/usr/share/doc/libjosql-java/api/org/josql/utils/JoSQLComparator.html is in libjosql-java-doc 2.2-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<!--NewPage-->
<HTML>
<HEAD>
<!-- Generated by javadoc (build 1.6.0_22) on Thu Jun 30 09:42:04 UTC 2011 -->
<TITLE>
JoSQLComparator (JoSQL 2.2 - SQL for Java Objects)
</TITLE>
<META NAME="date" CONTENT="2011-06-30">
<LINK REL ="stylesheet" TYPE="text/css" HREF="../../../javadocsStyle.css" TITLE="Style">
<SCRIPT type="text/javascript">
function windowTitle()
{
if (location.href.indexOf('is-external=true') == -1) {
parent.document.title="JoSQLComparator (JoSQL 2.2 - SQL for Java Objects)";
}
}
</SCRIPT>
<NOSCRIPT>
</NOSCRIPT>
</HEAD>
<BODY BGCOLOR="white" onload="windowTitle();">
<HR>
<!-- ========= START OF TOP NAVBAR ======= -->
<A NAME="navbar_top"><!-- --></A>
<A HREF="#skip-navbar_top" title="Skip navigation links"></A>
<TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY="">
<TR>
<TD COLSPAN=2 BGCOLOR="#EEEEFF" CLASS="NavBarCell1">
<A NAME="navbar_top_firstrow"><!-- --></A>
<TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3" SUMMARY="">
<TR ALIGN="center" VALIGN="top">
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-summary.html"><FONT CLASS="NavBarFont1"><B>Package</B></FONT></A> </TD>
<TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> <FONT CLASS="NavBarFont1Rev"><B>Class</B></FONT> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="class-use/JoSQLComparator.html"><FONT CLASS="NavBarFont1"><B>Use</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../index-files/index-1.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A> </TD>
</TR>
</TABLE>
</TD>
<TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM>
</EM>
</TD>
</TR>
<TR>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
<A HREF="../../../org/josql/utils/ExpressionEvaluator.html" title="class in org.josql.utils"><B>PREV CLASS</B></A>
NEXT CLASS</FONT></TD>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
<A HREF="../../../index.html?org/josql/utils/JoSQLComparator.html" target="_top"><B>FRAMES</B></A>
<A HREF="JoSQLComparator.html" target="_top"><B>NO FRAMES</B></A>
<SCRIPT type="text/javascript">
<!--
if(window==top) {
document.writeln('<A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>');
}
//-->
</SCRIPT>
<NOSCRIPT>
<A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>
</NOSCRIPT>
</FONT></TD>
</TR>
<TR>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
SUMMARY: NESTED | FIELD | <A HREF="#constructor_summary">CONSTR</A> | <A HREF="#method_summary">METHOD</A></FONT></TD>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
DETAIL: FIELD | <A HREF="#constructor_detail">CONSTR</A> | <A HREF="#method_detail">METHOD</A></FONT></TD>
</TR>
</TABLE>
<A NAME="skip-navbar_top"></A>
<!-- ========= END OF TOP NAVBAR ========= -->
<HR>
<!-- ======== START OF CLASS DATA ======== -->
<H2>
<FONT SIZE="-1">
org.josql.utils</FONT>
<BR>
Class JoSQLComparator</H2>
<PRE>
<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</A>
<IMG SRC="../../../resources/inherit.gif" ALT="extended by "><B>org.josql.utils.JoSQLComparator</B>
</PRE>
<DL>
<DT><B>All Implemented Interfaces:</B> <DD><A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true" title="class or interface in java.util">Comparator</A></DD>
</DL>
<HR>
<DL>
<DT><PRE>public class <B>JoSQLComparator</B><DT>extends <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A><DT>implements <A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true" title="class or interface in java.util">Comparator</A></DL>
</PRE>
<P>
This class allows the ORDER BY clause of a JoSQL SQL clause to be used
as a Comparator. It should be noted that is the same as performing: <A HREF="../../../org/josql/Query.html#execute(java.util.List)"><CODE>Query.execute(List)</CODE></A>
but there are times when having a separate comparator is desirable.
The EXECUTE ON ALL clause is supported but you must call: <A HREF="../../../org/josql/utils/JoSQLComparator.html#doExecuteOn(java.util.List)"><CODE>doExecuteOn(List)</CODE></A>
first to ensure that they are executed.
<p>
This class is basically just a thin wrapper around using the comparator gained by
calling: <A HREF="../../../org/josql/Query.html#getOrderByComparator()"><CODE>Query.getOrderByComparator()</CODE></A>.
<p>
A note on performance, for small numbers of objects (around 1000) this comparator
has (for vanilla accessors, no function calls) pretty comparable performance against a
hand-coded Java Comparator that performs the same function. However start to scale the
numbers of objects and performance degrades, in testing for ~34000 FileWrapper objects
to order by: <code>path DESC, lastModified, name, length</code> took around: 1300ms.
The hand-coded Java Comparator took around: 180ms! The upshot is, if you need flexibility
and do not need to order large numbers of objects then use this kind of Comparator, if
performance and numbers of objects is an issue then hand-rolling your own Comparator
is probably best. As a side-note, to perform the following order by:
<code>lower(path) DESC, lastModified, name, length</code> using a JoSQLComparator took:
about: 1400ms. However modifying the hand-coded Comparator to use:
<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/String.html?is-external=true#compareToIgnoreCase(java.lang.String)" title="class or interface in java.lang"><CODE>String.compareToIgnoreCase(String)</CODE></A> then took about 860ms! And if you using:
<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/String.html?is-external=true#toLowerCase()" title="class or interface in java.lang"><CODE>String.toLowerCase()</CODE></A> for each string instead, it then takes about: 1800ms!
(Meaning that in certain circumstances JoSQL can be faster!)
<p>
<h3>Caching</h3>
<p>
It is not uncommon for a Comparator (even using the effecient merge-sort implementation of
<A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Collections.html?is-external=true#sort(java.util.List, java.util.Comparator)" title="class or interface in java.util"><CODE>Collections.sort(List,Comparator)</CODE></A>) to perform thousands (even millions!)
of comparisons.<br /><br />
However since JoSQL does not automatically cache the results of calls to functions and
results of accessor accesses the performance of this kind of "dynamic" Comparator can
quickly degrade. To mitigate this it is possible to turn "caching" on whereby the
Comparator will "remember" the results of the functions on a per object basis and use those
values instead of calling them again. This is not without it's downside however.
Firstly since a reference to the object will be held it is important (if caching is used
that you call: <A HREF="../../../org/josql/utils/JoSQLComparator.html#clearCache()"><CODE>clearCache()</CODE></A> once the Comparator has been used to free up those
references (it was considered using a <A HREF="/usr/share/doc/default-jdk-doc/api/java/util/WeakHashMap.html?is-external=true" title="class or interface in java.util"><CODE>WeakHashMap</CODE></A> but that doesn't provide
exactly what's needed here).<br /><br />
It is recommended that caching is turned on when the Comparator is to be used in a sort
operation , i.e. calling: <A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Collections.html?is-external=true#sort(java.util.List, java.util.Comparator)" title="class or interface in java.util"><CODE>Collections.sort(List,Comparator)</CODE></A> or similar
(however careful consideration needs to be given to the amount of memory that this
may consume, i.e. 4 bytes = 1 object reference, plus 1 List, plus 4 bytes per order
by "column" it soon adds up)<br /><br />
If the comparator is to be used in a <A HREF="/usr/share/doc/default-jdk-doc/api/java/util/TreeMap.html?is-external=true" title="class or interface in java.util"><CODE>TreeMap</CODE></A> or <A HREF="/usr/share/doc/default-jdk-doc/api/java/util/TreeSet.html?is-external=true" title="class or interface in java.util"><CODE>TreeSet</CODE></A>
then caching should not be used since the values may (and perhaps should) change over time
but due to caching the order won't change.
<P>
<P>
<HR>
<P>
<!-- ======== CONSTRUCTOR SUMMARY ======== -->
<A NAME="constructor_summary"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
<B>Constructor Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#JoSQLComparator(org.josql.Query)">JoSQLComparator</A></B>(<A HREF="../../../org/josql/Query.html" title="class in org.josql">Query</A> q)</CODE>
<BR>
Init this file filter with the query already built and parsed.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#JoSQLComparator(java.lang.String)">JoSQLComparator</A></B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A> q)</CODE>
<BR>
Init this filter with the query.</TD>
</TR>
</TABLE>
<!-- ========== METHOD SUMMARY =========== -->
<A NAME="method_summary"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
<B>Method Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#clearCache()">clearCache</A></B>()</CODE>
<BR>
Clear the cache, it is VITAL that you call this method before you use
the comparator (if it has been used before) otherwise data objects will
be "left around" and preventing the GC from cleaning them up.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> int</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#compare(java.lang.Object, java.lang.Object)">compare</A></B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> o1,
<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> o2)</CODE>
<BR>
Compares the objects as according to the ORDER BY clause.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#doExecuteOn(java.util.List)">doExecuteOn</A></B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</A> l)</CODE>
<BR>
Execute the EXECUTE ON ALL expressions.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Exception.html?is-external=true" title="class or interface in java.lang">Exception</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#getException()">getException</A></B>()</CODE>
<BR>
The <A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true#compare(T, T)" title="class or interface in java.util"><CODE>Comparator.compare(Object,Object)</CODE></A> method does not allow for
any exceptions to be thrown however since the execution of the ORDER BY clause
on the objects can cause the throwing of a <A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql"><CODE>QueryParseException</CODE></A> it should
be captured.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../org/josql/Query.html" title="class in org.josql">Query</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#getQuery()">getQuery</A></B>()</CODE>
<BR>
Get the Query we are using to process objects.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#isCaching()">isCaching</A></B>()</CODE>
<BR>
Return whether this comparator uses caching to improve performance.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#setCaching(boolean)">setCaching</A></B>(boolean b)</CODE>
<BR>
Set whether the comparator should use caching to improve performance.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#setQuery(org.josql.Query)">setQuery</A></B>(<A HREF="../../../org/josql/Query.html" title="class in org.josql">Query</A> q)</CODE>
<BR>
Set a new Query object for use in this filter.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/josql/utils/JoSQLComparator.html#setQuery(java.lang.String)">setQuery</A></B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A> q)</CODE>
<BR>
Set a new Query (string form) for use in this filter.</TD>
</TR>
</TABLE>
<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from class java.lang.<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#clone()" title="class or interface in java.lang">clone</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#notify()" title="class or interface in java.lang">notify</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#toString()" title="class or interface in java.lang">toString</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#wait()" title="class or interface in java.lang">wait</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
</TR>
</TABLE>
<A NAME="methods_inherited_from_class_java.util.Comparator"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from interface java.util.<A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true" title="class or interface in java.util">Comparator</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.util">equals</A></CODE></TD>
</TR>
</TABLE>
<P>
<!-- ========= CONSTRUCTOR DETAIL ======== -->
<A NAME="constructor_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="1"><FONT SIZE="+2">
<B>Constructor Detail</B></FONT></TH>
</TR>
</TABLE>
<A NAME="JoSQLComparator(java.lang.String)"><!-- --></A><H3>
JoSQLComparator</H3>
<PRE>
public <B>JoSQLComparator</B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A> q)
throws <A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></PRE>
<DL>
<DD>Init this filter with the query.
<P>
<DL>
<DT><B>Parameters:</B><DD><CODE>q</CODE> - The query.
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></CODE> - If there is an issue with the parsing of the query.</DL>
</DL>
<HR>
<A NAME="JoSQLComparator(org.josql.Query)"><!-- --></A><H3>
JoSQLComparator</H3>
<PRE>
public <B>JoSQLComparator</B>(<A HREF="../../../org/josql/Query.html" title="class in org.josql">Query</A> q)
throws <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A>,
<A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></PRE>
<DL>
<DD>Init this file filter with the query already built and parsed.
<P>
<DL>
<DT><B>Parameters:</B><DD><CODE>q</CODE> - The query.
<DT><B>Throws:</B>
<DD><CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A></CODE> - If the Query object has not been parsed.
<DD><CODE><A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></CODE> - If the FROM class is not as expected.</DL>
</DL>
<!-- ============ METHOD DETAIL ========== -->
<A NAME="method_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="1"><FONT SIZE="+2">
<B>Method Detail</B></FONT></TH>
</TR>
</TABLE>
<A NAME="doExecuteOn(java.util.List)"><!-- --></A><H3>
doExecuteOn</H3>
<PRE>
public void <B>doExecuteOn</B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</A> l)
throws <A HREF="../../../org/josql/QueryExecutionException.html" title="class in org.josql">QueryExecutionException</A></PRE>
<DL>
<DD>Execute the EXECUTE ON ALL expressions.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>l</CODE> - The list to execute the expressions on.
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../org/josql/QueryExecutionException.html" title="class in org.josql">QueryExecutionException</A></CODE></DL>
</DD>
</DL>
<HR>
<A NAME="clearCache()"><!-- --></A><H3>
clearCache</H3>
<PRE>
public void <B>clearCache</B>()</PRE>
<DL>
<DD>Clear the cache, it is VITAL that you call this method before you use
the comparator (if it has been used before) otherwise data objects will
be "left around" and preventing the GC from cleaning them up.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
</DL>
</DD>
</DL>
<HR>
<A NAME="isCaching()"><!-- --></A><H3>
isCaching</H3>
<PRE>
public boolean <B>isCaching</B>()
throws <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A></PRE>
<DL>
<DD>Return whether this comparator uses caching to improve performance.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Returns:</B><DD><code>true</code> if caching is on.
<DT><B>Throws:</B>
<DD><CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A></CODE> - If the query has not yet been parsed or set.</DL>
</DD>
</DL>
<HR>
<A NAME="setCaching(boolean)"><!-- --></A><H3>
setCaching</H3>
<PRE>
public void <B>setCaching</B>(boolean b)
throws <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A></PRE>
<DL>
<DD>Set whether the comparator should use caching to improve performance.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>b</CODE> - Set to <code>true</code> to turn caching on.
<DT><B>Throws:</B>
<DD><CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A></CODE> - If the query has not yet been parsed or set.</DL>
</DD>
</DL>
<HR>
<A NAME="compare(java.lang.Object, java.lang.Object)"><!-- --></A><H3>
compare</H3>
<PRE>
public int <B>compare</B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> o1,
<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> o2)</PRE>
<DL>
<DD>Compares the objects as according to the ORDER BY clause.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true#compare(T, T)" title="class or interface in java.util">compare</A></CODE> in interface <CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true" title="class or interface in java.util">Comparator</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>o1</CODE> - The first object.<DD><CODE>o2</CODE> - The second object.</DL>
</DD>
</DL>
<HR>
<A NAME="getException()"><!-- --></A><H3>
getException</H3>
<PRE>
public <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/Exception.html?is-external=true" title="class or interface in java.lang">Exception</A> <B>getException</B>()</PRE>
<DL>
<DD>The <A HREF="/usr/share/doc/default-jdk-doc/api/java/util/Comparator.html?is-external=true#compare(T, T)" title="class or interface in java.util"><CODE>Comparator.compare(Object,Object)</CODE></A> method does not allow for
any exceptions to be thrown however since the execution of the ORDER BY clause
on the objects can cause the throwing of a <A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql"><CODE>QueryParseException</CODE></A> it should
be captured. If the exception is thrown then this method will return it.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Returns:</B><DD>The exception thrown by the execution of the ORDER BY clause in <A HREF="../../../org/josql/utils/JoSQLComparator.html#compare(java.lang.Object, java.lang.Object)"><CODE>compare(Object,Object)</CODE></A>
or by sub-class/interface specific methods, this may be null if no exception was thrown.</DL>
</DD>
</DL>
<HR>
<A NAME="setQuery(java.lang.String)"><!-- --></A><H3>
setQuery</H3>
<PRE>
public void <B>setQuery</B>(<A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A> q)
throws <A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></PRE>
<DL>
<DD>Set a new Query (string form) for use in this filter.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>q</CODE> - The Query to use.
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></CODE> - If there is an issue with the parsing of the query,
or if the FROM class is not as expected.</DL>
</DD>
</DL>
<HR>
<A NAME="setQuery(org.josql.Query)"><!-- --></A><H3>
setQuery</H3>
<PRE>
public void <B>setQuery</B>(<A HREF="../../../org/josql/Query.html" title="class in org.josql">Query</A> q)
throws <A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A>,
<A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></PRE>
<DL>
<DD>Set a new Query object for use in this filter.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>q</CODE> - The Query to use.
<DT><B>Throws:</B>
<DD><CODE><A HREF="/usr/share/doc/default-jdk-doc/api/java/lang/IllegalStateException.html?is-external=true" title="class or interface in java.lang">IllegalStateException</A></CODE> - If the Query object has not been parsed.
<DD><CODE><A HREF="../../../org/josql/QueryParseException.html" title="class in org.josql">QueryParseException</A></CODE> - If the FROM class is not as expected.</DL>
</DD>
</DL>
<HR>
<A NAME="getQuery()"><!-- --></A><H3>
getQuery</H3>
<PRE>
public <A HREF="../../../org/josql/Query.html" title="class in org.josql">Query</A> <B>getQuery</B>()</PRE>
<DL>
<DD>Get the Query we are using to process objects.
<P>
<DD><DL>
</DL>
</DD>
<DD><DL>
<DT><B>Returns:</B><DD>The Query.</DL>
</DD>
</DL>
<!-- ========= END OF CLASS DATA ========= -->
<HR>
<!-- ======= START OF BOTTOM NAVBAR ====== -->
<A NAME="navbar_bottom"><!-- --></A>
<A HREF="#skip-navbar_bottom" title="Skip navigation links"></A>
<TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY="">
<TR>
<TD COLSPAN=2 BGCOLOR="#EEEEFF" CLASS="NavBarCell1">
<A NAME="navbar_bottom_firstrow"><!-- --></A>
<TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3" SUMMARY="">
<TR ALIGN="center" VALIGN="top">
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-summary.html"><FONT CLASS="NavBarFont1"><B>Package</B></FONT></A> </TD>
<TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> <FONT CLASS="NavBarFont1Rev"><B>Class</B></FONT> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="class-use/JoSQLComparator.html"><FONT CLASS="NavBarFont1"><B>Use</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../index-files/index-1.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A> </TD>
<TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A> </TD>
</TR>
</TABLE>
</TD>
<TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM>
</EM>
</TD>
</TR>
<TR>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
<A HREF="../../../org/josql/utils/ExpressionEvaluator.html" title="class in org.josql.utils"><B>PREV CLASS</B></A>
NEXT CLASS</FONT></TD>
<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2">
<A HREF="../../../index.html?org/josql/utils/JoSQLComparator.html" target="_top"><B>FRAMES</B></A>
<A HREF="JoSQLComparator.html" target="_top"><B>NO FRAMES</B></A>
<SCRIPT type="text/javascript">
<!--
if(window==top) {
document.writeln('<A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>');
}
//-->
</SCRIPT>
<NOSCRIPT>
<A HREF="../../../allclasses-noframe.html"><B>All Classes</B></A>
</NOSCRIPT>
</FONT></TD>
</TR>
<TR>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
SUMMARY: NESTED | FIELD | <A HREF="#constructor_summary">CONSTR</A> | <A HREF="#method_summary">METHOD</A></FONT></TD>
<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2">
DETAIL: FIELD | <A HREF="#constructor_detail">CONSTR</A> | <A HREF="#method_detail">METHOD</A></FONT></TD>
</TR>
</TABLE>
<A NAME="skip-navbar_bottom"></A>
<!-- ======== END OF BOTTOM NAVBAR ======= -->
<HR>
<center><dd><a href='http://sourceforge.net'><img border='0' height='31' width='88' title='SourceForge' src='http://sourceforge.net/sflogo.php?group_id=josql&type=1' />  </a>Copyright © 2010 Gary Bentley. All Rights Reserved.</dd></center>
</BODY>
</HTML>
|