/*
* org.openmicroscopy.shoola.env.config.ColorEntry
*
*------------------------------------------------------------------------------
* Copyright (C) 2006 University of Dundee. All rights reserved.
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* This program 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 for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*------------------------------------------------------------------------------
*/
package org.openmicroscopy.shoola.env.config;
//Java imports
import java.awt.Color;
import java.util.HashMap;
import java.util.Map;
import org.w3c.dom.DOMException;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
//Third-party libraries
//Application-internal dependencies
/**
* Handles a <i>structuredEntry</i> of type <i>color</i>.
* The content of the entry is stored in a {@link Color} object, which is
* then returned by the {@link #getValue() getValue} method.
*
* @author Jean-Marie Burel
* <a href="mailto:j.burel@dundee.ac.uk">j.burel@dundee.ac.uk</a>
* @author <br>Andrea Falconi
* <a href="mailto:a.falconi@dundee.ac.uk">
* a.falconi@dundee.ac.uk</a>
* @version 2.2
* <small>
* (<b>Internal version:</b> $Revision$ $Date$)
* </small>
* @since OME2.2
*/
class ColorEntry
extends Entry
{
/**
* The name of the tag, within this <i>structuredEntry</i>, that is used
* to specify the red's component.
*/
private static final String RED_TAG = "red";
/**
* The name of the tag, within this <i>structuredEntry</i>, that is used
* to specify the green's component.
*/
private static final String GREEN_TAG = "green";
/**
* The name of the tag, within this <i>structuredEntry</i>, that is used
* to specify the blue's component.
*/
private static final String BLUE_TAG = "blue";
/**
* Default value for the red component.
* This is the value that we use to create a {@link Color} object if the
* <i>red</i> tag can't be parsed into an integer or if the parsed value
* is not between the {@link #MIN_VALUE}, {@link #MAX_VALUE} interval.
*/
private static final int DEFAULT_RED = 255;
/**
* Default value for the green component.
* This is the value that we use to create a {@link Color} object if the
* <i>red</i> tag can't be parsed into an integer or if the parsed value
* is not between the {@link #MIN_VALUE}, {@link #MAX_VALUE} interval.
*/
private static final int DEFAULT_GREEN = 255;
/**
* Default value for the blue component.
* This is the value that we use to create a {@link Color} object if the
* <i>red</i> tag can't be parsed into an integer or if the parsed value
* is not between the {@link #MIN_VALUE}, {@link #MAX_VALUE} interval.
*/
private static final int DEFAULT_BLUE = 255;
/** The minimum allowed value for a color component. */
private static final int MIN_VALUE = 0;
/** The maximum allowed value for a color component. */
private static final int MAX_VALUE = 255;
/** The color built from the configuration information. */
private Color value;
/**
* Figures out what value for the specified red component to use from
* the configuration information.
* This method tries to parse the value of the corresponding
* red tag into an integer.
* Failing that or if the parsed value is not between the
* {@link #MIN_VALUE}, {@link #MAX_VALUE} interval,
* then the {@link #DEFAULT_RED} is returned.
*
* @param colorAttributes The pairs <i>(tag-name, tag-value)</i> built from
* the tags contained within the entry tag.
* @return See above.
*/
private int getRedComponent(Map<String, String> colorAttributes)
{
String value = (String) colorAttributes.get(RED_TAG);
return parseValue(value, DEFAULT_RED);
}
/**
* Figures out what value for the specified green component to use from
* the configuration information.
* This method tries to parse the value of the corresponding
* green tag into an integer.
* Failing that or if the parsed value is not between the
* {@link #MIN_VALUE}, {@link #MAX_VALUE} interval,
* then the {@link #DEFAULT_GREEN} is returned.
*
* @param colorAttributes The pairs <i>(tag-name, tag-value)</i> built from
* the tags contained within the entry tag.
* @return See above.
*/
private int getGreenComponent(Map<String, String> colorAttributes)
{
String value = (String) colorAttributes.get(GREEN_TAG);
return parseValue(value, DEFAULT_GREEN);
}
/**
* Figures out what value for the specified blue component to use from
* the configuration information.
* This method tries to parse the value of the corresponding
* blue tag into an integer.
* Failing that or if the parsed value is not between the
* {@link #MIN_VALUE}, {@link #MAX_VALUE} interval,
* then the {@link #DEFAULT_BLUE} is returned.
*
* @param colorAttributes The pairs <i>(tag-name, tag-value)</i> built from
* the tags contained within the entry tag.
* @return See above.
*/
private int getBlueComponent(Map<String, String> colorAttributes)
{
String value = (String) colorAttributes.get(BLUE_TAG);
return parseValue(value, DEFAULT_BLUE);
}
/**
* Parse the specified value, if the specified value doesn't correspond
* to a value in the range
* <code>[{@link #MIN_VALUE}, {@link #MAX_VALUE}]</code>,
* the specifed default value is returned.
*
* @param value The value to parse.
* @param defaultValue The default value to set.
* @return See above.
*/
private int parseValue(String value, int defaultValue)
{
int v = defaultValue;
try {
v = Integer.parseInt(value);
if (v < MIN_VALUE || MAX_VALUE < v) v = defaultValue;
} catch (NumberFormatException nfe) {}
return v;
}
/**
* Extracts the values of the tags within a <i>color</i> tag and puts them
* in a map keyed by tag names.
*
* @param entry The <i>color</i> entry tag.
* @return The pairs <i>(tag-name, tag-value)</i> built from the tags
* contained within the <i>color</i> tag.
* @throws DOMException If the entry contents couldn't be retrieved.
* @throws ConfigException If the <i>font</i> tag is not structured as
* expected.
*/
private Map<String, String> extractValues(Node entry)
throws DOMException, ConfigException
{
Map<String, String> tags = new HashMap<String, String>();
if (entry.hasChildNodes()) {
NodeList children = entry.getChildNodes();
int n = children.getLength();
Node child;
while (0 < n) {
child = children.item(--n);
if (child.getNodeType() == Node.ELEMENT_NODE)
extractColorTag(child, tags);
}
}
if (tags.keySet().size() != 3)
throw new ConfigException("Missing tags within color tag.");
return tags;
}
//TODO: remove the checks (which are not complete anyway) and the
//ConfigException when we have an XML schema for config files.
/**
* Adds the given tag name and value to the passed map.
*
* @param tag A tag within the <i>color</i> tag.
* @param values The map containing the pairs
* <i>(tag-name, tag-value)</i> relative to the
* <i>color</i> tag that contains <code>tag</code>.
* @throws DOMException If the entry contents couldn't be retrieved.
* @throws ConfigException If <code>tag</code> is not one of the tags that
* we expect to be within an <i>font</i> tag.
*/
private void extractColorTag(Node tag, Map<String, String> values)
throws DOMException, ConfigException
{
String tagName = tag.getNodeName(),
tagValue = tag.getFirstChild().getNodeValue();
if (RED_TAG.equals(tagName) || GREEN_TAG.equals(tagName) ||
BLUE_TAG.equals(tagName)) {
values.put(tagName, tagValue);
return;
}
throw new ConfigException(
"Unrecognized tag within the color entry: "+tagName);
}
//TODO: remove the checks (which are not complete anyway) and the
//ConfigException when we have an XML schema for config files.
/** Creates a new instance. */
ColorEntry() {}
/**
* Returns a {@link Color} object, built from the configuration information.
*
* @return See above.
*/
Object getValue() { return value; }
/**
* Implemented as specified by {@link Entry}.
* @see Entry#setContent(Node)
* @throws ConfigException If the configuration entry couldn't be handled.
*/
protected void setContent(Node tag)
throws ConfigException
{
try {
Map<String, String> tags = extractValues(tag);
value = new Color(getRedComponent(tags), getGreenComponent(tags),
getBlueComponent(tags));
} catch (DOMException dex) {
rethrow("Can't parse font entry.", dex);
}
}
}