Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 x6x6N&f?
fV.43E
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 zA/W+j$:
pPG@_9qf
据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 `|^<y.-6
E4'D4@\W
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 '#.:%4
B&m?3w
。 6YZ&>`a^
wzMWuA4vX
分页支持类: Ye}y_W
n~d`PGs?f
java代码: }m<)$.x|P
dMwVgc:
[vaG{4m
package com.javaeye.common.util; ^IGTGY]s
A{E0 a:v
import java.util.List; Y4Z?`TL
Xklp6{VH9
publicclass PaginationSupport { NwG&uc+Q
9CWUhS
publicfinalstaticint PAGESIZE = 30; ytmlG%
1*r{%6
privateint pageSize = PAGESIZE; w
I@
lO\
[21tT/
privateList items; Iq\sf-1E
XY|-qd}A
privateint totalCount; b['TRYc=:
):+H`Hcm
privateint[] indexes = newint[0]; k-
sbZL
" I@Z:[=2
privateint startIndex = 0; V]PTAhc
$XI5fa4Tt
public PaginationSupport(List items, int _pNUI{De
"7)F";_(^
totalCount){ kx1-.~)p(z
setPageSize(PAGESIZE); d~|qx
setTotalCount(totalCount); ^ D
B0C
setItems(items); ;<q@>p[
setStartIndex(0); /:e|B;P`k
} {F
k]X#j
F,O+axO
ja
public PaginationSupport(List items, int )}c$n
+X;6%O;
totalCount, int startIndex){ ]'_z(s}
setPageSize(PAGESIZE); L#u6_`XJ+
setTotalCount(totalCount); _jZDSz|Yb
setItems(items); nwN<Q\]S
setStartIndex(startIndex); KX<RD|=
} jVRd[
}
2)s%
public PaginationSupport(List items, int D2!ww{t
LTtfOcrt
totalCount, int pageSize, int startIndex){ -r-`T
s
setPageSize(pageSize); \lR~!6:
setTotalCount(totalCount); =WEfo;
setItems(items); ;gm){ g
setStartIndex(startIndex); &,&+/Sr11
} @R2|=ox
\hM6 ykY-
publicList getItems(){ >uOc#+5M.
return items; >M:5yk@
} 4g1u9Sc0
K)Db3JIIk
publicvoid setItems(List items){ CaBTqo
this.items = items; &9s6p6eb
} $zmES tcm
/2HwK/RZ
publicint getPageSize(){ LwGcy1F.
return pageSize; x2ol
} RV(}\JU
+Kq>r|;
publicvoid setPageSize(int pageSize){ h'-TZXs0e1
this.pageSize = pageSize; 2|%30i,vV
} ;*Z
w}51
Y5MHd>m
publicint getTotalCount(){ m'qMcCE
return totalCount; ^m1Rw|
} .X2mEnh
c>UITM=!I
publicvoid setTotalCount(int totalCount){ 2CxdNj
if(totalCount > 0){ ?|hzAF"U
this.totalCount = totalCount; e#'`I^8l
int count = totalCount / KFV]2mFN
wqGZkFg1
pageSize; 2tr2:PB`
if(totalCount % pageSize > 0) pb{P[-f
count++; 5e2mEQU>
indexes = newint[count]; [
objdQU`
for(int i = 0; i < count; i++){ ^5T{x>Lj
indexes = pageSize * e2*^;&|%
IeU.T@ $
i; x9_ Lt4
} H7SqM D*y9
}else{ +Zr03B
this.totalCount = 0; zIo))L
} @W @L%<
} g{J3Ba
9M7P]$^
publicint[] getIndexes(){ ev?>Nq+Z
return indexes; d;;=s=j
} )nJ>kbO~8
@P.l8|w
publicvoid setIndexes(int[] indexes){ vGAPQg6*
this.indexes = indexes; ?APzx@$D.
} ~b7Nzzfo
s=q+3NTv
publicint getStartIndex(){ -xcz+pHQ
return startIndex; e+6~JbMV
} 8D n]`}ok
r=w%"3vb^
publicvoid setStartIndex(int startIndex){ 7]v-2
*
if(totalCount <= 0) wM&G-~9ujk
this.startIndex = 0; fzKKK+
elseif(startIndex >= totalCount) YT:1=Nf}
this.startIndex = indexes c"z%AzUV'
9/%|#b-z
[indexes.length - 1]; N4Lk3]
elseif(startIndex < 0) iK#{#ebAoW
this.startIndex = 0; _N]yI0k(
else{ ,H%\+yn{
this.startIndex = indexes eQLa .0
=_1" d$S&
[startIndex / pageSize]; ld?M,Qd
} JIQzP?+?
} O:x=yj%^
4Ek<
5s[
publicint getNextIndex(){ YW}/C wB
int nextIndex = getStartIndex() + 95<:-?4C;W
RTU:J67E
pageSize; S;c=6@"
if(nextIndex >= totalCount) {l6]O
return getStartIndex(); W[?B@ sdSZ
else )5t_tPv
return nextIndex; Qpc{7#bp
} xl9l>k6,
lxd<^R3i#^
publicint getPreviousIndex(){ dg!sRm1iZ:
int previousIndex = getStartIndex() - UEe qk"t^
bCrB'&^t
pageSize; 2<O8=I _
if(previousIndex < 0) f6"j-IW[z
return0; us cR/d
else E.6\(^g
return previousIndex; ~9c9@!RA2
} aj,ZM,Ad
C[pDPx,#:G
} MQ+ek4
3edAI&a5
Iu[EUi!"
f
LW>-O73
抽象业务类 Vg+SXq6G
java代码: {k*_'0
qa~[fORO[
CL*%06QyE
/** '!I?C/49k
* Created on 2005-7-12 ,J^Op
*/ .3&m:P8zV
package com.javaeye.common.business; ,*4"d._Y
NLpD,q{
import java.io.Serializable; G#V22Wca8
import java.util.List; e>^R 8qM?
P2p^jm
import org.hibernate.Criteria; }:mI6zsNj
import org.hibernate.HibernateException; %FU[j^
import org.hibernate.Session; ?MYD}`Cv
import org.hibernate.criterion.DetachedCriteria; la4,Z
import org.hibernate.criterion.Projections; HA%ye"(y8
import Esjv^* v9-
M($},xAvDU
org.springframework.orm.hibernate3.HibernateCallback; >
95Cs`>d
import (`NRF6'&1L
[jw o D
org.springframework.orm.hibernate3.support.HibernateDaoS ;Ki1nq5c#s
w}0Qy
upport; q{hq. KZ
$T4PC5.
import com.javaeye.common.util.PaginationSupport; {5udol5?
jveRiW@
public abstract class AbstractManager extends @\y7
9FX
P1QJ'eC;T
HibernateDaoSupport { Kq$Zyf=E
ie!4z34
privateboolean cacheQueries = false; W!k6qTz)
Mb>XM7}PU
privateString queryCacheRegion; 1I`D$Xq~:
07|NPS
publicvoid setCacheQueries(boolean B<LavX>F
%&XX*&
q
cacheQueries){ kTz
this.cacheQueries = cacheQueries; oc(bcU
} rd))H
*eP4dGe&
publicvoid setQueryCacheRegion(String o zYI/b^
Pb,^UFa=
queryCacheRegion){ o,yvi
this.queryCacheRegion = yLx.*I^6
[q&J"dt
queryCacheRegion; q,DX{:
} Ic
K=E]p
LXLDu2/@
publicvoid save(finalObject entity){ 2YKM9Ks
getHibernateTemplate().save(entity); SDIeq
} fF("c6:w(
j,xPN=+hT
publicvoid persist(finalObject entity){ }gW/heUE
getHibernateTemplate().save(entity); w8
$Qh%J'<
} 6iG<"{/U5
ib_Gy77Os
publicvoid update(finalObject entity){ X6 ,9D[Nw
getHibernateTemplate().update(entity); ^wa9zs2s;/
} <k](s
0EOX@;}
publicvoid delete(finalObject entity){ q4i8Sp>
getHibernateTemplate().delete(entity); j6vZ{Fx;w
} $:[BB,$
0*?XQV@
publicObject load(finalClass entity, yV/ J(
SN(=e#ljE
finalSerializable id){ noA\5&hqW
return getHibernateTemplate().load )6&\WNL-x
pT@!O}'$
(entity, id); \&5@ yh
} LG#w/).^
P|4E1O
publicObject get(finalClass entity, ]$*{<
1H=wl=K
finalSerializable id){ e@=[+iJc
return getHibernateTemplate().get 7omGg~!k(
i4n
b#
(entity, id); Iv72;ZCh?6
} ]7kGHIJ|
s ;s-6%p
publicList findAll(finalClass entity){
|WU`p
return getHibernateTemplate().find("from nnL$m_K~
oks=|'&
" + entity.getName()); _]UDmn[C
} 9*;isMkq<
;j U-<
publicList findByNamedQuery(finalString -]\E}Ti
df6Ν4L
namedQuery){ 9K46>_TyH
return getHibernateTemplate I~LQ1_
MLBg_<
().findByNamedQuery(namedQuery); kA%OF*%|6
} .k`*$1?73x
Kxc$wN<
publicList findByNamedQuery(finalString query, 5
?~-Vv31s
_MbVF>JOx
finalObject parameter){ &8+6!TN7
return getHibernateTemplate V-;nj,.mY
3B".Gsm)X
().findByNamedQuery(query, parameter); (4ci=*3=
} CY3 \:D0I
8[1DO1*P
publicList findByNamedQuery(finalString query, mK40 f
^la i!uZVa
finalObject[] parameters){ LnTe_Q7_
return getHibernateTemplate @MZ6E$I
x;FO|fH
().findByNamedQuery(query, parameters); mnQjX ?
} QP5:M!O<)
xrVZxK:!
publicList find(finalString query){ h2|vB+W-
return getHibernateTemplate().find 9U9c"'g
'%-xe3
(query); ;Nf hKu%K
} mXU?+G0
aI{@]hCo
publicList find(finalString query, finalObject KPjqw{gR_R
wGzXp5
dl
parameter){ 'RV\}gqZ
return getHibernateTemplate().find qa$[L@h>
+z(,A
(query, parameter); m0A@jWgd
} k;fnC+Y$s
YY:iPaGO
public PaginationSupport findPageByCriteria wAYzR$i
im\YL<
(final DetachedCriteria detachedCriteria){ a&s"#j
return findPageByCriteria H"FflmUO
I"cQ5gF?A
(detachedCriteria, PaginationSupport.PAGESIZE, 0); x-V' 0-#U>
} /ik)4]>
jO&f*rxN
public PaginationSupport findPageByCriteria 9SH<d)^
Gp ^ owr
(final DetachedCriteria detachedCriteria, finalint ;h-G3>Il
Z|:_c
startIndex){ Og$eQS
return findPageByCriteria Ag>>B9
fb0T/JTw
(detachedCriteria, PaginationSupport.PAGESIZE, W}R=
+wz`_i)!
startIndex); QVSsi
j
} -wtTq
ph'
"`jZ(+
public PaginationSupport findPageByCriteria 1!;"bHpk
SJ@8[n.x
(final DetachedCriteria detachedCriteria, finalint yToT7 X7F7
il IV}8
pageSize, !QQ<Ai!E
finalint startIndex){ g~Nij~/
return(PaginationSupport) 1FD7~S|
f`u5\!}=!
getHibernateTemplate().execute(new HibernateCallback(){ XgiI6-B~
publicObject doInHibernate ^;)SFmjg%
]*g ss'N
(Session session)throws HibernateException { (iCZz{l@~
Criteria criteria = Nn,vdu{^2
K{=r.W
detachedCriteria.getExecutableCriteria(session); UPVO~hB;
int totalCount = '#McY'.D T
KM_)7?`
((Integer) criteria.setProjection(Projections.rowCount []=FZ`4
C NzSBm
()).uniqueResult()).intValue(); cy&
criteria.setProjection yRq8;@YGY
u]1-h6
(null); AF*ni~
List items = *C3uMiz
oz\{9Lwc
criteria.setFirstResult(startIndex).setMaxResults uFrJ:l+
A{i][1N
(pageSize).list(); x;ERRK
PaginationSupport ps = $vg moJ@X0
5S|}:~7T
new PaginationSupport(items, totalCount, pageSize, q*F~~J!P
]} 5I>l
startIndex); ++T
"+p
return ps; d6t)gG*5
} H;TOPtt2
}, true); +Dq|l}
} VGTeuu5i
HC9vc,Fp
public List findAllByCriteria(final RR~sEUCo{
)T.pjl
DetachedCriteria detachedCriteria){ <<7,kfR
return(List) getHibernateTemplate 8`AcS|k
xP{HjONu
().execute(new HibernateCallback(){ {*M>X}voS
publicObject doInHibernate `eMrP`
dt-Qu},8-
(Session session)throws HibernateException { 0^<Skm27"
Criteria criteria = ~!3t8Hx6
/@9-!cL
detachedCriteria.getExecutableCriteria(session); ;I!+lx3[
return criteria.list(); R
(tiIo
} DU/9/ I?~
}, true); 2_oK5*j
} nu469
t5ny"k!
public int getCountByCriteria(final
w2uRN?
;S=62_Un
DetachedCriteria detachedCriteria){ @MN}^umx`
Integer count = (Integer) ;e#>n!<u
*tTP8ZCQ[
getHibernateTemplate().execute(new HibernateCallback(){ u=d`j
publicObject doInHibernate v5&xY2RI7
XJ
f+Eh
(Session session)throws HibernateException { 1V*8,YiC<
Criteria criteria = hb /8Q
.KT 7le<Zm
detachedCriteria.getExecutableCriteria(session); hV3,^#9o
return 'WKu0Yi^'
WX%h4)z*
criteria.setProjection(Projections.rowCount mC*W2#1pF
}"%!(rx
()).uniqueResult(); di]$dl|Wi
} rt5oRf:wY
}, true); SE-!|WR
return count.intValue(); ^w;o \G
} _qC+'RE3
} `YFkY^T
yM (_P0
#6*V7@9]3|
ZfFIX5Qd\
tIi!*u
U7nsMD
用户在web层构造查询条件detachedCriteria,和可选的 BpQ;w,sefq
pX>ua5Z
startIndex,调用业务bean的相应findByCriteria方法,返回一个 7%:??*"~
Qq`3S>
PaginationSupport的实例ps。 652u Z};e
bjM-Hd/K
ps.getItems()得到已分页好的结果集 K?h[.`}
ps.getIndexes()得到分页索引的数组 07$/]eO%C
ps.getTotalCount()得到总结果数 2k.S[?)
ps.getStartIndex()当前分页索引 cOzg/~\1
ps.getNextIndex()下一页索引 *fxep08B
ps.getPreviousIndex()上一页索引 F`YFo)W
lEO?kn.:z
S2koXg(
p&k0Rx0Q3
'P@=/
ucQezmie
G*)s%2c>h
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (A7T}znG
*)j@G:
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 (/T+Wpy?
XoDJzrL#
一下代码重构了。 )x$!K[=
,3w I~j=
我把原本我的做法也提供出来供大家讨论吧: #rhVzN-?)W
2LCc
首先,为了实现分页查询,我封装了一个Page类: Nbgp_:{
java代码: pd=7^"[};
N; rXl8
b*lKT]D,
/*Created on 2005-4-14*/ S9OxI$6Y
package org.flyware.util.page; hVlyEsLg
&E.OyqGZV
/** !d:tIu{)
* @author Joa U3mXm?f
* 0^J*+
*/ )vO_sIbnW
publicclass Page { +V2C}NQ5R
tH-gaDj_
/** imply if the page has previous page */ @Djs[Cs<*
privateboolean hasPrePage; vg+r?4Q3
X tJswxw`K
/** imply if the page has next page */ ^OHZ767v
privateboolean hasNextPage; 'jh2**i 34
zSEr4^Dk4
/** the number of every page */ V8-4>H}Cb/
privateint everyPage; YH6snC$u
*}+R{
/** the total page number */ IetCMp
privateint totalPage; ceqFQ
E2>im>p
/** the number of current page */ t@X M /=d
privateint currentPage; 3wV86tH%
^it4z gx@
/** the begin index of the records by the current F?!FD>L{`
BfX%|CWh
query */ 0Wa#lkn$I
privateint beginIndex; g;$E1U=R-E
HkW/G[7x&
f&K}IM8& #
/** The default constructor */ Q]!6uA$A
public Page(){ cL6 6gOEL
wG_4$kyj
} Sq?,C&LsA
EJO.'vQ
/** construct the page by everyPage 4;?1Kb#
* @param everyPage Y3D3.T6Q
* */ D 5=C^`$2
public Page(int everyPage){ fW(;
this.everyPage = everyPage; *zJD$+Fo
} #]"/{Z
2q+la|1Cr
/** The whole constructor */ DKR<W.!*t
public Page(boolean hasPrePage, boolean hasNextPage, OdO{xG G@
{PL,VY)Z
baqn7k"
int everyPage, int totalPage, 7^HpVcSM
int currentPage, int beginIndex){ rZ pbu>S
this.hasPrePage = hasPrePage; C=8H)Ef,l
this.hasNextPage = hasNextPage; cvxIp#FbW
this.everyPage = everyPage; ,&0Z]*
this.totalPage = totalPage; L+_8QK <
this.currentPage = currentPage; Xu6jHJ@ x
this.beginIndex = beginIndex; Xz8$Xz,O
} g .3f2w
!
&y
/** JAN|aCzD
* @return ,Ie<'>hd
* Returns the beginIndex. tzZ|S<e6=\
*/ 6!@0VI&P
publicint getBeginIndex(){ tAaYL
\~
return beginIndex; &.hoCPo$
} JL@F~U9
v<j2L"bj
/** W^w d
([
* @param beginIndex *`%4loW
* The beginIndex to set. ~M*7N@D
*/ T)`gm{T
publicvoid setBeginIndex(int beginIndex){ #uB[&GG}W
this.beginIndex = beginIndex; Yi[4DfA
} .a {QA
V_jiOT!
/** ZHz^S)o\[s
* @return B.El a
* Returns the currentPage. FZeP<Ban
*/ U8E0~[y'
publicint getCurrentPage(){ *jGPGnSo
return currentPage; (yfXMp,x
} ]XY0c6
<
4AJ9`1d4
/** P>|Ef~j
* @param currentPage v< Ty|(gd
* The currentPage to set. K@HLIuz4t
*/ _<XgC\4O|
publicvoid setCurrentPage(int currentPage){ k/U>N|5
this.currentPage = currentPage; R !9qQn?
} 3zbXAR*
v C^>p5F
/** ATo}FL 2
* @return $-Cy
* Returns the everyPage. #o~[1K+Yq
*/ YjX*)Q_sl?
publicint getEveryPage(){ a"k'm}hVY$
return everyPage; |"_ )zQ
} )t5;d
>n(F4C-pl
/** TFYw
* @param everyPage t]4!{~,
* The everyPage to set. vpi l$Uq
*/ &