ int radiusSquared; /** Non-null indicates one of the values represents a percent. */ float[] percentValues; /** Last value of width passed in. */ int lastWidth; /** Last value of height passed in. */ int lastHeight; public CircleRegionContainment(AttributeSet as) { int[] coords = Map.extractCoords(as.getAttribute(HTML.Attribute.COORDS)); if (coords == null || coords.length != 3) { throw new RuntimeException("Unable to parse circular area"); } x = coords[0]; y = coords[1]; radiusSquared = coords[2] * coords[2]; if (coords[0] < 0 || coords[1] < 0 || coords[2] < 0) { lastWidth = lastHeight = -1; percentValues = new float[3]; for (int counter = 0; counter < 3; counter++) { if (coords[counter] < 0) { percentValues[counter] = coords[counter] / -100.0f; } else { percentValues[counter] = -1.0f; } } } else { percentValues = null; } } public boolean contains(int x, int y, int width, int height) { if (percentValues != null && (lastWidth != width || lastHeight != height)) { int newRad = Math.min(width, height) / 2; lastWidth = width; lastHeight = height; if (percentValues[0] != -1.0f) { this.x = (int) (percentValues[0] * width); } if (percentValues[1] != -1.0f) { this.y = (int) (percentValues[1] * height); } if (percentValues[2] != -1.0f) { radiusSquared = (int) (percentValues[2] * Math.min(width, height)); radiusSquared *= radiusSquared; } } return (((x - this.x) * (x - this.x) + (y - this.y) * (y - this.y)) <= radiusSquared); } } /** * An implementation that will return true if the x, y location is * inside a rectangle defined by origin 0, 0, and width equal to * width passed in, and height equal to height passed in. */ static class DefaultRegionContainment implements RegionContainment { /** A global shared instance. */ static DefaultRegionContainment si = null; public static DefaultRegionContainment sharedInstance() { if (si == null) { si = new DefaultRegionContainment(); } return si; } public boolean contains(int x, int y, int width, int height) { return (x <= width && x >= 0 && y >= 0 && y <= width); } } }