/*
* Copyright (c) 1998, 2003, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package javax.swing.text;
import java.io.Serializable;
/**
* A TabSet is comprised of many TabStops. It offers methods for locating the
* closest TabStop to a given position and finding all the potential TabStops.
* It is also immutable.
* <p>
* <strong>Warning:</strong>
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeans<sup><font size="-2">TM</font></sup>
* has been added to the <code>java.beans</code> package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author Scott Violet
*/
public class TabSet implements Serializable
{
/** TabStops this TabSet contains. */
private TabStop[] tabs;
/**
* Since this class is immutable the hash code could be
* calculated once. MAX_VALUE means that it was not initialized
* yet. Hash code shouldn't has MAX_VALUE value.
*/
private int hashCode = Integer.MAX_VALUE;
/**
* Creates and returns an instance of TabSet. The array of Tabs
* passed in must be sorted in ascending order.
*/
public TabSet(TabStop[] tabs) {
// PENDING(sky): If this becomes a problem, make it sort.
if(tabs != null) {
int tabCount = tabs.length;
this.tabs = new TabStop[tabCount];
System.arraycopy(tabs, 0, this.tabs, 0, tabCount);
}
else
this.tabs = null;
}
/**
* Returns the number of Tab instances the receiver contains.
*/
public int getTabCount() {
return (tabs == null) ? 0 : tabs.length;
}
/**
* Returns the TabStop at index <code>index</code>. This will throw an
* IllegalArgumentException if <code>index</code> is outside the range
* of tabs.
*/
public TabStop getTab(int index) {
int numTabs = getTabCount();
if(index < 0 || index >= numTabs)
throw new IllegalArgumentException(index +
" is outside the range of tabs");
return tabs[index];
}
/**
* Returns the Tab instance after <code>location</code>. This will
* return null if there are no tabs after <code>location</code>.
*/
public TabStop getTabAfter(float location) {
int index = getTabIndexAfter(location);
return (index == -1) ? null : tabs[index];
}
/**
* @return the index of the TabStop <code>tab</code>, or -1 if
* <code>tab</code> is not contained in the receiver.
*/
public int getTabIndex(TabStop tab) {
for(int counter = getTabCount() - 1; counter >= 0; counter--)
// should this use .equals?
if(getTab(counter) == tab)
return counter;
return -1;
}
/**
* Returns the index of the Tab to be used after <code>location</code>.
* This will return -1 if there are no tabs after <code>location</code>.
*/
public int getTabIndexAfter(float location) {
int current, min, max;
min = 0;
max = getTabCount();
while(min != max) {
current = (max - min) / 2 + min;
if(location > tabs[current].getPosition()) {
if(min == current)
min = max;
else
min = current;
}
else {
if(current == 0 || location > tabs[current - 1].getPosition())
return current;
max = current;
}
}
// no tabs after the passed in location.
return -1;
}
/**
* Indicates whether this <code>TabSet</code> is equal to another one.
* @param o the <code>TabSet</code> instance which this instance
* should be compared to.
* @return <code>true</code> if <code>o</code> is the instance of
* <code>TabSet</code>, has the same number of <code>TabStop</code>s
* and they are all equal, <code>false</code> otherwise.
*
* @since 1.5
*/
public boolean equals(Object o) {
if (o == this) {
return true;
}
if (o instanceof TabSet) {
TabSet ts = (TabSet) o;
int count = getTabCount();
if (ts.getTabCount() != count) {
return false;
}
for (int i=0; i < count; i++) {
TabStop ts1 = getTab(i);
TabStop ts2 = ts.getTab(i);
if ((ts1 == null && ts2 != null) ||
(ts1 != null && !getTab(i).equals(ts.getTab(i)))) {
return false;
}
}
return true;
}
return false;
}
/**
* Returns a hashcode for this set of TabStops.
* @return a hashcode value for this set of TabStops.
*
* @since 1.5
*/
public int hashCode() {
if (hashCode == Integer.MAX_VALUE) {
hashCode = 0;
int len = getTabCount();
for (int i = 0; i < len; i++) {
TabStop ts = getTab(i);
hashCode ^= ts != null ? getTab(i).hashCode() : 0;
}
if (hashCode == Integer.MAX_VALUE) {
hashCode -= 1;
}
}
return hashCode;
}
/**
* Returns the string representation of the set of tabs.
*/
public String toString() {
int tabCount = getTabCount();
StringBuffer buffer = new StringBuffer("[ ");
for(int counter = 0; counter < tabCount; counter++) {
if(counter > 0)
buffer.append(" - ");
buffer.append(getTab(counter).toString());
}
buffer.append(" ]");
return buffer.toString();
}
}