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/*
* Copyright 2000,2005 wingS development team.
*
* This file is part of wingS (http://wingsframework.org).
*
* wingS is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1
* of the License, or (at your option) any later version.
*
* Please see COPYING for the complete licence.
*/
package org.wings.style;
import org.wings.Renderable;
import org.wings.io.Device;
import java.io.IOException;
import java.io.Serializable;
import java.util.*;
/**
* A straightforward implementation of CSSPropertySet using a hash map.
*
* @author Holger Engels
*/
public class CSSAttributeSet implements Renderable, Serializable, Cloneable {
/** Empty immutable attribute set. */
public static final CSSAttributeSet EMPTY_ATTRIBUTESET =
new CSSAttributeSet() {
private UnsupportedOperationException doThrow() {
return new UnsupportedOperationException("Cannot change values for the global EMPTY_ATTRIBUTESET. " +
"You attempted to modify this unmodifiable CSSPropertySet.");
}
public String put(String name, String value) {
throw doThrow();
}
@Override
public boolean putAll(CSSAttributeSet attributes) {
throw doThrow();
}
};
/** The map holding CSSProperty to String */
private HashMap map;
/** Cached String representation of this attribute set. */
private String cachedStringRepresentation;
/**
* create a CSSPropertySet from the given HashMap.
*/
private CSSAttributeSet(HashMap map) {
this.map = map;
}
/**
* Creates a new, empty atribute set.
*/
public CSSAttributeSet() {
}
public CSSAttributeSet(CSSProperty cssProperty, String cssPropertyValue) {
put(cssProperty, cssPropertyValue);
}
/**
* Creates a new attribute set based on a supplied set of attributes.
*
* @param source the set of attributes
*/
public CSSAttributeSet(CSSAttributeSet source) {
putAll(source);
}
/**
* Checks whether the set of attributes is empty.
*
* @return true if the set is empty else false
*/
public final boolean isEmpty() {
return map == null || map.isEmpty();
}
/**
* Gets a count of the number of attributes.
*
* @return the count
*/
public final int size() {
return map == null ? 0 : map.size();
}
public final void clear() {
if (map != null) {
map.clear();
}
}
/**
* Tells whether a given attribute is defined.
*
* @param name the attribute name
* @return true if the attribute is defined
*/
public final boolean contains(CSSProperty name) {
return map != null && map.containsKey(name);
}
/**
* Gets the Set of defined CSS property names.
*
* @return A set of {@link CSSProperty} for which this CSSAttributeSet contains a value.
*/
public final Map properties() {
if (map != null) {
return Collections.unmodifiableMap(map);
} else {
return Collections.emptyMap();
}
}
/**
* Gets the value of an css property.
*
* @param property the attribute property
* @return the value
*/
public final String get(CSSProperty property) {
return map == null ? null : (String) map.get(property);
}
/**
* Adds an attribute to the list.
*
* @param name the attribute name
* @param value the attribute value
*/
public String put(CSSProperty name, String value) {
cachedStringRepresentation = null;
if (map == null) {
map = new HashMap<>(8);
}
if (value == null)
return remove(name);
return (String) map.put(name, value);
}
/**
* Adds a set of attributes to the list.
*
* @param attributes the set of attributes to add
*/
public boolean putAll(CSSAttributeSet attributes) {
cachedStringRepresentation = null;
if (map == null)
map = new HashMap<>(8);
boolean changed = false;
for (Map.Entry entry1 : attributes.properties().entrySet()) {
Map.Entry entry = (Map.Entry) entry1;
CSSProperty property = (CSSProperty) entry.getKey();
changed = changed || (put(property, (String) entry.getValue()) != null);
}
return changed;
}
/**
* Removes an attribute from the list.
*
* @param name the attribute name
* @return The previous value for this CSS property
*/
public String remove(CSSProperty name) {
cachedStringRepresentation = null;
return map == null ? null : (String) map.remove(name);
}
// --- Object methods ---------------------------------
/**
* Clones a set of attributes.
*
* @return the new set of attributes
*/
@Override
public Object clone() {
if (isEmpty()) {
return new CSSAttributeSet();
} else {
return new CSSAttributeSet((HashMap) map.clone());
}
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
final CSSAttributeSet that = (CSSAttributeSet)o;
return !(map != null ? !map.equals(that.map) : that.map != null);
}
@Override
public int hashCode() {
return (map != null ? map.hashCode() : 0);
}
// /**
// * Write style definition to the device. If include is true, write those
// * contained in the {@link java.util.List}. If include is false, write those not contained
// * in the {@link java.util.List}.
// * Basically this is a filter on the styles, so we can separate styles for
// * one logical component onto multiple real html elements.
// */
// private static void writeFiltered(Device d, Map map, Set l, boolean include) throws IOException {
// if (l == null) l = Collections.EMPTY_SET;
// if (map != null) {
// Iterator names = map.entrySet().iterator();
// while (names.hasNext()) {
// Map.Entry next = (Map.Entry) names.next();
// if ( !(l.contains(next.getKey()) ^ include) ) {
// d.print(next.getKey()).print(':')
// .print(next.getValue())
// .print(';');
// }
// }
// }
// }
//
// /**
// * Write style definition to the device. Write only those not contained
// * in the set.
// */
// public static void writeExcluding(Device d, Map map, Set l) throws IOException {
// writeFiltered(d, map, l, false);
// }
//
// /**
// * Write style definition to the device. Write only those contained
// * in the set.
// */
// public static void writeIncluding(Device d, Map map, Set l) throws IOException {
// writeFiltered(d, map, l, true);
// }
/**
* Write style definition to the device
*/
@Override
public void write(Device d)
throws IOException {
d.print(toString());
}
/**
* Converts the attribute set to a String.
*
* @return the string
*/
@Override
public String toString() {
if (cachedStringRepresentation == null) {
final StringBuilder builder = new StringBuilder();
if (map != null) {
for (Map.Entry entry : map.entrySet()) {
builder.append(entry.getKey());
builder.append(':');
builder.append(entry.getValue());
builder.append(';');
}
}
cachedStringRepresentation = builder.toString();
}
return cachedStringRepresentation;
}
}