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Echo2 bundled with Echo2_Extras, Echo2_FileTransfer and echopointing and various improvements/bugfixes
/*
* This file is part of the Echo Web Application Framework (hereinafter "Echo").
* Copyright (C) 2002-2009 NextApp, Inc.
*
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*/
package nextapp.echo2.webcontainer.propertyrender;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import nextapp.echo2.app.Extent;
import nextapp.echo2.webrender.output.CssStyle;
/**
* Utility class for rendering nextapp.echo2.app.Extent
* properties to CSS.
*/
public class ExtentRender {
private static final Map UNIT_NAMES_TO_VALUES;
static {
Map m = new HashMap();
m.put("cm", new Integer(Extent.CM));
m.put("em", new Integer(Extent.EM));
m.put("ex", new Integer(Extent.EX));
m.put("in", new Integer(Extent.IN));
m.put("mm", new Integer(Extent.MM));
m.put("pc", new Integer(Extent.PC));
m.put("%", new Integer(Extent.PERCENT));
m.put("pt", new Integer(Extent.PT));
m.put("px", new Integer(Extent.PX));
UNIT_NAMES_TO_VALUES = Collections.unmodifiableMap(m);
}
/**
* Determines if the given Extent is of zero length.
* This method interprets null Extents to be of zero
* length.
*
* @param extent the extent
* @return true if the extent is of zero length
*/
public static boolean isZeroLength(Extent extent) {
return extent == null || extent.getValue() == 0;
}
/**
* Attempts to render a given Extent to a pixel CSS attribute
* value. Returns null if the the extent can not be represented by a pixel
* value.
*
* @param extent the property value
* @return the CSS attribute value
*/
public static final String renderCssAttributePixelValue(Extent extent) {
return renderCssAttributePixelValue(extent, null);
}
/**
* Attempts to render a given Extent to a pixel CSS attribute
* value. Returns the specified invalidValue if the specified
* Extent is not valid.
*
* @param extent the property value
* @return the CSS attribute value to return if the provided value is not a valid
* pixel value
* @return the CSS attribute value
*/
public static final String renderCssAttributePixelValue(Extent extent, String invalidValue) {
if (extent != null && extent.getUnits() == Extent.PX) {
return extent.getValue() + "px";
} else {
return invalidValue;
}
}
/**
* Renders an Extent property value to a CSS dimensioned
* attribute value.
*
* @param extent the property value
* @return the CSS attribute value
*/
public static final String renderCssAttributeValue(Extent extent) {
return extent.getValue() + renderUnits(extent.getUnits());
}
/**
* Renders 1/2 the distance specified by an Extent property
* value to a CSS dimensioned attribute.
* For example, an extent that would normally render as "3px" would be
* rendered as "1.5px" by this method.
*
* @param extent the property value
* @return the CSS attribute value
*/
public static final String renderCssAttributeValueHalf(Extent extent) {
if (extent.getValue() % 2 == 0) {
return (extent.getValue() / 2) + renderUnits(extent.getUnits());
} else {
return (extent.getValue() / 2) + ".5" + renderUnits(extent.getUnits());
}
}
/**
* Renders an Extent property to the given CSS style.
* Null property values are ignored.
*
* @param cssStyle the target CssStyle
* @param cssAttribute the CSS attribute name, e.g., "width" or "height".
* @param extent the property value
*/
public static final void renderToStyle(CssStyle cssStyle, String cssAttribute, Extent extent) {
if (extent == null) {
return;
}
cssStyle.setAttribute(cssAttribute, renderCssAttributeValue(extent));
}
/**
* Renders the given Extent units constant into a CSS
* unit suffix.
*
* @param units the Extent units constant value
* @return the CSS unit suffix
*/
public static final String renderUnits(int units) {
switch (units) {
case Extent.CM: return "cm";
case Extent.EM: return "em";
case Extent.EX: return "ex";
case Extent.IN: return "in";
case Extent.MM: return "mm";
case Extent.PC: return "pc";
case Extent.PERCENT: return "%";
case Extent.PT: return "pt";
case Extent.PX: return "px";
default:
throw new IllegalArgumentException("Invalid extent.");
}
}
private static int getUnitPosition(String s) {
int length = s.length();
for (int i = 0; i < length; ++i) {
char ch = s.charAt(i);
if (ch != '-' && (ch < '0' || ch > '9')) {
return i;
}
}
return -1;
}
/**
* Creates an Extent from the given CSS dimensioned attribute
* value.
*
* @param extentString the CSS dimensioned attribute value
* @return an equivalent Extent, or null if the input
* is not valid.
*/
public static final Extent toExtent(String extentString) {
try {
if (extentString == null) {
return null;
}
int unitPosition = getUnitPosition(extentString);
if (unitPosition == -1) {
return null;
}
String unitString = extentString.substring(unitPosition);
Integer unitInteger = (Integer) UNIT_NAMES_TO_VALUES.get(unitString);
if (unitInteger == null) {
return null;
}
Extent extent = new Extent(Integer.parseInt(extentString.substring(0, unitPosition)), unitInteger.intValue());
return extent;
} catch (NumberFormatException ex) {
return null;
}
}
/**
* Attempts to convert a given Extent to a pixel value.
* Returns defaultPixels if the conversion is not possible.
*
* @param extent the Extent to convert
* @param defaultPixels the pixel value to return if conversion is
* impossible.
* @return the value of the extent in pixels
*/
public static final int toPixels(Extent extent, int defaultPixels) {
if (extent != null && extent.getUnits() == Extent.PX) {
return extent.getValue();
} else {
return defaultPixels;
}
}
/** Non-instantiable class. */
private ExtentRender() { }
}
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