Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 YAvOV-L
QmpP_eS >
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 dO{a!Ca
quPNwNy
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 _Bp{~-fO
Qg\{d)X[N
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 SQ_w~'(
Bi'qy]%
。 uGxh}'&
gh{Z=_
分页支持类: M'
d ,TV[
Hmi]qK[F
java代码: NQx`u"=
?!4xtOA
V#Hg+\{d
package com.javaeye.common.util; d 18>0R
ph;ds+b
import java.util.List; b;X|[tB
)S;pYVVAl
publicclass PaginationSupport { l".LtUf-
2!u4nxZ.
publicfinalstaticint PAGESIZE = 30; wInJ!1
,a&&y0,
privateint pageSize = PAGESIZE; /kLG/ry8l:
PSM~10l,
privateList items; CSC
sJE#4
*}hx9:9\B
privateint totalCount; srbU}u3VZ
iIe\m V
privateint[] indexes = newint[0]; 1+f>tv
+NH#t}.
privateint startIndex = 0; tS2Orzc>,
;ORT#7CU
public PaginationSupport(List items, int q
(?%$u.
0KQDw
totalCount){ 8hK\Ya:mP
setPageSize(PAGESIZE); e95x,|.-_
setTotalCount(totalCount); ># {,(8\
setItems(items); &ZmHR^Flz
setStartIndex(0); V@QWJZ"
} _.ny<r:g
xzqgem`[\
public PaginationSupport(List items, int \,b@^W6e>
X~`<ik{q
totalCount, int startIndex){ *Z+8L*k97
setPageSize(PAGESIZE); jI-\~
setTotalCount(totalCount); ]Ywj@-*q
setItems(items); `H_.<``>
setStartIndex(startIndex); P2q'P&
} `pHlGbrW
nMniHB'
public PaginationSupport(List items, int km)5?
&rcC7v K9
totalCount, int pageSize, int startIndex){ /ynvQ1#uA
setPageSize(pageSize); HR/"Nwr
setTotalCount(totalCount); "o=*f/M
setItems(items); A1mxM5N
setStartIndex(startIndex); : " ([i"
} Vz"Ja
K,VN?t<h
publicList getItems(){ ww_gG5Fc$
return items; w4S0aR:yL
} AS}
FRNIVx
UJqDZIvC
publicvoid setItems(List items){ vbDSNm#Yv
this.items = items; 8op,;Z7Y
} ugZ-*e7
HW{si]~q
publicint getPageSize(){ {Q&@vbw'
return pageSize; zjzW;bo( d
} Y55Yo5<j/+
>O{[w'sWa
publicvoid setPageSize(int pageSize){ 7lo`)3mB
this.pageSize = pageSize; k3-'!dW<
} \Kx@?,
PWwz<AI+
publicint getTotalCount(){ ]w3-No
return totalCount; 5eZ8$-&([
} DP(JsZ}
!L+4YA
publicvoid setTotalCount(int totalCount){ #hA]r.
if(totalCount > 0){
AE_7sM
this.totalCount = totalCount; [r,ZM
int count = totalCount / wTpjM@F?J|
* 5H
pageSize; 7+,6m!4
if(totalCount % pageSize > 0) [>B`"nyNQ
count++; DE{tpN
indexes = newint[count]; Kc6p||<
for(int i = 0; i < count; i++){ 2WP73:'t
indexes = pageSize * i.|zKjF'
'^TQ Ubw
i; y?ps+ce93
} OZ/P@`kN.f
}else{ Pl@3=s!~>~
this.totalCount = 0; :GXD-6}^|
} (BB&ZUdyv
} KxEy
N (n
S(K}.C1x
publicint[] getIndexes(){ DNP%]{J
return indexes; |C \%H R
} zyznFiE
v4?qI >/
publicvoid setIndexes(int[] indexes){ "kLu]M<
this.indexes = indexes; '|zkRdB*Lq
} MOiTzL*
Ur`jmB
publicint getStartIndex(){ yFIB/ln:
return startIndex; ?,_$;g
} VSK!Pc.G}
v<*ga7'S
publicvoid setStartIndex(int startIndex){ 1eg/<4]hA
if(totalCount <= 0) CXb-{|I}d
this.startIndex = 0; 7*!h:rg
elseif(startIndex >= totalCount) xq?9w$
this.startIndex = indexes _I("k:E7
]BY^.!Y
[indexes.length - 1]; H nKO
elseif(startIndex < 0) ` ^rN"\
this.startIndex = 0; X1A~#w>
else{ X+'z@xpj
this.startIndex = indexes NTnjVU
}
=@98Gl9!
[startIndex / pageSize]; Js`xTH'
} .L,xqd[zC
} N36<EHq
S,K'y?6
publicint getNextIndex(){ @Axwj
int nextIndex = getStartIndex() + I:6N?lD4}0
&"D *
pageSize; jTo-xP{lC
if(nextIndex >= totalCount) P1<Y7+n
return getStartIndex(); DNARe!pK
else Kt(Z&@
return nextIndex; :UjF<V
} 8"d0Su4r
C~16Jj:v
publicint getPreviousIndex(){ ]Iku(<*Ya
int previousIndex = getStartIndex() - 9#:b+Amzz
!xU1[,9
pageSize; ;TaR1e0
if(previousIndex < 0) N;<.::x
return0; d?j_L`?+
else \DP*?D_}?
return previousIndex; )c'5M]V
} Ca: jN0
x%acWeV5
} *Q?ZJS~
V3<baxdE
fl{wF@C6
ogcEv>0
抽象业务类 !"*!du28jo
java代码: =")}wl=s
]K]$FX<f
7Z-'@m
/** ?o@5PL
* Created on 2005-7-12
E *[dc
*/ ;Up'+[Vj'C
package com.javaeye.common.business; ~m
,xG
ZI'MfkEZ*
import java.io.Serializable; A]fN~PR
import java.util.List; 7j9:s>D
l8I`%bu
import org.hibernate.Criteria; gW{<:6}!*
import org.hibernate.HibernateException; 'cs!(z-{x
import org.hibernate.Session; ^DL}J>F9G
import org.hibernate.criterion.DetachedCriteria; ^4Nk13
import org.hibernate.criterion.Projections; UL81x72O
import JArSJ:}
Dg^n`[WO
org.springframework.orm.hibernate3.HibernateCallback; #~A (%a
import KeU|E<|!
QvM+]pdR6
org.springframework.orm.hibernate3.support.HibernateDaoS k z|2PP
8p4J7 -
upport; p0 @,-
`[hc{ynO|
import com.javaeye.common.util.PaginationSupport; Nm{\?
. ZuRH_pI
public abstract class AbstractManager extends r(ej=aR
Ls8@@b,t2
HibernateDaoSupport { )ZxDfRjL
"O{_LOJ
privateboolean cacheQueries = false; nz72w_
hE|Z~5\Y,>
privateString queryCacheRegion; =x9SvIm/tH
{H]xA 3[]
publicvoid setCacheQueries(boolean p2]@yE7w
t')47k\
cacheQueries){ AJk0jh\.j%
this.cacheQueries = cacheQueries; XLEEd?Vct9
} )tH.P:
1~,
J~=bW\^I
publicvoid setQueryCacheRegion(String l@ +lUx8
%4F
Q~
queryCacheRegion){ 4CO"> :
this.queryCacheRegion = hu?Q,[+o
z >EO Qe
queryCacheRegion; tDWW
4H
} +D[|Mi
~vqVASUc,
publicvoid save(finalObject entity){ |Ai/q6u
getHibernateTemplate().save(entity); X9W'.s.[Q
} gZa/?[+
]Gk;n/!
B
publicvoid persist(finalObject entity){ \!!qzrq
getHibernateTemplate().save(entity); QucDIZ
} |Z]KF>S]
L-B"P&
publicvoid update(finalObject entity){ xvP=i/SO
getHibernateTemplate().update(entity);
]/l"
} Q5[x2 s_ d
:O`7kZ]=n
publicvoid delete(finalObject entity){ ~d0:>8zQR
getHibernateTemplate().delete(entity); 4*k>M+o/C4
}
;E Z5/"T
N$\'X<{
publicObject load(finalClass entity, p~Tp=d)/
=NHE_4/p
finalSerializable id){ rF9|xgFK
return getHibernateTemplate().load [}xVz"8 V
6`KR
(entity, id); ,2t|(V*"&
} Ban@$uf
yyp0GV.x
publicObject get(finalClass entity, [v@3|@
SM57bN
finalSerializable id){ }ufzlHD
return getHibernateTemplate().get 8Zj=:;
N>R\,n|I
(entity, id); 3.i$lp`t
} 5yOIwzr&Uu
eAU0 8gM.
publicList findAll(finalClass entity){
fQW1&lFT
return getHibernateTemplate().find("from se|>P=/
U2v;[ >=]
" + entity.getName()); [HRry2#s
} $|kq{@<
^Rr!YnEN
publicList findByNamedQuery(finalString ?c G~M|@
zKh^BwhO|X
namedQuery){ i-.]onR
return getHibernateTemplate myq@X(K
s$%t*T2J>
().findByNamedQuery(namedQuery); R07]{
} cTC -cgp
sj9j47y
publicList findByNamedQuery(finalString query, FEC`dSTI
^T?zR7r
finalObject parameter){ csh@C
ckC8
return getHibernateTemplate lN(|EI
z3n273W>6
().findByNamedQuery(query, parameter); hgYi ,e
} 0V RV.Ml
a&^HvXO(>(
publicList findByNamedQuery(finalString query, ro& /
a+HGlj 2>
finalObject[] parameters){ EZ,Tc;f=
return getHibernateTemplate 'CQ~ZV5
yL2sce[
().findByNamedQuery(query, parameters); {GH0>
1&
} '99rXw
C F,-l
B
publicList find(finalString query){ #mIgk'kW<
return getHibernateTemplate().find "[wkjNf%
5T*Uq>x0
(query); Arr(rM
} 8"'Z0
Ey
xK*G'3Ge
publicList find(finalString query, finalObject {PGiNY%q
Y)O88C
parameter){
ff;9P5X
return getHibernateTemplate().find v pg*J/1[
dguN<yS-E
(query, parameter); ?&`PN<~2z
} Ad}Nc"O
]| xfKDu
public PaginationSupport findPageByCriteria N9dx^+\
`{oFdvL~)
(final DetachedCriteria detachedCriteria){ 5cUz^ >
return findPageByCriteria &Z3u(Eb
=x
xN3Ay
(detachedCriteria, PaginationSupport.PAGESIZE, 0); MdC}!&W
} ;aj4V<@
.OM^@V~T
public PaginationSupport findPageByCriteria op2<~v0?
3(oB[9]s
(final DetachedCriteria detachedCriteria, finalint J16t&Ha`
@<TC+M5!
startIndex){ QmKEl|/{u
return findPageByCriteria nk*T
x
Al
MMN"j
(detachedCriteria, PaginationSupport.PAGESIZE, _:1s7EC
tLE7s_^
startIndex); g`Kh&|GU
} 1 u~Xk?
0Yk$f1g
public PaginationSupport findPageByCriteria yC:C
qNuBK6E#4
(final DetachedCriteria detachedCriteria, finalint I.6
qA *
I&J>
pageSize, V;LV),R?
finalint startIndex){ b Y2:g )
return(PaginationSupport) ,k9xI<i
O>@ChQF
getHibernateTemplate().execute(new HibernateCallback(){
O`^dy7>{U
publicObject doInHibernate vNDf1B5z
D_Zt:tzO
(Session session)throws HibernateException { ,%T
sfB
Criteria criteria = 4[lym,8C
Xk(p:^ R
detachedCriteria.getExecutableCriteria(session); YlC$L$%Zd.
int totalCount = :^En\YcU
X()yhe_
((Integer) criteria.setProjection(Projections.rowCount K^Ho%_)
PJ))p6
9
()).uniqueResult()).intValue(); xFScj0Y
criteria.setProjection
|W\U9n
v.6K;TY.
(null); 3Viz0I<%
List items = rqWD#FB=z
e9;5.m
criteria.setFirstResult(startIndex).setMaxResults >c@jl
Tr.u'b(
(pageSize).list(); mhgvN-? "h
PaginationSupport ps = M,vCAZ
ZK4d;oa",
new PaginationSupport(items, totalCount, pageSize, 7PbwCRg
o_sb+Vn|
startIndex); 3rj7]:Vr
return ps; 7Tc^}Q
} cz41<SFL
}, true); MMy\u) 4
} -KL5sK
-PCFOm"
public List findAllByCriteria(final #G]g
O%1uBc
DetachedCriteria detachedCriteria){ T(=Z0M
return(List) getHibernateTemplate V`4/oM`
Gm[XnUR7V
().execute(new HibernateCallback(){ C/!7E:
publicObject doInHibernate 'j\~> a3\
bo-lT-I
(Session session)throws HibernateException { |Sv}/P-
Criteria criteria = `hDH7u!U.
#2dH2k\F
detachedCriteria.getExecutableCriteria(session); .k"unclT0
return criteria.list(); ,: Ij@u>)
} 6Zx)L|B
}, true); 97pfMk1_
} Oh3A?!y#
!8I80:e_~
public int getCountByCriteria(final !>?*gc.<
";Q}Gs}
DetachedCriteria detachedCriteria){ C.RXQ`-P}
Integer count = (Integer) !}hG|Y6s
' 7H"ezt
getHibernateTemplate().execute(new HibernateCallback(){ 0"l`M5-KP
publicObject doInHibernate ,0@QBr5P
6f^IAa|
(Session session)throws HibernateException { hO2W!68
Criteria criteria = BU O8Z]
7;a
detachedCriteria.getExecutableCriteria(session); Ae*
6&R4
return {Fvl7Sh
!l$k6,WJi
criteria.setProjection(Projections.rowCount <C_FRpR<f
q4SEvP}fLx
()).uniqueResult(); LaYd7Oyf]
} p^s:s-"f\
}, true); ZKJhmk
return count.intValue(); l\37/Z
} MxqIB(5k
} y9~:[ jB
~Kt2g\BSok
9vBW CCf
,7)zavA
{$I1(DYN
L=gG23U&
用户在web层构造查询条件detachedCriteria,和可选的 @CS%=tE}U
#kgLdd"
startIndex,调用业务bean的相应findByCriteria方法,返回一个 0lU
pil
s)#TT9BbV
PaginationSupport的实例ps。 U
U3o (Yq
L0qL\>#ejr
ps.getItems()得到已分页好的结果集 xHe"c<
ps.getIndexes()得到分页索引的数组 C8O<fwNM
ps.getTotalCount()得到总结果数 T~
P<Gq},
ps.getStartIndex()当前分页索引 IM_SZs
ps.getNextIndex()下一页索引 }J6 y NoXu
ps.getPreviousIndex()上一页索引 $mxl&Qr>Q;
$ncP#6
XrJLlH>R4
s=Xg6 D
PY#_$ C
>]x%+@{|
s8;*Wt
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A$rCo~Ek
]f6,4[
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 1]"S?
A#gy[.Bb
一下代码重构了。 eC@b-q
xmejoOF
我把原本我的做法也提供出来供大家讨论吧: CUx-k|\
GQYB2{e>
首先,为了实现分页查询,我封装了一个Page类: 1-.(pA'
java代码: 4veXg/l
C_&ZQlgQ
2BO"mc<#$
/*Created on 2005-4-14*/ 7
b{y
package org.flyware.util.page; XdE|7=+s
s0'6r$xj
/** SP4(yJy&
* @author Joa P&Wf.qr{:
* J
IE0O`
*/ X$=/H 6R5Z
publicclass Page { ]+Z,HY@;-
>6|Xvtf
/** imply if the page has previous page */ %?J-0
privateboolean hasPrePage; ZQyX zERp
zor
/** imply if the page has next page */ 6%MM)Vj+u
privateboolean hasNextPage; 5k;}I|rg %
NYeL1h)l
/** the number of every page */ dvLL~VP
privateint everyPage; =00sB
_Nf%x1m5s
/** the total page number */ =(Y+u
privateint totalPage; [f?x,W~
0y%s\,PsT
/** the number of current page */ 2>)::9e4
privateint currentPage; P}vk5o'
Ki(0s
/** the begin index of the records by the current {( Ba
e!w#{</8Q
query */ i<!1s%i}
privateint beginIndex; >fp_$bjd
VqS1n
VP^{-mDph
/** The default constructor */ o97*3W]
public Page(){ &H%z1Lp
)Ut9k
} .#LHj}u
>[<f\BN|
/** construct the page by everyPage o`nJJ:Cxq-
* @param everyPage ]3
76F7
* */ X]s="^
public Page(int everyPage){ -ug-rdXV
this.everyPage = everyPage; D 1(9/;9
} HFX,EE
_+<AxE9\
/** The whole constructor */ G#3$sz
public Page(boolean hasPrePage, boolean hasNextPage, ~I@ %ysR
~sTn?~
ootkf=
int everyPage, int totalPage, 1$ENNq#0
int currentPage, int beginIndex){ -Zqw[2Q4
this.hasPrePage = hasPrePage; c@$W]o"A
this.hasNextPage = hasNextPage; L"}2Y3
this.everyPage = everyPage; \cQ+9e)
this.totalPage = totalPage; bLO^5` 6
this.currentPage = currentPage; -pQ0,/}K
this.beginIndex = beginIndex; uCj)7>}v{M
} 2,p= %
IeB^BD+j
/** V5+|H1=
* @return 9L>ep&u)^
* Returns the beginIndex. uExYgI`<%&
*/ `rpmh7*WV
publicint getBeginIndex(){ a lyA#zao|
return beginIndex; &&Otj-n5
} ki8Jl}dr
/p)y!5e
/** W\O.[7JP
* @param beginIndex "Jg*
/F
* The beginIndex to set. uC?/p1
*/ j^ttTq|l
publicvoid setBeginIndex(int beginIndex){ hn e}G._b
this.beginIndex = beginIndex; JR|P]}
} LGWQBEXw
T/q*k)IoR
/** &_3o 1<
* @return Bb7Vf7>
* Returns the currentPage. gh%Q9Ni-
*/ T8Ye+eP}
publicint getCurrentPage(){ q]v{o8:U
return currentPage; 2 '8I/>-
} Sv[+~co<l
Obc wmL
/** 2K2_-
* @param currentPage B";Dj~y
* The currentPage to set. qcfg 55]'c
*/ jNAboSf2Y
publicvoid setCurrentPage(int currentPage){ r:,"k:C
this.currentPage = currentPage; FwDEYG
} .FvIT]k-
IDp2#qg_
/** hlHle\[ds
* @return o6 8;-b'n
* Returns the everyPage. nu6v@<<F>
*/ [-1Yyy1}
publicint getEveryPage(){ ]F4|@+\9
return everyPage; Y~UWUF%aK
} nW ]T-!
?d)FYB
/** RY~mQ
* @param everyPage a'7RzN ,]
* The everyPage to set. rM20Y(|
*/ }5y]kn
publicvoid setEveryPage(int everyPage){ =l%|W[OO
this.everyPage = everyPage; D/tFN+|P
} r,ep{
p
BsYJIKfW
/** s+a#x(7{
* @return tS[@?qP
* Returns the hasNextPage. 1pTQMf a
*/ J!iKW
publicboolean getHasNextPage(){
bRx}ih
return hasNextPage; }SGb`l
} CMYkxU
`W %R
/** B{NGrC`5)
* @param hasNextPage 78E<_UgcB
* The hasNextPage to set. }Q_ }c9?
*/ ;uqi
publicvoid setHasNextPage(boolean hasNextPage){ - S%8
this.hasNextPage = hasNextPage; {?]&