/*
* 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.app;
import java.io.Serializable;
import java.util.Iterator;
import java.util.SortedMap;
import java.util.TreeMap;
/**
* A <code>Style</code> implementation which may be modified.
* Note that modifications to the <code>Style</code> will not necessarily be
* reflected in <code>Component</code>s that use the <code>Style</code>
* unless the <code>Component</code>s are specifically informed of the changes,
* i.e., by resetting the shared style of a <code>Component</code>.
* As such, shared <code>Style</code>s should not be updated once they are
* in use by <code>Component</code>s, as it will result in undefined behavior.
*/
public class MutableStyle
implements Style {
private static final int GROW_RATE = 5 * 2; // Must be a multiple of 2.
private static final Object[] EMPTY = new Object[0];
/**
* An <code>Iterator</code> which returns the names of properties which
* are set in the style.
*/
private class PropertyNameIterator
implements Iterator {
private int index = 0;
/**
* @see java.util.Iterator#hasNext()
*/
public boolean hasNext() {
return index < length;
}
/**
* @see java.util.Iterator#next()
*/
public Object next() {
Object value = data[index];
index += 2;
return value;
}
/**
* @see java.util.Iterator#remove()
*/
public void remove() {
throw new UnsupportedOperationException();
}
}
/**
* A value object which stores the indexed values of a property.
*/
public class IndexedPropertyValue
implements Serializable {
private SortedMap indicesToValues;
/**
* Returns the value at the specified index.
*
* @param index the index
* @return the value
*/
public Object getValue(int index) {
if (indicesToValues == null) {
return null;
} else {
return indicesToValues.get(new Integer(index));
}
}
/**
* Returns the set property indices as an
* <code>Integer</code>-returning <code>Iterator</code>.
*
* @return an iterator over the indices
*/
public Iterator getIndices() {
return indicesToValues.keySet().iterator();
}
/**
* Determines if a value is set at the specified index.
*
* @param index the index
* @return true if a value is set
*/
public boolean hasValue(int index) {
return indicesToValues != null && indicesToValues.containsKey(new Integer(index));
}
/**
* Removes the value at the specified index.
*
* @param index the index
*/
private void removeValue(int index) {
if (indicesToValues != null) {
indicesToValues.remove(new Integer(index));
if (indicesToValues.size() == 0) {
indicesToValues = null;
}
}
}
/**
* Sets the value at the specified index.
*
* @param index the index
* @param value the new property value
*/
private void setValue(int index, Object value) {
if (indicesToValues == null) {
indicesToValues = new TreeMap();
}
indicesToValues.put(new Integer(index), value);
}
}
private Object[] data = EMPTY;
int length = 0; // Number of items * 2;
/**
* Default constructor.
*/
public MutableStyle() {
super();
}
/**
* Adds the content of the specified style to this style.
*
* @param style the style to add
*/
public void addStyleContent(Style style) {
Iterator nameIt = style.getPropertyNames();
while (nameIt.hasNext()) {
String name = (String) nameIt.next();
Object value = style.getProperty(name);
if (value instanceof IndexedPropertyValue) {
IndexedPropertyValue indexedPropertyValue = (IndexedPropertyValue) value;
Iterator indexIt = indexedPropertyValue.getIndices();
while (indexIt.hasNext()) {
int index = ((Integer) indexIt.next()).intValue();
setIndexedProperty(name, index, indexedPropertyValue.getValue(index));
}
} else {
setProperty(name, value);
}
}
}
/**
* @see nextapp.echo2.app.Style#getIndexedProperty(java.lang.String, int)
*/
public Object getIndexedProperty(String propertyName, int propertyIndex) {
Object value = retrieveProperty(propertyName);
if (!(value instanceof IndexedPropertyValue)) {
return null;
}
return ((IndexedPropertyValue) value).getValue(propertyIndex);
}
/**
* @see nextapp.echo2.app.Style#getProperty(java.lang.String)
*/
public Object getProperty(String propertyName) {
return retrieveProperty(propertyName);
}
/**
* @see nextapp.echo2.app.Style#getPropertyIndices(java.lang.String)
*/
public Iterator getPropertyIndices(String propertyName) {
Object value = getProperty(propertyName);
if (!(value instanceof IndexedPropertyValue)) {
return null;
}
return ((IndexedPropertyValue) value).getIndices();
}
/**
* @see nextapp.echo2.app.Style#getPropertyNames()
*/
public Iterator getPropertyNames() {
return new PropertyNameIterator();
}
/**
* @see nextapp.echo2.app.Style#isIndexedPropertySet(java.lang.String, int)
*/
public boolean isIndexedPropertySet(String propertyName, int index) {
Object value = retrieveProperty(propertyName);
if (!(value instanceof IndexedPropertyValue)) {
return false;
}
return ((IndexedPropertyValue) value).hasValue(index);
}
/**
* @see nextapp.echo2.app.Style#isPropertySet(java.lang.String)
*/
public boolean isPropertySet(String propertyName) {
int propertyNameHashCode = propertyName.hashCode();
for (int i = 0; i < length; i += 2) {
if (propertyNameHashCode == data[i].hashCode() && propertyName.equals(data[i])) {
return true;
}
}
return false;
}
/**
* Removes a value of an indexed property from the <code>Style</code>.
*
* @param propertyName the name of the property
* @param propertyIndex the index of the property to remove
*/
public void removeIndexedProperty(String propertyName, int propertyIndex) {
Object value = retrieveProperty(propertyName);
if (!(value instanceof IndexedPropertyValue)) {
return;
}
((IndexedPropertyValue) value).removeValue(propertyIndex);
}
/**
* Removes a property from the <code>Style</code>.
*
* @param propertyName the name of the property to remove
*/
public void removeProperty(String propertyName) {
int propertyNameHashCode = propertyName.hashCode();
for (int i = 0; i < length; i += 2) {
if (propertyNameHashCode == data[i].hashCode() && propertyName.equals(data[i])) {
data[i] = data[length - 2];
data[i + 1] = data[length - 1];
data[length - 2] = null;
data[length - 1] = null;
length -= 2;
break;
}
}
if (length == 0) {
data = EMPTY;
}
}
/**
* Retrieves locally stored value of property.
*
* @param propertyName the name of the property
* @return the value of the property
*/
private Object retrieveProperty(String propertyName) {
int propertyNameHashCode = propertyName.hashCode();
for (int i = 0; i < length; i += 2) {
if (propertyNameHashCode == data[i].hashCode() && propertyName.equals(data[i])) {
return data[i + 1];
}
}
return null;
}
/**
* Sets an indexed property of the <code>Style</code>
*
* @param propertyName the name of the property
* @param propertyIndex the index of the property
* @param propertyValue the value of the property
*/
public void setIndexedProperty(String propertyName, int propertyIndex, Object propertyValue) {
Object value = retrieveProperty(propertyName);
if (!(value instanceof IndexedPropertyValue)) {
value = new IndexedPropertyValue();
setProperty(propertyName, value);
}
((IndexedPropertyValue) value).setValue(propertyIndex, propertyValue);
}
/**
* Sets a property of the <code>Style</code>.
* If <code>propertyValue</code> is null, the property will be
* removed.
*
* @param propertyName the name of the property
* @param propertyValue the value of the property
*/
public void setProperty(String propertyName, Object propertyValue) {
if (propertyValue == null) {
removeProperty(propertyName);
return;
}
if (data == EMPTY) {
data = new Object[GROW_RATE];
}
int propertyNameHashCode = propertyName.hashCode();
for (int i = 0; i < data.length; i += 2) {
if (data[i] == null) {
// Property is not set, space remains to set property.
// Add property at end.
data[i] = propertyName;
data[i + 1] = propertyValue;
length += 2;
return;
}
if (propertyNameHashCode == data[i].hashCode() && propertyName.equals(data[i])) {
// Found property, overwrite.
data[i + 1] = propertyValue;
return;
}
}
// Array is full: grow array.
Object[] newData = new Object[data.length + GROW_RATE];
System.arraycopy(data, 0, newData, 0, data.length);
newData[data.length] = propertyName;
newData[data.length + 1] = propertyValue;
length += 2;
data = newData;
}
/**
* Returns the number of properties set.
*
* @return the number of properties set
*/
public int size() {
return length / 2;
}
/**
* Returns a debug representation.
*
* @see java.lang.Object#toString()
*/
public String toString() {
StringBuffer out = new StringBuffer("MutableStyle {");
for (int i = 0; i < length; i += 2) {
out.append(data[i]);
out.append("=");
out.append(data[i + 1]);
if (i < length - 2) {
out.append(", ");
}
}
out.append("}");
return out.toString();
}
}