Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 &:]ej6V'[
U};~ff+
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 28u3B2\$
@<n8?"{5S
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 DK\Ud6w
,PmQ}1kGW
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 L%hVts'
be@\5
。 ZxvqLu
}DCR(p rD
分页支持类: e*nT+Rp
S2^Ckg
java代码: Cp`>dtCd
W*S!}ZT`
8 !{;yz
package com.javaeye.common.util; +Jf45[D
a>_Cxsb&`
import java.util.List; D'nO
834E
]2
publicclass PaginationSupport { "s?!1v(v
*5Mg^}ZC5
publicfinalstaticint PAGESIZE = 30; 1cA4-,YO>
JA")L0a_
privateint pageSize = PAGESIZE; KS9eV
uU|fCwQt
privateList items; Ts~MkO
| e&v;48
privateint totalCount; }3}{} w0Y
Vm3e6Y,K
privateint[] indexes = newint[0]; A_:YpQ07@
|Z"5zL10
privateint startIndex = 0; CH`_4UAX%
L\`uD[g
public PaginationSupport(List items, int ox}LC,!
gG>|5R0
totalCount){
>k\lE(
setPageSize(PAGESIZE); D09/(%4j
setTotalCount(totalCount); e>GX]tK
setItems(items); @D'NoA@1A
setStartIndex(0); Dej2-Y
} \Y?ByY
_NkVi_UX
public PaginationSupport(List items, int 6)@Y 41H]C
SccaX
P
totalCount, int startIndex){ |q(
.j4[i
setPageSize(PAGESIZE); C}7c:4c
setTotalCount(totalCount); ne~=^IRB
setItems(items); BB>R=kt
setStartIndex(startIndex); _Di";fe?
} LKEf#mp
NrNxI'MG
public PaginationSupport(List items, int hxedQvW
[q<Vm-
totalCount, int pageSize, int startIndex){ ZQ0R3=52r
setPageSize(pageSize); O.9r'n4f
setTotalCount(totalCount); |3h-F5V)
setItems(items); X}Oo5SNgff
setStartIndex(startIndex); 'f?=ks<
} ]csfK${
j$he5^GC
publicList getItems(){ {dbPMx
return items; ^xpiNP!?a
} ;1wRo`RD
npJyVh47
publicvoid setItems(List items){ w7;,+Jq
this.items = items; #cZ<[K q6
} K).Gj2 $
:M |<c9I
publicint getPageSize(){ LXGlG
return pageSize; [ITtg?]F
} +im>|
JF+E.-fy$
publicvoid setPageSize(int pageSize){ HZ+l){u
this.pageSize = pageSize; qkLp8/G>pO
} SGp}(j>
q>E[)\+y
publicint getTotalCount(){ fBi6%
#
return totalCount; Zdm7As]
} P>i!f!o*I
#7Pnw.s3zz
publicvoid setTotalCount(int totalCount){ m"r=p
if(totalCount > 0){ y>5??q
this.totalCount = totalCount; Jw
b'5[R
int count = totalCount / ~h<<-c
DUAI
pageSize; dpTeF`N
if(totalCount % pageSize > 0) TrEo5H ;
count++; (sfy14>\
indexes = newint[count]; 9c}mAg4
for(int i = 0; i < count; i++){ XuY#EJbZ
indexes = pageSize * k|SywATr
?q%&"
i; Y]33:c_;Mo
} j-R9=vB2
}else{ >p[skN
this.totalCount = 0; [PI!.9H
} DMc H, _(
} G|h@O'
JJ+A+sfdk
publicint[] getIndexes(){ JSAbh\Mq6
return indexes; Vp.&X 8
} TGxmc37?
H E'1Wa0r
publicvoid setIndexes(int[] indexes){ hYI0S7{G
this.indexes = indexes; ?##3E,
/"9
} NO%x
2dx0
E;vF
:?|
publicint getStartIndex(){ A'=,q
return startIndex; Bc!ZHW*&
} *2(W`m
r) SG!;X
publicvoid setStartIndex(int startIndex){ {+SshT>J
if(totalCount <= 0) #j?SdQ
this.startIndex = 0; yt@;yd:OEk
elseif(startIndex >= totalCount) 6HK
dBW$/
this.startIndex = indexes c2,;t)%@E
eM1=r:jgE
[indexes.length - 1]; 0YApaL+jt
elseif(startIndex < 0) O.HaEg/-
this.startIndex = 0; t
V:oBT*
else{ ,e{|[k
this.startIndex = indexes ydx-`yg#
O5lP92],
[startIndex / pageSize]; qVidubsW
} Ug1[pONk
} l"ZfgJ}W
uh8+Y%V
p
publicint getNextIndex(){ OZ9ud ]@\
int nextIndex = getStartIndex() + KBO{g:"
Vo; B#lK
pageSize; nbhzLUK
if(nextIndex >= totalCount) @TWt M#
return getStartIndex(); jb5nL`(j$
else n G+ L'SmI
return nextIndex; f]*_]J/
} YM(`E9{h
Z`9yGaTO
publicint getPreviousIndex(){ j&qJK,~
int previousIndex = getStartIndex() - '(4#He?Gd
fho$:S
pageSize; -j<g}IG
if(previousIndex < 0) yE80*C~d
return0; 6 pQbh*
else aV6l"A]
return previousIndex; [:MpOl-KIz
} _Q
$D6+
QSNLo_z
} eT4+O5t
{Y p;R
'~Z#h P
Mb2rHUr
抽象业务类 "V>7u{T
java代码: 9W~3E^x
S(b5Gj/Kd
y9>?
/** ,fQs+*j
* Created on 2005-7-12 CK{.Ic^
*/ 2Q/#.lNL
package com.javaeye.common.business; 7LB#\2
JuD$CHg;#
import java.io.Serializable; HVz,liq
import java.util.List; T5jZd@VT,
>UQ`@GdafR
import org.hibernate.Criteria; @Qa)@'u
import org.hibernate.HibernateException; ~H0WHqcy
import org.hibernate.Session; %NI'PXpI
import org.hibernate.criterion.DetachedCriteria; q%/ciPgE
import org.hibernate.criterion.Projections; 1aAYBV<3
import Q%AD6G(7
Fs bX{
org.springframework.orm.hibernate3.HibernateCallback; OFtAT@=O
import z+J4XpX0,
Hsoe?kUHF
org.springframework.orm.hibernate3.support.HibernateDaoS 4*<27
1HBdIWhHv.
upport; SAa
hkX
wkp|V{k
import com.javaeye.common.util.PaginationSupport; <^Hh5kfS'
r|bvpZV
public abstract class AbstractManager extends +QqEUf<U*,
cX64 X
HibernateDaoSupport { 54A ndyeA
8")1,
privateboolean cacheQueries = false; L%7?o:
X5@rPGc
privateString queryCacheRegion; -9 AI@^q
E+ 65
publicvoid setCacheQueries(boolean p^LUyLG`
FL5tIfV+
cacheQueries){ hE-u9i
this.cacheQueries = cacheQueries; F?LTWm
} D [#1~M
=;1MpD
publicvoid setQueryCacheRegion(String Tv;|K's'
#nL&x3
queryCacheRegion){ 8bB'[gJ]{
this.queryCacheRegion = ypuW}H%`
C#5z!z/:%
queryCacheRegion; %h ?c
} LWb5C{
_Z:WgO].
publicvoid save(finalObject entity){ ak?XE4-N
getHibernateTemplate().save(entity); D/CSR=b
} Xm7Nr#
ZQHANr=
6
publicvoid persist(finalObject entity){ f1'NWec
getHibernateTemplate().save(entity); c%uX+\-$
} :VPZGzK4
B6gSt3w.
publicvoid update(finalObject entity){ A22h+8yG
getHibernateTemplate().update(entity); ( _ZOUMe
} zL@ZNH
[T;0vv8
publicvoid delete(finalObject entity){ )w8h2=l
getHibernateTemplate().delete(entity); 9:bC{n
} CL*i,9:NR
yIwAJl7Xf
publicObject load(finalClass entity, f$x\~y<[
9HlRf6S
finalSerializable id){ bBkF,`/f$
return getHibernateTemplate().load Q']
_3
21$YZlhJ
(entity, id); AepAlnI@
} JDi|]JY
s@sr.'yU
publicObject get(finalClass entity, b!Q|0X.?
8_MR7'C1hi
finalSerializable id){ aClXg-
return getHibernateTemplate().get ]q0mo1-EZ!
V`V
Z[
(entity, id); -{i;!XE$SR
} @N`) Z3P+
'aQ"&GX@
publicList findAll(finalClass entity){ 3_W1)vd{
return getHibernateTemplate().find("from **V^8'W<
[q/=%8qLUA
" + entity.getName()); O|J`M2r
} W'2|hP
O_#Ag K<A
publicList findByNamedQuery(finalString XV+s 5C
u/e-m/
namedQuery){ vu[+UF\G
return getHibernateTemplate 7z'l}*FRD
<@9p|[!
().findByNamedQuery(namedQuery); 3jIi$X06
} #pbPaRJL(
g&y'#,'Q~,
publicList findByNamedQuery(finalString query, (MiEXU~v
P SDzs\s
finalObject parameter){ 7@u0;5p|
return getHibernateTemplate SF2A?L?}+
)A9K9pZj
().findByNamedQuery(query, parameter); N\ ?%944R
} Ep/4o<N(
9^Q:l0|
publicList findByNamedQuery(finalString query, ~d :Z|8
> $0eRVL
finalObject[] parameters){ 6CBk,2DswI
return getHibernateTemplate {dV#"+
]w.:K*_=
().findByNamedQuery(query, parameters); 76a+|TzR
} 3!M;Z7qF]
$E@L{5Yt
publicList find(finalString query){ N!>Gg|@~
return getHibernateTemplate().find z5PFppSQ
TQDb\d8,f
(query);
*jo y%F
} Bi9b"*LN
(3`Q`o;
publicList find(finalString query, finalObject 8 munw
OI"vC1.5
parameter){ f>i6f@
return getHibernateTemplate().find Q.Hy"~
w}VS mt$F
(query, parameter); ^~Nz8PCY
} fyIL/7hzf4
(#FWA<o
public PaginationSupport findPageByCriteria bj4cW\b(
6]^;
s1!
(final DetachedCriteria detachedCriteria){ =s`\W7/;{-
return findPageByCriteria ]Ln2|$R
Cdl#LVqs
(detachedCriteria, PaginationSupport.PAGESIZE, 0); <d~P;R(@
} *(@(9]B~
6r/NdI
public PaginationSupport findPageByCriteria [8AGW7_
PLR[nB7K
(final DetachedCriteria detachedCriteria, finalint Z- ;<R$
@K/}Ob4
startIndex){ v;"[1w}
return findPageByCriteria 4jefU}e9#
%E Jv!u*-
(detachedCriteria, PaginationSupport.PAGESIZE, n5dFp%k
X=)Ue
startIndex); @O9.~6
} Q{6Bhx *>
/gT$ d2{
public PaginationSupport findPageByCriteria ez_qG=J .
F2!C^r,~L
(final DetachedCriteria detachedCriteria, finalint 4]O{Nko)
h}fz`ti U
pageSize, \G}EI|Wo
finalint startIndex){ o
%sBU
return(PaginationSupport) An cmSi
;Ut0tm
getHibernateTemplate().execute(new HibernateCallback(){ |SC^H56+
publicObject doInHibernate @s RRcP~
K5gh7
(Session session)throws HibernateException { +@[T0cXp
Criteria criteria = p
x1y#Q
'EoJo9p6}
detachedCriteria.getExecutableCriteria(session); WGFp<R
int totalCount = HbQ `b
Pn|A>.)z
((Integer) criteria.setProjection(Projections.rowCount tcyami6D4
Xh"JyDTj3
()).uniqueResult()).intValue(); P F#+G;q;
criteria.setProjection O@r%G0Jge
<6g{vNA
(null); lPyGL-Q
List items = QPf*!E
,.[T]37
criteria.setFirstResult(startIndex).setMaxResults SskvxH+7
PjZsMHW%
(pageSize).list(); zu}oeAQc$
PaginationSupport ps = yq+'O&+
+-YMW;5
new PaginationSupport(items, totalCount, pageSize, U_ n1QU
y<(q<V#0!S
startIndex); vI3L <[W
return ps; Zg1=g_xY
} <uZ
r.X
}, true); %suSZw`
} .%;`:dtj
:VpRpj4f
public List findAllByCriteria(final _u TaN
tE3#Uq
DetachedCriteria detachedCriteria){ !h3$C\
return(List) getHibernateTemplate _/Ky;p.
!J`>;&
().execute(new HibernateCallback(){ t}L kl(
publicObject doInHibernate Qgx9JJ>
ggQ/_F8u
(Session session)throws HibernateException { ^R- -&{I
Criteria criteria = iJ n<
2"+8NfFl
detachedCriteria.getExecutableCriteria(session); JDPn
return criteria.list(); {I'8+~|pZL
} #MkXio; h
}, true); o %GVg
} Er/h:=
V4I5PPz~
public int getCountByCriteria(final 4/UY*Us&
u#(VR]u\7
DetachedCriteria detachedCriteria){ u5D@,wSNz
Integer count = (Integer) \fC)]QZ
)CgKZ"
getHibernateTemplate().execute(new HibernateCallback(){ ..jc^'L
publicObject doInHibernate %oPW`r
Bgb~ Tz'
(Session session)throws HibernateException { t&scvXh
Criteria criteria = Zo$,{rl
K1y]
detachedCriteria.getExecutableCriteria(session); D{'>G@nLQ
return a,eR'L<"*-
Pw c)u&
criteria.setProjection(Projections.rowCount 9*fA:*T
K4w %XVaH
()).uniqueResult(); 25EuVj`zL
} pO]{Y?X:
}, true); yFt$L'#
return count.intValue(); 2ed4xhV
} ~x67v+I
}
HJ5 Ktt
'7BJ.
+]?/c>M
sA^_I6>M"
X8(H#Ef[
.T!R]n
用户在web层构造查询条件detachedCriteria,和可选的 r.-U=ql
tj ONN(K`
startIndex,调用业务bean的相应findByCriteria方法,返回一个 D,$!.5OA
d}d1]@Y\
PaginationSupport的实例ps。 Evjvaa^
(i3V[H
ps.getItems()得到已分页好的结果集 lI,lR
ps.getIndexes()得到分页索引的数组 ;Gf,I1d}{
ps.getTotalCount()得到总结果数 KImBQ2 ^Tu
ps.getStartIndex()当前分页索引 aC!e#(q
ps.getNextIndex()下一页索引 _ ^ JhncL
ps.getPreviousIndex()上一页索引 YgiLfz iT
,=Q;@Z4 vJ
LgG7|\(-
Kivr)cIG
2Ra}&ie
)># Y,/q
8%+F.r
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 eT!*_.' e
]TE(:]o7V
,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
AqqD!
!
.q,m>?+
一下代码重构了。 W't?aj I|
jH5VrN*Q
我把原本我的做法也提供出来供大家讨论吧: h4iz(*
>]ghme
首先,为了实现分页查询,我封装了一个Page类: [ClDKswq
java代码: /
5\gP//9K
#
dA-dN
e7O9q8b
/*Created on 2005-4-14*/ H\>0jr`
package org.flyware.util.page; ^i"~6QYE
:m&cm%W]ts
/** R>C^duos.
* @author Joa UnE[FYx
* tyI!y~-z
*/ =/#+,
publicclass Page { eb` !
:cE6-Fv
/** imply if the page has previous page */ uc~/l4~N
privateboolean hasPrePage; /#FU"
Yl$R$u)
/** imply if the page has next page */ H^d2|E[D
privateboolean hasNextPage; }G/#Nb)
7u=R5
/** the number of every page */
t@#l0lu$
privateint everyPage; !T|q/ri
swTur
/** the total page number */ o5(~nQ
privateint totalPage; _\ &