org.w3c.css.properties.aural.ACssVolume Maven / Gradle / Ivy
//
// $Id: ACssVolume.java,v 1.4 2010-01-05 13:49:37 ylafon Exp $
// From Philippe Le Hegaret ([email protected])
//
// (c) COPYRIGHT MIT and INRIA, 1997.
// Please first read the full copyright statement in file COPYRIGHT.html
package org.w3c.css.properties.aural;
import org.w3c.css.parser.CssStyle;
import org.w3c.css.properties.css.CssProperty;
import org.w3c.css.util.ApplContext;
import org.w3c.css.util.InvalidParamException;
import org.w3c.css.values.CssExpression;
import org.w3c.css.values.CssIdent;
import org.w3c.css.values.CssNumber;
import org.w3c.css.values.CssPercentage;
import org.w3c.css.values.CssValue;
/**
* 'volume'
*
*
* Value: <percentage> | silent | x-soft | soft | medium | loud | x-loud
* Initial: medium
* Applies to: all elements
* Inherited: yes
* Percentage values: relative to user-specified mapping
*
*
The legal range of percentage values is 0% to 100%. Note that '0%'
* does not mean the same as "silent". 0% represents the
* minimum audible volume level and 100% corresponds to the
* maximum comfortable level. There is a fixed mapping between
* keyword values and percentages:
*
*
* - 'silent' = no sound at all, the element is spoken silently
*
- 'x-soft' = '0%'
*
- 'soft' = '25%'
*
- 'medium' = '50%'
*
- 'loud' = '75%'
*
- 'x-loud' = '100%'
*
*
* Volume refers to the median volume of the waveform. In other words,
* a highly inflected voice at a volume of 50 might peak well above
* that. The overall values are likely to be human adjustable
* for comfort, for example with a physical volume control (which would
* increase both the 0% and 100% values proportionately); what this
* property does is adjust the dynamic range.
*
*
*
The UA should allow the values corresponding to 0% and
* 100% to be set by the listener. No one setting is universally
* applicable; suitable values depend on the equipment in use (speakers,
* headphones), the environment (in car, home theater, library) and
* personal preferences. Some examples:
*
*
- A browser for in-car use has a setting for when there is lots
* of background noise. 0% would map to a fairly high level and 100% to a
* quite high level. The speech is easily audible over the road noise but
* the overall dynamic range is compressed. Plusher cars with better
* insulation allow a wider dynamic range.
*
*
*
- Another speech browser is being used in the home, late at night,
* (don't annoy the neighbors) or in a shared study room. 0% is set to
* a very quiet level and 100% to a fairly quiet level, too. As with the first
* example, there is a low slope; the dynamic range is reduced. The
* actual volumes are low here, wheras they were high in the first
* example.
*
*
- In a quiet and isolated house, an expensive hi-fi home theatre
* setup. 0% is set fairly low and 100% to quite high; there is wide
* dynamic range.
*
*
* The same authors stylesheet could be used in all cases, simply by
* mapping the 0 and 100 points suitably at the client side.
*
*
If an element has a volume of silent, it is spoken silently. It
* takes up the same time as if it had been spoken, including any pause
* before and after the element, but no sound is generated. This may be
* used in language teaching applications, for example. A pause is
* gdenerated for the pupil to speak the element themselves. Note:
* the value is inherited so child elements will also be silent. Child
* elements may however set the volume to a non-silent value and will
* then be spoken.
*
*
To inhibit the speaking of an element and all it's children so that
* it takes no time at all (for example, to get the effect of collapsing
* and expanding lists) use the CSS1 property 'display'
*
*
display: none
*
* When using the rule display: none the element takes up
* no time; it is not represented as a pause the length of the
* spoken text.
*
* @version $Revision: 1.4 $
*/
public class ACssVolume extends ACssProperty {
CssValue value;
private static int[] hash_values;
private static String[] VOLUME = { "silent", "x-soft", "soft",
"medium", "loud", "x-loud" };
private static CssIdent defaultValue = new CssIdent(VOLUME[3]);
/**
* Create a new ACssVolume
*/
public ACssVolume() {
value = defaultValue;
}
/**
* Creates a new ACssVolume
* @param expression The expression for this property
* @exception InvalidParamException Values are incorrect
*/
public ACssVolume(ApplContext ac, CssExpression expression, boolean check)
throws InvalidParamException {
this();
if(check && expression.getCount() > 1) {
throw new InvalidParamException("unrecognize", ac);
}
CssValue val = expression.getValue();
//int index;
setByUser();
if (val.equals(inherit)) {
value = inherit;
} else if (val instanceof CssIdent) {
value = checkIdent(ac, (CssIdent) val);
} else if (val instanceof CssPercentage) {
value = val;
/*
can't do the clipping here. see specs
float v = ((Float) ((CssPercentage) val).get()).floatValue();
if (v < 0 || v > 100) {
// clipped
value = new CssPercentage((v<0)?0:100);
} else {
value = (CssPercentage) val;
}
*/
} else if (val instanceof CssNumber) {
CssNumber num = (CssNumber) val;
int i = (int) num.getValue();
if (i < 0) {
value = new CssNumber(ac, 0);
} else if (i > 100) {
value = new CssNumber(ac, 100);
} else {
value = val;
}
expression.next();
} else {
throw new InvalidParamException("value",
expression.getValue().toString(),
getPropertyName(), ac);
}
expression.next();
}
public ACssVolume(ApplContext ac, CssExpression expression)
throws InvalidParamException {
this(ac, expression, false);
}
/**
* Returns the value of this property
*/
public Object get() {
return value;
}
/**
* Returns true if this property is "softly" inherited
* e.g. his value is equals to inherit
*/
public boolean isSoftlyInherited() {
return value.equals(inherit);
}
/**
* Returns some usable value of this property...
*
* @deprecated
*/
public float getValue() { // vm
return ((CssNumber) value).getValue();
}
/**
* Returns the name of this property
*/
public String getPropertyName() {
return "volume";
}
/**
* Returns a string representation of the object.
*/
public String toString() {
return value.toString();
}
/**
* Add this property to the CssStyle.
*
* @param style The CssStyle
*/
public void addToStyle(ApplContext ac, CssStyle style) {
if (((ACssStyle) style).acssVolume != null)
style.addRedefinitionWarning(ac, this);
((ACssStyle) style).acssVolume = this;
}
/**
* Compares two properties for equality.
*
* @param property The other property.
*/
public boolean equals(CssProperty property) {
return (property instanceof ACssVolume &&
value.equals(((ACssVolume) property).value));
}
private CssIdent checkIdent(ApplContext ac, CssIdent ident)
throws InvalidParamException {
int hash = ident.hashCode();
for (int i = 0; i < VOLUME.length; i++) {
if (hash_values[i] == hash) {
return ident;
}
}
throw new InvalidParamException("value", ident.toString(),
getPropertyName(), ac);
}
/** @deprecated */
private CssPercentage ValueOfIdent(ApplContext ac, CssIdent ident)
throws InvalidParamException {
int hash = ident.hashCode();
for (int i = 0; i < VOLUME.length; i++) {
if (hash_values[i] == hash) {
return new CssPercentage(ACssProperties.getValue(this, VOLUME[i]));
}
}
throw new InvalidParamException("value", ident.toString(),
getPropertyName(), ac);
}
/**
* Get this property in the style.
*
* @param style The style where the property is
* @param resolve if true, resolve the style to find this property
*/
public CssProperty getPropertyInStyle(CssStyle style, boolean resolve) {
if (resolve) {
return ((ACssStyle) style).getVolume();
} else {
return ((ACssStyle) style).acssVolume;
}
}
static {
hash_values = new int[VOLUME.length];
for (int i = 0; i < VOLUME.length; i++)
hash_values[i] = VOLUME[i].hashCode();
}
}