/*
* NOTE: This copyright does *not* cover user programs that use HQ
* program services by normal system calls through the application
* program interfaces provided as part of the Hyperic Plug-in Development
* Kit or the Hyperic Client Development Kit - this is merely considered
* normal use of the program, and does *not* fall under the heading of
* "derived work".
*
* Copyright (C) [2004, 2005, 2006], Hyperic, Inc.
* This file is part of HQ.
*
* HQ is free software; you can redistribute it and/or modify
* it under the terms version 2 of the GNU General Public License as
* published by the Free Software Foundation. This program 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 for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA.
*/
package org.hyperic.util.pager;
import java.io.Serializable;
/**
* A utility class to wrap up all the paging/sorting options that
* are frequently used with finders and other methods that return
* lists of things.
*/
public class PageControl implements Serializable, Cloneable {
public static final int SIZE_UNLIMITED = -1;
public static final int SORT_UNSORTED = 0;
public static final int SORT_ASC = 1;
public static final int SORT_DESC = 2;
/** The SQL string representation of the above sort constants
Note that the indices into this array line up with the
constant values above for the SORT_XXX constants. */
public static final String[] SQL_SORTS =
{ "", "ASC", "DESC" };
public static final PageControl PAGE_ALL
= new PageControl(0, SIZE_UNLIMITED, true);
public static final PageControl PAGE_NONE
= new PageControl(0, 0, true);
public static final PageControl PAGE_MIN
= new PageControl(0, 1, true);
private int _pagenum = 0;
private int _pagesize = SIZE_UNLIMITED;
private int _sortorder = SORT_UNSORTED;
private int _sortattribute = SortAttribute.DEFAULT;
private boolean _immutable = false;
private Serializable metaData; // Meta-data that PageLists have returned
private PageControl (int pagenum, int pagesize, boolean immutable) {
this(pagenum, pagesize);
_immutable = immutable;
}
public PageControl () {}
public PageControl (int pagenum, int pagesize) {
_pagenum = pagenum;
_pagesize = pagesize;
}
public PageControl (int pagenum, int pagesize,
int sortorder, int sortattribute) {
_pagenum = pagenum;
_pagesize = pagesize;
_sortorder = sortorder;
_sortattribute = sortattribute;
}
public PageControl (PageControl pc) {
_pagenum = pc.getPagenum();
_pagesize = pc.getPagesize();
_sortorder = pc.getSortorder();
_sortattribute = pc.getSortattribute();
metaData = pc.getMetaData();
}
public boolean isAscending () { return _sortorder == SORT_ASC; }
public boolean isDescending () { return _sortorder == SORT_DESC; }
/**
* sets the initial defaults for the PageControl. Sort attribute specifies
* which attribute to sort on.
*
* @param pc
* @param defaultSortAttr specifies the attribute to sort on.
* @return PageControl
*/
public static PageControl initDefaults ( PageControl pc,
int defaultSortAttr ) {
if (pc == null) {
pc = new PageControl();
}
else {
pc = (PageControl) pc.clone();
}
if (pc.getSortattribute() == SortAttribute.DEFAULT) {
pc.setSortattribute(defaultSortAttr);
}
if (pc.getSortorder() == SORT_UNSORTED) {
pc.setSortorder(SORT_ASC);
}
return pc;
}
/** @return The current page number (0-based) */
public int getPagenum () { return _pagenum; }
/** @param pagenum Set the current page number to <code>pagenum</code> */
public void setPagenum (int pagenum) {
if (_immutable) throw new IllegalStateException("immutable object");
_pagenum = pagenum;
}
/** @return The current page size */
public int getPagesize () { return _pagesize; }
/** @param pagesize Set the current page size to this value */
public void setPagesize (int pagesize) {
if (_immutable) throw new IllegalStateException("immutable object");
_pagesize = pagesize;
}
/** @return The sort order used. This is one of the SORT_XXX constants. */
public int getSortorder () { return _sortorder; }
/** @param sortorder Sort order to use, one of the SORT_XXX constants. */
public void setSortorder (int sortorder) {
if (_immutable) throw new IllegalStateException("immutable object");
_sortorder = sortorder;
}
/** @return The attribute that the sort is based on. */
public int getSortattribute () { return _sortattribute; }
/** @param attr Set the attribute that the sort is based on. */
public void setSortattribute (int attr) {
if (_immutable) throw new IllegalStateException("immutable object");
_sortattribute = attr;
}
public Serializable getMetaData() { return this.metaData; }
public void setMetaData(Serializable metaData) {
if (_immutable) throw new IllegalStateException("immutable object");
this.metaData = metaData;
}
/**
* Get the index of the first item on the page as dictated by the
* page size and page number.
*/
public int getPageEntityIndex(){
return _pagenum * _pagesize;
}
public String toString() {
// shortcuts for common cases
if (this == PageControl.PAGE_ALL) return "{ALL}";
if (this == PageControl.PAGE_NONE) return "{NONE}";
if (this.equals(PageControl.PAGE_ALL)) return "{ALL}";
if (this.equals(PageControl.PAGE_NONE)) return "{NONE}";
StringBuffer s = new StringBuffer("{");
s.append("pn=" + _pagenum + " ");
s.append("ps=" + _pagesize + " ");
s.append("so=");
switch(_sortorder) {
case SORT_ASC:
s.append("asc ");
break;
case SORT_DESC:
s.append("desc");
break;
case SORT_UNSORTED:
s.append("unsorted ");
break;
default:
s.append(' ');
}
s.append("sa=" + _sortattribute + " ");
s.append("}");
return s.toString();
}
public boolean equals ( Object o ) {
if ( o instanceof PageControl ) {
PageControl pc = (PageControl) o;
return _pagenum == pc.getPagenum()
&& _pagesize == pc.getPagesize()
&& _sortorder == pc.getSortorder()
&& _sortattribute == pc.getSortattribute();
}
return false;
}
public int hashCode () {
return (37*_pagenum)
+ (37*_pagesize)
+ (37*_sortorder)
+ (37*_sortattribute);
}
public Object clone(){
PageControl res = new PageControl(_pagenum, _pagesize, _sortorder,
_sortattribute);
res.metaData = metaData;
return res;
}
}