/*******************************************************************************
* Copyright (c) 2000, 2011 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.custom;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.internal.CloneableCompatibility;
/**
* <code>StyleRange</code> defines a set of styles for a specified
* range of text.
* <p>
* The hashCode() method in this class uses the values of the public
* fields to compute the hash value. When storing instances of the
* class in hashed collections, do not modify these fields after the
* object has been inserted.
* </p>
*
* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
*/
public class StyleRange extends TextStyle implements CloneableCompatibility {
/**
* the start offset of the range, zero-based from the document start
*/
public int start;
/**
* the length of the range
*/
public int length;
/**
* the font style of the range. It may be a combination of
* SWT.NORMAL, SWT.ITALIC or SWT.BOLD
*
* Note: the font style is not used if the <code>font</code> attribute
* is set
*/
public int fontStyle = SWT.NORMAL;
/**
* Create a new style range with no styles
*
* @since 3.2
*/
public StyleRange() {
}
/**
* Create a new style range from an existing text style.
*
* @param style the text style to copy
*
* @since 3.4
*/
public StyleRange(TextStyle style) {
super(style);
}
/**
* Create a new style range.
*
* @param start start offset of the style
* @param length length of the style
* @param foreground foreground color of the style, null if none
* @param background background color of the style, null if none
*/
public StyleRange(int start, int length, Color foreground, Color background) {
super(null, foreground, background);
this.start = start;
this.length = length;
}
/**
* Create a new style range.
*
* @param start start offset of the style
* @param length length of the style
* @param foreground foreground color of the style, null if none
* @param background background color of the style, null if none
* @param fontStyle font style of the style, may be SWT.NORMAL, SWT.ITALIC or SWT.BOLD
*/
public StyleRange(int start, int length, Color foreground, Color background, int fontStyle) {
this(start, length, foreground, background);
this.fontStyle = fontStyle;
}
/**
* Compares the argument to the receiver, and returns true
* if they represent the <em>same</em> object using a class
* specific comparison.
*
* @param object the object to compare with this object
* @return <code>true</code> if the object is the same as this object and <code>false</code> otherwise
*
* @see #hashCode()
*/
@Override
public boolean equals(Object object) {
if (object == this) return true;
if (object instanceof StyleRange) {
StyleRange style = (StyleRange)object;
if (start != style.start) return false;
if (length != style.length) return false;
return similarTo(style);
}
return false;
}
/**
* Returns an integer hash code for the receiver. Any two
* objects that return <code>true</code> when passed to
* <code>equals</code> must return the same value for this
* method.
*
* @return the receiver's hash
*
* @see #equals(Object)
*/
@Override
public int hashCode() {
return super.hashCode() ^ fontStyle;
}
boolean isVariableHeight() {
return font != null || metrics != null || rise != 0;
}
/**
* Returns whether or not the receiver is unstyled (i.e., does not have any
* style attributes specified).
*
* @return true if the receiver is unstyled, false otherwise.
*/
public boolean isUnstyled() {
if (font != null) return false;
if (rise != 0) return false;
if (metrics != null) return false;
if (foreground != null) return false;
if (background != null) return false;
if (fontStyle != SWT.NORMAL) return false;
if (underline) return false;
if (strikeout) return false;
if (borderStyle != SWT.NONE) return false;
return true;
}
/**
* Compares the specified object to this StyleRange and answer if the two
* are similar. The object must be an instance of StyleRange and have the
* same field values for except for start and length.
*
* @param style the object to compare with this object
* @return true if the objects are similar, false otherwise
*/
public boolean similarTo(StyleRange style) {
if (!super.equals(style)) return false;
if (fontStyle != style.fontStyle) return false;
return true;
}
/**
* Returns a new StyleRange with the same values as this StyleRange.
*
* @return a shallow copy of this StyleRange
*/
@Override
public Object clone() {
try {
return super.clone();
} catch (CloneNotSupportedException e) {
return null;
}
}
/**
* Returns a string containing a concise, human-readable
* description of the receiver.
*
* @return a string representation of the StyleRange
*/
@Override
public String toString() {
StringBuffer buffer = new StringBuffer();
buffer.append("StyleRange {");
buffer.append(start);
buffer.append(", ");
buffer.append(length);
buffer.append(", fontStyle=");
switch (fontStyle) {
case SWT.BOLD:
buffer.append("bold");
break;
case SWT.ITALIC:
buffer.append("italic");
break;
case SWT.BOLD | SWT.ITALIC:
buffer.append("bold-italic");
break;
default:
buffer.append("normal");
}
String str = super.toString();
int index = str.indexOf('{');
str = str.substring(index + 1);
if (str.length() > 1) buffer.append(", ");
buffer.append(str);
return buffer.toString();
}
}