Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 c~O
Lr
xm1'
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 $(+xhn(O
#oFyi @U
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 93:oXyFjD
)QRT/, ;c
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Xdo\DQn
s^SU6P/]
。 ~,E }^
2~l7WW+lx,
分页支持类: $v[mIR
PH%'^YAl7
java代码: +RJKJ:W
[7d(PEQL`
7}y@VO6]
package com.javaeye.common.util; JqZt1um
]1XtV<
import java.util.List; X7AxI\h
0nL
#-`S
publicclass PaginationSupport { ZSW@,Ti
^<-)rzTI
publicfinalstaticint PAGESIZE = 30; @eeI4Jz
0ju-l=w
privateint pageSize = PAGESIZE; m;\nMdn
24k]X`/n
privateList items; FU/:'/ L
3)ox8,{%}
privateint totalCount; sve} ent
TukhGgmF
privateint[] indexes = newint[0]; m_CWVw
WeaT42*Q{
privateint startIndex = 0; 0%%U7GFB5
HR"clD\{Di
public PaginationSupport(List items, int ZJU
%&@
cu
foP&
totalCount){ bGL} nPo
setPageSize(PAGESIZE); j5" L
setTotalCount(totalCount); =}Zl
E
setItems(items); 036m\7+Qj
setStartIndex(0);
[?|yQ x
} Gf3-%s xA
D
(8Z90
public PaginationSupport(List items, int !-^oU"
JDZuT#
totalCount, int startIndex){ 7gN;9pc$
setPageSize(PAGESIZE); h U-FSdR
setTotalCount(totalCount); ui,!_O .c
setItems(items); 2ua!<^,
setStartIndex(startIndex); Z!~_#_Ugl
} KJ32L
du$M
public PaginationSupport(List items, int B
}euIQB
R*2N\2
totalCount, int pageSize, int startIndex){ Qs
za,09
setPageSize(pageSize); )1B?<4
setTotalCount(totalCount); e+-#/i*
setItems(items); qpjZ-[UC
setStartIndex(startIndex); 0$c(<+D
} b way+lh
HVoPJ!K3
publicList getItems(){ zps=~|
return items; F"k`PF*b
} bAH<h
^*`#+*C
publicvoid setItems(List items){ A :KZyd"Z
this.items = items; >I5Wf/$
} G .<0^q,
wU!-sf;]y
publicint getPageSize(){ yOQae m^O
return pageSize; G^nG^HTo5
} \1joW#
FCEmg0qdjD
publicvoid setPageSize(int pageSize){ x$` lQ%
this.pageSize = pageSize; Vf~-v$YI
} D!Y@Og.
PkyX,mr#1
publicint getTotalCount(){ +@!\3a4!
return totalCount; >'q]ypA1
} -r<8mL:yW
j>;1jzr2}
publicvoid setTotalCount(int totalCount){ UakVmVN/P
if(totalCount > 0){ kP[fhOpn
this.totalCount = totalCount; |3E|VGm~
int count = totalCount / V6[jhdb
7L&,Na
pageSize; 6M7GPHah
if(totalCount % pageSize > 0) ?+7~E8
count++; H
$Az,-P
indexes = newint[count]; j0+D99{R
for(int i = 0; i < count; i++){ WO9vOS>
indexes = pageSize * #tHYCSr]
Io JI|lP
i; B,_K mHItd
} Ew{*)r)m
}else{ KG(FA
this.totalCount = 0; 6?%$e$s
} ^.)0O3oC
} 1+-Go}I
]U'zy+
publicint[] getIndexes(){ iR9duP+
return indexes; qonStIP
} @.a59kP8X
!ck~4~J
publicvoid setIndexes(int[] indexes){ >gL&a#<S
this.indexes = indexes; m?yztm~u
} oXht$Q
YI*H]V%w
publicint getStartIndex(){ =s*c(>
return startIndex; (-0d@eqw
} 8r"-3<*
}z/%b<o_
publicvoid setStartIndex(int startIndex){ %7`eT^
if(totalCount <= 0) +RM!j9Rq
this.startIndex = 0; X,G"#j^
elseif(startIndex >= totalCount) ,.2qh|Ol
this.startIndex = indexes X=f %!
ndDF(qHr
[indexes.length - 1]; 0Cf'\2
elseif(startIndex < 0) Q.jThP`p
this.startIndex = 0; $Lbamg->E
else{ C:sgT6
this.startIndex = indexes w{ _g"X
vJi<PQ6
[startIndex / pageSize]; 4noy!h
} ,d lq2
} QX}JQ<8
6A=k;do
publicint getNextIndex(){ 7D>_<)%d=
int nextIndex = getStartIndex() + 98
NFJ
ep},~tPZn
pageSize; ^+d]'$
if(nextIndex >= totalCount) tUOY`]0
return getStartIndex(); `5(F'o
else %ueD3;V
return nextIndex; |Bi7:w
} `ItoL7bi
9a+Y )?z
publicint getPreviousIndex(){ pQc-}o"
int previousIndex = getStartIndex() - uJ0'`Q?6R9
{ Dm@_&
pageSize; nTtEv~a_n
if(previousIndex < 0) ^jRX6
return0; *]R5bj.!o
else WPpO(@sn
return previousIndex; cl4_M{~
} =<PEvIn
@x!+_z
} !"RRw&0M
[lSQMoi3
}!Pty25j
|w#~v%w
抽象业务类 tEo-Mj5:
java代码: :HrFbq
?>V>6cDQ
nnT#S
/** I][&*V1
* Created on 2005-7-12 Np$&8v+en
*/ q7soV(P
package com.javaeye.common.business; H =~7g3
o6~JAvw
import java.io.Serializable; i0+e3!QU
import java.util.List; HIE8@Rv/3
zAklS 7L
import org.hibernate.Criteria; ?D)$OCS
import org.hibernate.HibernateException; *pnaj\
import org.hibernate.Session; eYlI };
import org.hibernate.criterion.DetachedCriteria; zd!%7
UP
import org.hibernate.criterion.Projections; ;&}z
L.!jo
import
!j%
uHmvHA~/c8
org.springframework.orm.hibernate3.HibernateCallback; W|zPV`
import $%31Gk[I
|nLq4.
org.springframework.orm.hibernate3.support.HibernateDaoS ='qVwM['
jpZq]E9`P
upport; |xg#Q`O
4<E <sD
import com.javaeye.common.util.PaginationSupport; -Hw3rv3o
.b<W*4{j0H
public abstract class AbstractManager extends T2azHo7
z6d0Y$A G
HibernateDaoSupport { 4J(-~
P*|=Z>%[0
privateboolean cacheQueries = false; cbm;45 L|
NR8`nc1~
privateString queryCacheRegion; \~Z%}$ =
G'w!Aw s
publicvoid setCacheQueries(boolean Y[R>?w
Z^4+ 88
cacheQueries){ C%]qK(9vvd
this.cacheQueries = cacheQueries; f#GMJ mCQs
} UyV5A
C^B$_?
publicvoid setQueryCacheRegion(String NR
k~
#wRhR>6
queryCacheRegion){ VX8CEO
this.queryCacheRegion = A9K$:mL<2
F?H=2mzKbz
queryCacheRegion; zG 9D
Ph
} h:?qd
m$v >r\*X
publicvoid save(finalObject entity){ i+~BVb
getHibernateTemplate().save(entity); +s8R]3NJ_H
} rrj.]^E_~
2@2d
|
publicvoid persist(finalObject entity){ W
getHibernateTemplate().save(entity); iZeq
l1O
} oxL<\4)WJ
ZOa| lB (,
publicvoid update(finalObject entity){ J!5b~8`v
getHibernateTemplate().update(entity); `G`R|B
} mR
XRuK
l*&N<Yu
publicvoid delete(finalObject entity){ eh]syeKBj
getHibernateTemplate().delete(entity); v3M$UiN,:
} Udn Rsp9S
.o/uA
publicObject load(finalClass entity, $m*Gu:#xm&
=QtFJ9\
finalSerializable id){ kI@<H<
return getHibernateTemplate().load GxG~J4
$rr@3H+
(entity, id); "uIaKb
} @Bhcb.kbq
\({'Xo >(
publicObject get(finalClass entity, t? 6 et1~
+BL4 6Bq
finalSerializable id){ FibZT1-k
return getHibernateTemplate().get {en'8kS
-6NoEmb)\'
(entity, id); &b5(Su
} 5~IdWwG*w
;e5PoLc
publicList findAll(finalClass entity){ _\tv ${
return getHibernateTemplate().find("from -/{FGbpR;
YJ"D"QD
" + entity.getName()); *w*>\ZhOm
} ?-mOAHW0q
'gs P9
publicList findByNamedQuery(finalString s*yl&El/
ws!~MSIy
namedQuery){ O=}Rp1
return getHibernateTemplate z_ycH%p
&*+$38XE^
().findByNamedQuery(namedQuery); /R=MX>JA;
} hd9HM5{p
OmBz'sp:
publicList findByNamedQuery(finalString query, c6 mS
k"&o)*d
finalObject parameter){
Fl=H5HR
return getHibernateTemplate +c<iVc|
-W('^v_*
().findByNamedQuery(query, parameter); w($a'&d`0
}
iD_y@+iz
YFB>GQ;
publicList findByNamedQuery(finalString query, |JYb4J4Ni
Jk\-e`eE
finalObject[] parameters){ j;coP ehB
return getHibernateTemplate {E Ay~lo
r@zT!.sc!
().findByNamedQuery(query, parameters); S5TVfV5LI
} %hYgG;22
U0j>u*yE
publicList find(finalString query){ /CsP@f_Gw
return getHibernateTemplate().find oxc;DfJ_
B1nm?E 0i
(query); L>sLb(2\i
} BM /FOY;
^)>( <6
publicList find(finalString query, finalObject CipDeqau2
[d[w/@
parameter){ W$zRUG-
return getHibernateTemplate().find +8//mrL_/
v~L\[&|_
(query, parameter); iG6]Pr|;e
} nahq O|~
IXa~,a H71
public PaginationSupport findPageByCriteria *GE6zGdN
ekyCZ8iai
(final DetachedCriteria detachedCriteria){ gE\ ^ vaB
return findPageByCriteria d|NW&PG
X13+n2^8]
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0@zJa;z'
} +-|""`I1I
oa"Bpi9i
public PaginationSupport findPageByCriteria 'xqyG XI
J2VPOn
(final DetachedCriteria detachedCriteria, finalint ~+4lmslR
9t\14tVwx
startIndex){ :;eOhZ=_
return findPageByCriteria Cst1nGPL
^vd$j-kjTP
(detachedCriteria, PaginationSupport.PAGESIZE, W$hCI)m(
Ly2,*\7
startIndex); ,nteIR'??
} *b) (-#w3
<p b
public PaginationSupport findPageByCriteria VX.LL
5
.2@T|WD!Ah
(final DetachedCriteria detachedCriteria, finalint ^;PjO|mD
Z
ZNw|5u^N
pageSize, n>.@@
finalint startIndex){ o!UB x<4
return(PaginationSupport) Hu<]*(lK%
lot`6]
getHibernateTemplate().execute(new HibernateCallback(){ ;F@Sz/
publicObject doInHibernate O6y:e#0z
ZiuD0#"!
(Session session)throws HibernateException { L D[\eJ_
Criteria criteria = @3c'4O
tjtvO@?1-
detachedCriteria.getExecutableCriteria(session); q$"u<
int totalCount = |"LHo
H
g]&fyB#
((Integer) criteria.setProjection(Projections.rowCount G]aey>)
zy$jTqDH
()).uniqueResult()).intValue(); 'Jf
LTG.
criteria.setProjection _@B?
Xf&YcHo
(null); xW)
List items = ^oPFLez56
i.6 b%
criteria.setFirstResult(startIndex).setMaxResults M%ecWr!tj
GZaB z#U
(pageSize).list(); ||X3g"2W9
PaginationSupport ps = N@PwC(
h!SsIy(
new PaginationSupport(items, totalCount, pageSize, Y }VJ4!%U
<1I4JPh>x
startIndex); ?=Ceo#Er
return ps; A!!!7tj
} y_L8i[
}, true); b(N\R_IQ~
} QD%xmP
Nxt:U{`T'
public List findAllByCriteria(final ++b[>};
k#pO+[ x
DetachedCriteria detachedCriteria){ 5;KJ0N*-
return(List) getHibernateTemplate DQ+6VPc^o
e4=FO;%
().execute(new HibernateCallback(){ h'em?fN(
publicObject doInHibernate /Yi4j,8!|
FLG"c690
(Session session)throws HibernateException { rGNa[1{kRs
Criteria criteria = fmK~?
h9 DUS,G9,
detachedCriteria.getExecutableCriteria(session); Y910\h@V
return criteria.list(); 0#TL$?=|
} $$ *tK8#
}, true); f$:Y'$Z1
} Zfk]Z9YO
3 orZBT
public int getCountByCriteria(final QBGm)h?=
99*k&mb
DetachedCriteria detachedCriteria){ NUVKAAgMX
Integer count = (Integer) ?`e@ o?
mhrF9&s
getHibernateTemplate().execute(new HibernateCallback(){ _ab8z]H
publicObject doInHibernate AR( gI]1
U%bm{oVn
(Session session)throws HibernateException { P9
HKev?y
Criteria criteria = cdkEK
o} QP+
detachedCriteria.getExecutableCriteria(session); V/H+9+B7Im
return XgX~K:<jt
Ojz'p5d`>
criteria.setProjection(Projections.rowCount c6 &k?Puy
xz0t8`NoN
()).uniqueResult(); b||usv[or
} c!
kr
BS
}, true); ynM:]*~K
return count.intValue(); I1m[M?
} W8bp3JX"
} Pa0W|q#?X
!0hyp |F:>
mW!n%f
y'`7zJ
>vo 6X]p~
'cc8xC
用户在web层构造查询条件detachedCriteria,和可选的 }Fu1Y@M%
zZPWE"u}
startIndex,调用业务bean的相应findByCriteria方法,返回一个 PcA^ jBgGl
A z@@0
PaginationSupport的实例ps。 # *pB"L
vdn)+fZ;
ps.getItems()得到已分页好的结果集 n\D/WLv M
ps.getIndexes()得到分页索引的数组 sXEIC#rq
ps.getTotalCount()得到总结果数 0cKsGDm
ps.getStartIndex()当前分页索引 )t+pwh!8
ps.getNextIndex()下一页索引 Uf+y$n-
ps.getPreviousIndex()上一页索引 mK$E&,OkA
#!z-)[S.+
zqt<[=O
$+J39%Y!^
lz>00B<Z
d+)L K~
U/{t" e
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 IY6Ll6OK
!VIxEu^ke
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Zs/-/C|
Dti-*LB1
一下代码重构了。 %8I^&~E1
'fK=;mM
我把原本我的做法也提供出来供大家讨论吧: -w2^26ax
A4(L47^
首先,为了实现分页查询,我封装了一个Page类: M:OZWYQ
java代码: 16eP7s
p'^}J$
_YR#J%xa
/*Created on 2005-4-14*/ U%r{{Q1
package org.flyware.util.page; !-T#dU
HLz<C
/** pW8?EGO@
* @author Joa @=w)a
* >.P*lT
*/ =.S2gO >
publicclass Page { W:n\,P
YhglL!pC
/** imply if the page has previous page */ "?k'S{;
privateboolean hasPrePage; PT,*KYF_O"
_Q^jk0K8ga
/** imply if the page has next page */ 8bMw.u=F
privateboolean hasNextPage; "Vc|D (g
?~.9:93
/** the number of every page */ X)]>E]X
privateint everyPage; B> i^ w1
o(v`
/** the total page number */ 1G`5FU
privateint totalPage; nUONI+6Z/
.Sw4{m[g
/** the number of current page */ ;w%g*S
privateint currentPage; `,pBOh|'
}T902RL0
/** the begin index of the records by the current jyg>'"W
E.$//P n|1
query */ 056yhB
privateint beginIndex; AS0(NlV
8_>:0(y
~:!&